From 93f69ff9a0c9b05dfbbdcf6f7d737a68fc4d3bd1 Mon Sep 17 00:00:00 2001 From: tobigun Date: Sun, 6 Apr 2008 12:18:01 +0000 Subject: - removed (linux incompatible) PngImage. In addition it was rather outdated (from 2003, newest version is from 2006) - introduced UImage-unit for JPG/PNG/BMP image saving - the png part uses the libpng12-0.dll (part of SDL_Image) so - the jpg part uses either Delphi's Jpeg unit or FPC's base/pasjpeg unit -> so no additional libs are needed. git-svn-id: svn://svn.code.sf.net/p/ultrastardx/svn/trunk@1007 b956fd51-792f-4845-bead-9b4dfca2ff2c --- Game/Code/lib/PngImage/pngimage.~pas | 5205 ---------------------------------- 1 file changed, 5205 deletions(-) delete mode 100644 Game/Code/lib/PngImage/pngimage.~pas (limited to 'Game/Code/lib/PngImage/pngimage.~pas') diff --git a/Game/Code/lib/PngImage/pngimage.~pas b/Game/Code/lib/PngImage/pngimage.~pas deleted file mode 100644 index ec712737..00000000 --- a/Game/Code/lib/PngImage/pngimage.~pas +++ /dev/null @@ -1,5205 +0,0 @@ -{Portable Network Graphics Delphi 1.4361 (8 March 2003) } - -{This is the latest implementation for TPngImage component } -{It's meant to be a full replacement for the previous one. } -{There are lots of new improvements, including cleaner code, } -{full partial transparency support, speed improvements, } -{saving using ADAM 7 interlacing, better error handling, also } -{the best compression for the final image ever. And now it's } -{truly able to read about any png image. } - -{ - Version 1.4361 - 2003-03-04 - Fixed important bug for simple transparency when using - RGB, Grayscale color modes - - Version 1.436 - 2003-03-04 - * NEW * Property Pixels for direct access to pixels - * IMPROVED * Palette property (TPngObject) (read only) - Slovenian traslation for the component (Miha Petelin) - Help file update (scanline article/png->jpg example) - - Version 1.435 - 2003-11-03 - * NEW * New chunk implementation zTXt (method AddzTXt) - * NEW * New compiler flags to store the extra 8 bits - from 16 bits samples (when saving it is ignored), the - extra data may be acessed using ExtraScanline property - * Fixed * a bug on tIMe chunk - French translation included (Thanks to IBE Software) - Bugs fixed - - Version 1.432 - 2002-08-24 - * NEW * A new method, CreateAlpha will transform the - current image into partial transparency. - Help file updated with a new article on how to handle - partial transparency. - - Version 1.431 - 2002-08-14 - Fixed and tested to work on: - C++ Builder 3 - C++ Builder 5 - Delphi 3 - There was an error when setting TransparentColor, fixed - New method, RemoveTransparency to remove image - BIT TRANSPARENCY - - Version 1.43 - 2002-08-01 - * NEW * Support for Delphi 3 and C++ Builder 3 - Implements mostly some things that were missing, - a few tweaks and fixes. - - Version 1.428 - 2002-07-24 - More minor fixes (thanks to Ian Boyd) - Bit transparency fixes - * NEW * Finally support to bit transparency - (palette / rgb / grayscale -> all) - - Version 1.427 - 2002-07-19 - Lots of bugs and leaks fixed - * NEW * method to easy adding text comments, AddtEXt - * NEW * property for setting bit transparency, - TransparentColor - - Version 1.426 - 2002-07-18 - Clipboard finally fixed (hope) - Changed UseDelphi trigger to UseDelphi - * NEW * Support for bit transparency bitmaps - when assigning from/to TBitmap objects - Altough it does not support drawing transparent - parts of bit transparency pngs (only partial) - it is closer than ever - - Version 1.425 - 2002-07-01 - Clipboard methods implemented - Lots of bugs fixed - - Version 1.424 - 2002-05-16 - Scanline and AlphaScanline are now working correctly. - New methods for handling the clipboard - - Version 1.423 - 2002-05-16 - * NEW * Partial transparency for 1, 2, 4 and 8 bits is - also supported using the tRNS chunk (for palette and - grayscaling). - New bug fixes (Peter Haas). - - Version 1.422 - 2002-05-14 - Fixed some critical leaks, thanks to Peter Haas tips. - New translation for German (Peter Haas). - - Version 1.421 - 2002-05-06 - Now uses new ZLIB version, 1.1.4 with some security - fixes. - LoadFromResourceID and LoadFromResourceName added and - help file updated for that. - The resources strings are now located in pnglang.pas. - New translation for Brazilian Portuguese. - Bugs fixed. - - IMPORTANT: I'm currently looking for bugs on the library. If - anyone has found one, please send me an email and - I will fix right away. Thanks for all the help and - ideias I'm receiving so far.} - -{My new email is: gubadaud@terra.com.br} -{Website link : pngdelphi.sourceforge.net} -{Gustavo Huffenbacher Daud} - -unit pngimage; - -interface - -{Triggers avaliable (edit the fields bellow)} -{$DEFINE UseDelphi} //Disable fat vcl units (perfect to small apps) -{$DEFINE ErrorOnUnknownCritical} //Error when finds an unknown critical chunk -{$DEFINE CheckCRC} //Enables CRC checking -{$DEFINE RegisterGraphic} //Registers TPNGObject to use with TPicture -{$DEFINE PartialTransparentDraw} //Draws partial transparent images -{.$DEFINE Store16bits} //Stores the extra 8 bits from 16bits/sample -{.$DEFINE Debug} //For programming purposes -{$RANGECHECKS OFF} {$J+} - - - -uses - Windows {$IFDEF UseDelphi}, Classes, Graphics, SysUtils{$ENDIF} {$IFDEF Debug}, - dialogs{$ENDIF}, pngzlib, pnglang; - -{$IFNDEF UseDelphi} - const - soFromBeginning = 0; - soFromCurrent = 1; - soFromEnd = 2; -{$ENDIF} - -const - {ZLIB constants} - ZLIBErrors: Array[-6..2] of string = ('incompatible version (-6)', - 'buffer error (-5)', 'insufficient memory (-4)', 'data error (-3)', - 'stream error (-2)', 'file error (-1)', '(0)', 'stream end (1)', - 'need dictionary (2)'); - Z_NO_FLUSH = 0; - Z_FINISH = 4; - Z_STREAM_END = 1; - - {Avaliable PNG filters for mode 0} - FILTER_NONE = 0; - FILTER_SUB = 1; - FILTER_UP = 2; - FILTER_AVERAGE = 3; - FILTER_PAETH = 4; - - {Avaliable color modes for PNG} - COLOR_GRAYSCALE = 0; - COLOR_RGB = 2; - COLOR_PALETTE = 3; - COLOR_GRAYSCALEALPHA = 4; - COLOR_RGBALPHA = 6; - - -type - {$IFNDEF UseDelphi} - {Custom exception handler} - Exception = class(TObject) - constructor Create(Msg: String); - end; - ExceptClass = class of Exception; - TColor = ColorRef; - {$ENDIF} - - {Error types} - EPNGOutMemory = class(Exception); - EPngError = class(Exception); - EPngUnexpectedEnd = class(Exception); - EPngInvalidCRC = class(Exception); - EPngInvalidIHDR = class(Exception); - EPNGMissingMultipleIDAT = class(Exception); - EPNGZLIBError = class(Exception); - EPNGInvalidPalette = class(Exception); - EPNGInvalidFileHeader = class(Exception); - EPNGIHDRNotFirst = class(Exception); - EPNGNotExists = class(Exception); - EPNGSizeExceeds = class(Exception); - EPNGMissingPalette = class(Exception); - EPNGUnknownCriticalChunk = class(Exception); - EPNGUnknownCompression = class(Exception); - EPNGUnknownInterlace = class(Exception); - EPNGNoImageData = class(Exception); - EPNGCouldNotLoadResource = class(Exception); - EPNGCannotChangeTransparent = class(Exception); - EPNGHeaderNotPresent = class(Exception); - -type - {Direct access to pixels using R,G,B} - TRGBLine = array[word] of TRGBTriple; - pRGBLine = ^TRGBLine; - - {Same as TBitmapInfo but with allocated space for} - {palette entries} - TMAXBITMAPINFO = packed record - bmiHeader: TBitmapInfoHeader; - bmiColors: packed array[0..255] of TRGBQuad; - end; - - {Transparency mode for pngs} - TPNGTransparencyMode = (ptmNone, ptmBit, ptmPartial); - {Pointer to a cardinal type} - pCardinal = ^Cardinal; - {Access to a rgb pixel} - pRGBPixel = ^TRGBPixel; - TRGBPixel = packed record - B, G, R: Byte; - end; - - {Pointer to an array of bytes type} - TByteArray = Array[Word] of Byte; - pByteArray = ^TByteArray; - - {Forward} - TPNGObject = class; - pPointerArray = ^TPointerArray; - TPointerArray = Array[Word] of Pointer; - - {Contains a list of objects} - TPNGPointerList = class - private - fOwner: TPNGObject; - fCount : Cardinal; - fMemory: pPointerArray; - function GetItem(Index: Cardinal): Pointer; - procedure SetItem(Index: Cardinal; const Value: Pointer); - protected - {Removes an item} - function Remove(Value: Pointer): Pointer; virtual; - {Inserts an item} - procedure Insert(Value: Pointer; Position: Cardinal); - {Add a new item} - procedure Add(Value: Pointer); - {Returns an item} - property Item[Index: Cardinal]: Pointer read GetItem write SetItem; - {Set the size of the list} - procedure SetSize(const Size: Cardinal); - {Returns owner} - property Owner: TPNGObject read fOwner; - public - {Returns number of items} - property Count: Cardinal read fCount write SetSize; - {Object being either created or destroyed} - constructor Create(AOwner: TPNGObject); - destructor Destroy; override; - end; - - {Forward declaration} - TChunk = class; - TChunkClass = class of TChunk; - - {Same as TPNGPointerList but providing typecasted values} - TPNGList = class(TPNGPointerList) - private - {Used with property Item} - function GetItem(Index: Cardinal): TChunk; - public - {Removes an item} - procedure RemoveChunk(Chunk: TChunk); overload; - {Add a new chunk using the class from the parameter} - function Add(ChunkClass: TChunkClass): TChunk; - {Returns pointer to the first chunk of class} - function ItemFromClass(ChunkClass: TChunkClass): TChunk; - {Returns a chunk item from the list} - property Item[Index: Cardinal]: TChunk read GetItem; - end; - - {$IFNDEF UseDelphi} - {The STREAMs bellow are only needed in case delphi provided ones is not} - {avaliable (UseDelphi trigger not set)} - {Object becomes handles} - TCanvas = THandle; - TBitmap = HBitmap; - {Trick to work} - TPersistent = TObject; - - {Base class for all streams} - TStream = class - protected - {Returning/setting size} - function GetSize: Longint; virtual; - procedure SetSize(const Value: Longint); virtual; abstract; - {Returns/set position} - function GetPosition: Longint; virtual; - procedure SetPosition(const Value: Longint); virtual; - public - {Returns/sets current position} - property Position: Longint read GetPosition write SetPosition; - {Property returns/sets size} - property Size: Longint read GetSize write SetSize; - {Allows reading/writing data} - function Read(var Buffer; Count: Longint): Cardinal; virtual; abstract; - function Write(const Buffer; Count: Longint): Cardinal; virtual; abstract; - {Copies from another Stream} - function CopyFrom(Source: TStream; - Count: Cardinal): Cardinal; virtual; - {Seeks a stream position} - function Seek(Offset: Longint; Origin: Word): Longint; virtual; abstract; - end; - - {File stream modes} - TFileStreamMode = (fsmRead, fsmWrite, fsmCreate); - TFileStreamModeSet = set of TFileStreamMode; - - {File stream for reading from files} - TFileStream = class(TStream) - private - {Opened mode} - Filemode: TFileStreamModeSet; - {Handle} - fHandle: THandle; - protected - {Set the size of the file} - procedure SetSize(const Value: Longint); override; - public - {Seeks a file position} - function Seek(Offset: Longint; Origin: Word): Longint; override; - {Reads/writes data from/to the file} - function Read(var Buffer; Count: Longint): Cardinal; override; - function Write(const Buffer; Count: Longint): Cardinal; override; - {Stream being created and destroy} - constructor Create(Filename: String; Mode: TFileStreamModeSet); - destructor Destroy; override; - end; - - {Stream for reading from resources} - TResourceStream = class(TStream) - constructor Create(Instance: HInst; const ResName: String; ResType:PChar); - private - {Variables for reading} - Size: Integer; - Memory: Pointer; - Position: Integer; - protected - {Set the size of the file} - procedure SetSize(const Value: Longint); override; - public - {Stream processing} - function Read(var Buffer; Count: Integer): Cardinal; override; - function Seek(Offset: Integer; Origin: Word): Longint; override; - function Write(const Buffer; Count: Longint): Cardinal; override; - end; - {$ENDIF} - - {Forward} - TChunkIHDR = class; - {Interlace method} - TInterlaceMethod = (imNone, imAdam7); - {Compression level type} - TCompressionLevel = 0..9; - {Filters type} - TFilter = (pfNone, pfSub, pfUp, pfAverage, pfPaeth); - TFilters = set of TFilter; - - {Png implementation object} - TPngObject = class{$IFDEF UseDelphi}(TGraphic){$ENDIF} - protected - {Gamma table values} - GammaTable, InverseGamma: Array[Byte] of Byte; - procedure InitializeGamma; - private - {Temporary palette} - TempPalette: HPalette; - {Filters to test to encode} - fFilters: TFilters; - {Compression level for ZLIB} - fCompressionLevel: TCompressionLevel; - {Maximum size for IDAT chunks} - fMaxIdatSize: Cardinal; - {Returns if image is interlaced} - fInterlaceMethod: TInterlaceMethod; - {Chunks object} - fChunkList: TPngList; - {Clear all chunks in the list} - procedure ClearChunks; - {Returns if header is present} - function HeaderPresent: Boolean; - {Returns linesize and byte offset for pixels} - procedure GetPixelInfo(var LineSize, Offset: Cardinal); - procedure SetMaxIdatSize(const Value: Cardinal); - function GetAlphaScanline(const LineIndex: Integer): pByteArray; - function GetScanline(const LineIndex: Integer): Pointer; - {$IFDEF Store16bits} - function GetExtraScanline(const LineIndex: Integer): Pointer; - {$ENDIF} - function GetTransparencyMode: TPNGTransparencyMode; - function GetTransparentColor: TColor; - procedure SetTransparentColor(const Value: TColor); - protected - {Returns the image palette} - function GetPalette: HPALETTE; {$IFDEF UseDelphi}override;{$ENDIF} - {Returns/sets image width and height} - function GetWidth: Integer; {$IFDEF UseDelphi}override;{$ENDIF} - function GetHeight: Integer; {$IFDEF UseDelphi}override; {$ENDIF} - procedure SetWidth(Value: Integer); {$IFDEF UseDelphi}override; {$ENDIF} - procedure SetHeight(Value: Integer); {$IFDEF UseDelphi}override;{$ENDIF} - {Assigns from another TPNGObject} - procedure AssignPNG(Source: TPNGObject); - {Returns if the image is empty} - function GetEmpty: Boolean; {$IFDEF UseDelphi}override; {$ENDIF} - {Used with property Header} - function GetHeader: TChunkIHDR; - {Draws using partial transparency} - procedure DrawPartialTrans(DC: HDC; Rect: TRect); - {$IFDEF UseDelphi} - {Returns if the image is transparent} - function GetTransparent: Boolean; override; - {$ENDIF} - {Returns a pixel} - function GetPixels(const X, Y: Integer): TColor; virtual; - procedure SetPixels(const X, Y: Integer; const Value: TColor); virtual; - public - {Generates alpha information} - procedure CreateAlpha; - {Removes the image transparency} - procedure RemoveTransparency; - {Transparent color} - property TransparentColor: TColor read GetTransparentColor write - SetTransparentColor; - {Add text chunk, TChunkTEXT, TChunkzTXT} - procedure AddtEXt(const Keyword, Text: String); - procedure AddzTXt(const Keyword, Text: String); - {$IFDEF UseDelphi} - {Saves to clipboard format (thanks to Antoine Pottern)} - procedure SaveToClipboardFormat(var AFormat: Word; var AData: THandle; - var APalette: HPalette); override; - procedure LoadFromClipboardFormat(AFormat: Word; AData: THandle; - APalette: HPalette); override; - {$ENDIF} - {Calling errors} - procedure RaiseError(ExceptionClass: ExceptClass; Text: String); - {Returns a scanline from png} - property Scanline[const Index: Integer]: Pointer read GetScanline; - {$IFDEF Store16bits} - property ExtraScanline[const Index: Integer]: Pointer read GetExtraScanline; - {$ENDIF} - property AlphaScanline[const Index: Integer]: pByteArray read GetAlphaScanline; - {Returns pointer to the header} - property Header: TChunkIHDR read GetHeader; - {Returns the transparency mode used by this png} - property TransparencyMode: TPNGTransparencyMode read GetTransparencyMode; - {Assigns from another object} - procedure Assign(Source: TPersistent);{$IFDEF UseDelphi}override;{$ENDIF} - {Assigns to another object} - procedure AssignTo(Dest: TPersistent);{$IFDEF UseDelphi}override;{$ENDIF} - {Assigns from a windows bitmap handle} - procedure AssignHandle(Handle: HBitmap; Transparent: Boolean; - TransparentColor: ColorRef); - {Draws the image into a canvas} - procedure Draw(ACanvas: TCanvas; const Rect: TRect); - {$IFDEF UseDelphi}override;{$ENDIF} - {Width and height properties} - property Width: Integer read GetWidth; - property Height: Integer read GetHeight; - {Returns if the image is interlaced} - property InterlaceMethod: TInterlaceMethod read fInterlaceMethod - write fInterlaceMethod; - {Filters to test to encode} - property Filters: TFilters read fFilters write fFilters; - {Maximum size for IDAT chunks, default and minimum is 65536} - property MaxIdatSize: Cardinal read fMaxIdatSize write SetMaxIdatSize; - {Property to return if the image is empty or not} - property Empty: Boolean read GetEmpty; - {Compression level} - property CompressionLevel: TCompressionLevel read fCompressionLevel - write fCompressionLevel; - {Access to the chunk list} - property Chunks: TPngList read fChunkList; - {Object being created and destroyed} - constructor Create; {$IFDEF UseDelphi}override;{$ENDIF} - destructor Destroy; override; - {$IFNDEF UseDelphi}procedure LoadFromFile(const Filename: String);{$ENDIF} - {$IFNDEF UseDelphi}procedure SaveToFile(const Filename: String);{$ENDIF} - procedure LoadFromStream(Stream: TStream); {$IFDEF UseDelphi}override;{$ENDIF} - procedure SaveToStream(Stream: TStream); {$IFDEF UseDelphi}override;{$ENDIF} - {Loading the image from resources} - procedure LoadFromResourceName(Instance: HInst; const Name: String); - procedure LoadFromResourceID(Instance: HInst; ResID: Integer); - {Access to the png pixels} - property Pixels[const X, Y: Integer]: TColor read GetPixels write SetPixels; - {Palette property} - {$IFNDEF UseDelphi}property Palette: HPalette read GetPalette;{$ENDIF} - end; - - {Chunk name object} - TChunkName = Array[0..3] of Char; - - {Global chunk object} - TChunk = class - private - {Contains data} - fData: Pointer; - fDataSize: Cardinal; - {Stores owner} - fOwner: TPngObject; - {Stores the chunk name} - fName: TChunkName; - {Returns pointer to the TChunkIHDR} - function GetHeader: TChunkIHDR; - {Used with property index} - function GetIndex: Integer; - {Should return chunk class/name} - class function GetName: String; virtual; - {Returns the chunk name} - function GetChunkName: String; - public - {Returns index from list} - property Index: Integer read GetIndex; - {Returns pointer to the TChunkIHDR} - property Header: TChunkIHDR read GetHeader; - {Resize the data} - procedure ResizeData(const NewSize: Cardinal); - {Returns data and size} - property Data: Pointer read fData; - property DataSize: Cardinal read fDataSize; - {Assigns from another TChunk} - procedure Assign(Source: TChunk); virtual; - {Returns owner} - property Owner: TPngObject read fOwner; - {Being destroyed/created} - constructor Create(Owner: TPngObject); virtual; - destructor Destroy; override; - {Returns chunk class/name} - property Name: String read GetChunkName; - {Loads the chunk from a stream} - function LoadFromStream(Stream: TStream; const ChunkName: TChunkName; - Size: Integer): Boolean; virtual; - {Saves the chunk to a stream} - function SaveData(Stream: TStream): Boolean; - function SaveToStream(Stream: TStream): Boolean; virtual; - end; - - {Chunk classes} - TChunkIEND = class(TChunk); {End chunk} - - {IHDR data} - pIHDRData = ^TIHDRData; - TIHDRData = packed record - Width, Height: Cardinal; - BitDepth, - ColorType, - CompressionMethod, - FilterMethod, - InterlaceMethod: Byte; - end; - - {Information header chunk} - TChunkIHDR = class(TChunk) - private - {Current image} - ImageHandle: HBitmap; - ImageDC: HDC; - - {Output windows bitmap} - HasPalette: Boolean; - BitmapInfo: TMaxBitmapInfo; - BytesPerRow: Integer; - {Stores the image bytes} - {$IFDEF Store16bits}ExtraImageData: Pointer;{$ENDIF} - ImageData: pointer; - ImageAlpha: Pointer; - - {Contains all the ihdr data} - IHDRData: TIHDRData; - protected - {Resizes the image data to fill the color type, bit depth, } - {width and height parameters} - procedure PrepareImageData; - {Release allocated ImageData memory} - procedure FreeImageData; - public - {Properties} - property Width: Cardinal read IHDRData.Width write IHDRData.Width; - property Height: Cardinal read IHDRData.Height write IHDRData.Height; - property BitDepth: Byte read IHDRData.BitDepth write IHDRData.BitDepth; - property ColorType: Byte read IHDRData.ColorType write IHDRData.ColorType; - property CompressionMethod: Byte read IHDRData.CompressionMethod - write IHDRData.CompressionMethod; - property FilterMethod: Byte read IHDRData.FilterMethod - write IHDRData.FilterMethod; - property InterlaceMethod: Byte read IHDRData.InterlaceMethod - write IHDRData.InterlaceMethod; - {Loads the chunk from a stream} - function LoadFromStream(Stream: TStream; const ChunkName: TChunkName; - Size: Integer): Boolean; override; - {Saves the chunk to a stream} - function SaveToStream(Stream: TStream): Boolean; override; - {Destructor/constructor} - constructor Create(Owner: TPngObject); override; - destructor Destroy; override; - {Assigns from another TChunk} - procedure Assign(Source: TChunk); override; - end; - - {Gamma chunk} - TChunkgAMA = class(TChunk) - private - {Returns/sets the value for the gamma chunk} - function GetValue: Cardinal; - procedure SetValue(const Value: Cardinal); - public - {Returns/sets gamma value} - property Gamma: Cardinal read GetValue write SetValue; - {Loading the chunk from a stream} - function LoadFromStream(Stream: TStream; const ChunkName: TChunkName; - Size: Integer): Boolean; override; - {Being created} - constructor Create(Owner: TPngObject); override; - {Assigns from another TChunk} - procedure Assign(Source: TChunk); override; - end; - - {ZLIB Decompression extra information} - TZStreamRec2 = packed record - {From ZLIB} - ZLIB: TZStreamRec; - {Additional info} - Data: Pointer; - fStream : TStream; - end; - - {Palette chunk} - TChunkPLTE = class(TChunk) - private - {Number of items in the palette} - fCount: Integer; - {Contains the palette handle} - function GetPaletteItem(Index: Byte): TRGBQuad; - public - {Returns the color for each item in the palette} - property Item[Index: Byte]: TRGBQuad read GetPaletteItem; - {Returns the number of items in the palette} - property Count: Integer read fCount; - {Loads the chunk from a stream} - function LoadFromStream(Stream: TStream; const ChunkName: TChunkName; - Size: Integer): Boolean; override; - {Saves the chunk to a stream} - function SaveToStream(Stream: TStream): Boolean; override; - {Assigns from another TChunk} - procedure Assign(Source: TChunk); override; - end; - - {Transparency information} - TChunktRNS = class(TChunk) - private - fBitTransparency: Boolean; - function GetTransparentColor: ColorRef; - {Returns the transparent color} - procedure SetTransparentColor(const Value: ColorRef); - public - {Palette values for transparency} - PaletteValues: Array[Byte] of Byte; - {Returns if it uses bit transparency} - property BitTransparency: Boolean read fBitTransparency; - {Returns the transparent color} - property TransparentColor: ColorRef read GetTransparentColor write - SetTransparentColor; - {Loads/saves the chunk from/to a stream} - function LoadFromStream(Stream: TStream; const ChunkName: TChunkName; - Size: Integer): Boolean; override; - function SaveToStream(Stream: TStream): Boolean; override; - {Assigns from another TChunk} - procedure Assign(Source: TChunk); override; - end; - - {Actual image information} - TChunkIDAT = class(TChunk) - private - {Holds another pointer to the TChunkIHDR} - Header: TChunkIHDR; - {Stores temporary image width and height} - ImageWidth, ImageHeight: Integer; - {Size in bytes of each line and offset} - Row_Bytes, Offset : Cardinal; - {Contains data for the lines} - Encode_Buffer: Array[0..5] of pByteArray; - Row_Buffer: Array[Boolean] of pByteArray; - {Variable to invert the Row_Buffer used} - RowUsed: Boolean; - {Ending position for the current IDAT chunk} - EndPos: Integer; - {Filter the current line} - procedure FilterRow; - {Filter to encode and returns the best filter} - function FilterToEncode: Byte; - {Reads ZLIB compressed data} - function IDATZlibRead(var ZLIBStream: TZStreamRec2; Buffer: Pointer; - Count: Integer; var EndPos: Integer; var crcfile: Cardinal): Integer; - {Compress and writes IDAT data} - procedure IDATZlibWrite(var ZLIBStream: TZStreamRec2; Buffer: Pointer; - const Length: Cardinal); - procedure FinishIDATZlib(var ZLIBStream: TZStreamRec2); - {Prepares the palette} - procedure PreparePalette; - protected - {Decode interlaced image} - procedure DecodeInterlacedAdam7(Stream: TStream; - var ZLIBStream: TZStreamRec2; const Size: Integer; var crcfile: Cardinal); - {Decode non interlaced imaged} - procedure DecodeNonInterlaced(Stream: TStream; - var ZLIBStream: TZStreamRec2; const Size: Integer; - var crcfile: Cardinal); - protected - {Encode non interlaced images} - procedure EncodeNonInterlaced(Stream: TStream; - var ZLIBStream: TZStreamRec2); - {Encode interlaced images} - procedure EncodeInterlacedAdam7(Stream: TStream; - var ZLIBStream: TZStreamRec2); - protected - {Memory copy methods to decode} - procedure CopyNonInterlacedRGB8( - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); - procedure CopyNonInterlacedRGB16( - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); - procedure CopyNonInterlacedPalette148( - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); - procedure CopyNonInterlacedPalette2( - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); - procedure CopyNonInterlacedGray2( - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); - procedure CopyNonInterlacedGrayscale16( - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); - procedure CopyNonInterlacedRGBAlpha8( - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); - procedure CopyNonInterlacedRGBAlpha16( - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); - procedure CopyNonInterlacedGrayscaleAlpha8( - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); - procedure CopyNonInterlacedGrayscaleAlpha16( - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); - procedure CopyInterlacedRGB8(const Pass: Byte; - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); - procedure CopyInterlacedRGB16(const Pass: Byte; - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); - procedure CopyInterlacedPalette148(const Pass: Byte; - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); - procedure CopyInterlacedPalette2(const Pass: Byte; - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); - procedure CopyInterlacedGray2(const Pass: Byte; - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); - procedure CopyInterlacedGrayscale16(const Pass: Byte; - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); - procedure CopyInterlacedRGBAlpha8(const Pass: Byte; - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); - procedure CopyInterlacedRGBAlpha16(const Pass: Byte; - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); - procedure CopyInterlacedGrayscaleAlpha8(const Pass: Byte; - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); - procedure CopyInterlacedGrayscaleAlpha16(const Pass: Byte; - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); - protected - {Memory copy methods to encode} - procedure EncodeNonInterlacedRGB8(Src, Dest, Trans: pChar); - procedure EncodeNonInterlacedRGB16(Src, Dest, Trans: pChar); - procedure EncodeNonInterlacedGrayscale16(Src, Dest, Trans: pChar); - procedure EncodeNonInterlacedPalette148(Src, Dest, Trans: pChar); - procedure EncodeNonInterlacedRGBAlpha8(Src, Dest, Trans: pChar); - procedure EncodeNonInterlacedRGBAlpha16(Src, Dest, Trans: pChar); - procedure EncodeNonInterlacedGrayscaleAlpha8(Src, Dest, Trans: pChar); - procedure EncodeNonInterlacedGrayscaleAlpha16(Src, Dest, Trans: pChar); - procedure EncodeInterlacedRGB8(const Pass: Byte; Src, Dest, Trans: pChar); - procedure EncodeInterlacedRGB16(const Pass: Byte; Src, Dest, Trans: pChar); - procedure EncodeInterlacedPalette148(const Pass: Byte; - Src, Dest, Trans: pChar); - procedure EncodeInterlacedGrayscale16(const Pass: Byte; - Src, Dest, Trans: pChar); - procedure EncodeInterlacedRGBAlpha8(const Pass: Byte; - Src, Dest, Trans: pChar); - procedure EncodeInterlacedRGBAlpha16(const Pass: Byte; - Src, Dest, Trans: pChar); - procedure EncodeInterlacedGrayscaleAlpha8(const Pass: Byte; - Src, Dest, Trans: pChar); - procedure EncodeInterlacedGrayscaleAlpha16(const Pass: Byte; - Src, Dest, Trans: pChar); - public - {Loads the chunk from a stream} - function LoadFromStream(Stream: TStream; const ChunkName: TChunkName; - Size: Integer): Boolean; override; - {Saves the chunk to a stream} - function SaveToStream(Stream: TStream): Boolean; override; - end; - - {Image last modification chunk} - TChunktIME = class(TChunk) - private - {Holds the variables} - fYear: Word; - fMonth, fDay, fHour, fMinute, fSecond: Byte; - public - {Returns/sets variables} - property Year: Word read fYear write fYear; - property Month: Byte read fMonth write fMonth; - property Day: Byte read fDay write fDay; - property Hour: Byte read fHour write fHour; - property Minute: Byte read fMinute write fMinute; - property Second: Byte read fSecond write fSecond; - {Loads the chunk from a stream} - function LoadFromStream(Stream: TStream; const ChunkName: TChunkName; - Size: Integer): Boolean; override; - {Saves the chunk to a stream} - function SaveToStream(Stream: TStream): Boolean; override; - end; - - {Textual data} - TChunktEXt = class(TChunk) - private - fKeyword, fText: String; - public - {Keyword and text} - property Keyword: String read fKeyword write fKeyword; - property Text: String read fText write fText; - {Loads the chunk from a stream} - function LoadFromStream(Stream: TStream; const ChunkName: TChunkName; - Size: Integer): Boolean; override; - {Saves the chunk to a stream} - function SaveToStream(Stream: TStream): Boolean; override; - {Assigns from another TChunk} - procedure Assign(Source: TChunk); override; - end; - - {zTXT chunk} - TChunkzTXt = class(TChunktEXt) - {Loads the chunk from a stream} - function LoadFromStream(Stream: TStream; const ChunkName: TChunkName; - Size: Integer): Boolean; override; - {Saves the chunk to a stream} - function SaveToStream(Stream: TStream): Boolean; override; - end; - -{Here we test if it's c++ builder or delphi version 3 or less} -{$IFDEF VER110}{$DEFINE DelphiBuilder3Less}{$ENDIF} -{$IFDEF VER100}{$DEFINE DelphiBuilder3Less}{$ENDIF} -{$IFDEF VER93}{$DEFINE DelphiBuilder3Less}{$ENDIF} -{$IFDEF VER90}{$DEFINE DelphiBuilder3Less}{$ENDIF} -{$IFDEF VER80}{$DEFINE DelphiBuilder3Less}{$ENDIF} - - -{Registers a new chunk class} -procedure RegisterChunk(ChunkClass: TChunkClass); -{Calculates crc} -function update_crc(crc: {$IFNDEF DelphiBuilder3Less}Cardinal{$ELSE}Integer - {$ENDIF}; buf: pByteArray; len: Integer): Cardinal; -{Invert bytes using assembly} -function ByteSwap(const a: integer): integer; - -implementation - -var - ChunkClasses: TPngPointerList; - {Table of CRCs of all 8-bit messages} - crc_table: Array[0..255] of Cardinal; - {Flag: has the table been computed? Initially false} - crc_table_computed: Boolean; - -{Draw transparent image using transparent color} -procedure DrawTransparentBitmap(dc: HDC; srcBits: Pointer; - var srcHeader: TBitmapInfoHeader; - srcBitmapInfo: pBitmapInfo; Rect: TRect; cTransparentColor: COLORREF); -var - cColor: COLORREF; - bmAndBack, bmAndObject, bmAndMem: HBITMAP; - bmBackOld, bmObjectOld, bmMemOld: HBITMAP; - hdcMem, hdcBack, hdcObject, hdcTemp: HDC; - ptSize, orgSize: TPOINT; - OldBitmap, DrawBitmap: HBITMAP; -begin - hdcTemp := CreateCompatibleDC(dc); - // Select the bitmap - DrawBitmap := CreateDIBitmap(dc, srcHeader, CBM_INIT, srcBits, srcBitmapInfo^, - DIB_RGB_COLORS); - OldBitmap := SelectObject(hdcTemp, DrawBitmap); - - // Sizes - OrgSize.x := abs(srcHeader.biWidth); - OrgSize.y := abs(srcHeader.biHeight); - ptSize.x := Rect.Right - Rect.Left; // Get width of bitmap - ptSize.y := Rect.Bottom - Rect.Top; // Get height of bitmap - - // Create some DCs to hold temporary data. - hdcBack := CreateCompatibleDC(dc); - hdcObject := CreateCompatibleDC(dc); - hdcMem := CreateCompatibleDC(dc); - - // Create a bitmap for each DC. DCs are required for a number of - // GDI functions. - - // Monochrome DCs - bmAndBack := CreateBitmap(ptSize.x, ptSize.y, 1, 1, nil); - bmAndObject := CreateBitmap(ptSize.x, ptSize.y, 1, 1, nil); - - bmAndMem := CreateCompatibleBitmap(dc, ptSize.x, ptSize.y); - - // Each DC must select a bitmap object to store pixel data. - bmBackOld := SelectObject(hdcBack, bmAndBack); - bmObjectOld := SelectObject(hdcObject, bmAndObject); - bmMemOld := SelectObject(hdcMem, bmAndMem); - - // Set the background color of the source DC to the color. - // contained in the parts of the bitmap that should be transparent - cColor := SetBkColor(hdcTemp, cTransparentColor); - - // Create the object mask for the bitmap by performing a BitBlt - // from the source bitmap to a monochrome bitmap. - StretchBlt(hdcObject, 0, 0, ptSize.x, ptSize.y, hdcTemp, 0, 0, - orgSize.x, orgSize.y, SRCCOPY); - - // Set the background color of the source DC back to the original - // color. - SetBkColor(hdcTemp, cColor); - - // Create the inverse of the object mask. - BitBlt(hdcBack, 0, 0, ptSize.x, ptSize.y, hdcObject, 0, 0, - NOTSRCCOPY); - - // Copy the background of the main DC to the destination. - BitBlt(hdcMem, 0, 0, ptSize.x, ptSize.y, dc, Rect.Left, Rect.Top, - SRCCOPY); - - // Mask out the places where the bitmap will be placed. - BitBlt(hdcMem, 0, 0, ptSize.x, ptSize.y, hdcObject, 0, 0, SRCAND); - - // Mask out the transparent colored pixels on the bitmap. -// BitBlt(hdcTemp, 0, 0, ptSize.x, ptSize.y, hdcBack, 0, 0, SRCAND); - StretchBlt(hdcTemp, 0, 0, OrgSize.x, OrgSize.y, hdcBack, 0, 0, - PtSize.x, PtSize.y, SRCAND); - - // XOR the bitmap with the background on the destination DC. - StretchBlt(hdcMem, 0, 0, ptSize.x, ptSize.y, hdcTemp, 0, 0, - OrgSize.x, OrgSize.y, SRCPAINT); - - // Copy the destination to the screen. - BitBlt(dc, Rect.Left, Rect.Top, ptSize.x, ptSize.y, hdcMem, 0, 0, - SRCCOPY); - - // Delete the memory bitmaps. - DeleteObject(SelectObject(hdcBack, bmBackOld)); - DeleteObject(SelectObject(hdcObject, bmObjectOld)); - DeleteObject(SelectObject(hdcMem, bmMemOld)); - DeleteObject(SelectObject(hdcTemp, OldBitmap)); - - // Delete the memory DCs. - DeleteDC(hdcMem); - DeleteDC(hdcBack); - DeleteDC(hdcObject); - DeleteDC(hdcTemp); -end; - -{Make the table for a fast CRC.} -procedure make_crc_table; -var - c: Cardinal; - n, k: Integer; -begin - - {fill the crc table} - for n := 0 to 255 do - begin - c := Cardinal(n); - for k := 0 to 7 do - begin - if Boolean(c and 1) then - c := $edb88320 xor (c shr 1) - else - c := c shr 1; - end; - crc_table[n] := c; - end; - - {The table has already being computated} - crc_table_computed := true; -end; - -{Update a running CRC with the bytes buf[0..len-1]--the CRC - should be initialized to all 1's, and the transmitted value - is the 1's complement of the final running CRC (see the - crc() routine below)).} -function update_crc(crc: {$IFNDEF DelphiBuilder3Less}Cardinal{$ELSE}Integer - {$ENDIF}; buf: pByteArray; len: Integer): Cardinal; -var - c: Cardinal; - n: Integer; -begin - c := crc; - - {Create the crc table in case it has not being computed yet} - if not crc_table_computed then make_crc_table; - - {Update} - for n := 0 to len - 1 do - c := crc_table[(c XOR buf^[n]) and $FF] XOR (c shr 8); - - {Returns} - Result := c; -end; - -{$IFNDEF UseDelphi} - function FileExists(Filename: String): Boolean; - var - FindFile: THandle; - FindData: TWin32FindData; - begin - FindFile := FindFirstFile(PChar(Filename), FindData); - Result := FindFile <> INVALID_HANDLE_VALUE; - if Result then Windows.FindClose(FindFile); - end; - - -{$ENDIF} - -{$IFNDEF UseDelphi} - {Exception implementation} - constructor Exception.Create(Msg: String); - begin - end; -{$ENDIF} - -{Calculates the paeth predictor} -function PaethPredictor(a, b, c: Byte): Byte; -var - pa, pb, pc: Integer; -begin - { a = left, b = above, c = upper left } - pa := abs(b - c); { distances to a, b, c } - pb := abs(a - c); - pc := abs(a + b - c * 2); - - { return nearest of a, b, c, breaking ties in order a, b, c } - if (pa <= pb) and (pa <= pc) then - Result := a - else - if pb <= pc then - Result := b - else - Result := c; -end; - -{Invert bytes using assembly} -function ByteSwap(const a: integer): integer; -asm - bswap eax -end; -function ByteSwap16(inp:word): word; -asm - bswap eax - shr eax, 16 -end; - -{Calculates number of bytes for the number of pixels using the} -{color mode in the paramenter} -function BytesForPixels(const Pixels: Integer; const ColorType, - BitDepth: Byte): Integer; -begin - case ColorType of - {Palette and grayscale contains a single value, for palette} - {an value of size 2^bitdepth pointing to the palette index} - {and grayscale the value from 0 to 2^bitdepth with color intesity} - COLOR_GRAYSCALE, COLOR_PALETTE: - Result := (Pixels * BitDepth + 7) div 8; - {RGB contains 3 values R, G, B with size 2^bitdepth each} - COLOR_RGB: - Result := (Pixels * BitDepth * 3) div 8; - {Contains one value followed by alpha value booth size 2^bitdepth} - COLOR_GRAYSCALEALPHA: - Result := (Pixels * BitDepth * 2) div 8; - {Contains four values size 2^bitdepth, Red, Green, Blue and alpha} - COLOR_RGBALPHA: - Result := (Pixels * BitDepth * 4) div 8; - else - Result := 0; - end {case ColorType} -end; - -type - pChunkClassInfo = ^TChunkClassInfo; - TChunkClassInfo = record - ClassName: TChunkClass; - end; - -{Register a chunk type} -procedure RegisterChunk(ChunkClass: TChunkClass); -var - NewClass: pChunkClassInfo; -begin - {In case the list object has not being created yet} - if ChunkClasses = nil then ChunkClasses := TPngPointerList.Create(nil); - - {Add this new class} - new(NewClass); - NewClass^.ClassName := ChunkClass; - ChunkClasses.Add(NewClass); -end; - -{Free chunk class list} -procedure FreeChunkClassList; -var - i: Integer; -begin - if (ChunkClasses <> nil) then - begin - FOR i := 0 TO ChunkClasses.Count - 1 do - Dispose(pChunkClassInfo(ChunkClasses.Item[i])); - ChunkClasses.Free; - end; -end; - -{Registering of common chunk classes} -procedure RegisterCommonChunks; -begin - {Important chunks} - RegisterChunk(TChunkIEND); - RegisterChunk(TChunkIHDR); - RegisterChunk(TChunkIDAT); - RegisterChunk(TChunkPLTE); - RegisterChunk(TChunkgAMA); - RegisterChunk(TChunktRNS); - - {Not so important chunks} - RegisterChunk(TChunktIME); - RegisterChunk(TChunktEXt); - RegisterChunk(TChunkzTXt); -end; - -{Creates a new chunk of this class} -function CreateClassChunk(Owner: TPngObject; Name: TChunkName): TChunk; -var - i : Integer; - NewChunk: TChunkClass; -begin - {Looks for this chunk} - NewChunk := TChunk; {In case there is no registered class for this} - - {Looks for this class in all registered chunks} - if Assigned(ChunkClasses) then - FOR i := 0 TO ChunkClasses.Count - 1 DO - begin - if pChunkClassInfo(ChunkClasses.Item[i])^.ClassName.GetName = Name then - begin - NewChunk := pChunkClassInfo(ChunkClasses.Item[i])^.ClassName; - break; - end; - end; - - {Returns chunk class} - Result := NewChunk.Create(Owner); - Result.fName := Name; -end; - -{ZLIB support} - -const - ZLIBAllocate = High(Word); - -{Initializes ZLIB for decompression} -function ZLIBInitInflate(Stream: TStream): TZStreamRec2; -begin - {Fill record} - Fillchar(Result, SIZEOF(TZStreamRec2), #0); - - {Set internal record information} - with Result do - begin - GetMem(Data, ZLIBAllocate); - fStream := Stream; - end; - - {Init decompression} - InflateInit_(Result.zlib, zlib_version, SIZEOF(TZStreamRec)); -end; - -{Initializes ZLIB for compression} -function ZLIBInitDeflate(Stream: TStream; - Level: TCompressionlevel; Size: Cardinal): TZStreamRec2; -begin - {Fill record} - Fillchar(Result, SIZEOF(TZStreamRec2), #0); - - {Set internal record information} - with Result, ZLIB do - begin - GetMem(Data, Size); - fStream := Stream; - next_out := Data; - avail_out := Size; - end; - - {Inits compression} - deflateInit_(Result.zlib, Level, zlib_version, sizeof(TZStreamRec)); -end; - -{Terminates ZLIB for compression} -procedure ZLIBTerminateDeflate(var ZLIBStream: TZStreamRec2); -begin - {Terminates decompression} - DeflateEnd(ZLIBStream.zlib); - {Free internal record} - FreeMem(ZLIBStream.Data, ZLIBAllocate); -end; - -{Terminates ZLIB for decompression} -procedure ZLIBTerminateInflate(var ZLIBStream: TZStreamRec2); -begin - {Terminates decompression} - InflateEnd(ZLIBStream.zlib); - {Free internal record} - FreeMem(ZLIBStream.Data, ZLIBAllocate); -end; - -{Decompresses ZLIB into a memory address} -function DecompressZLIB(const Input: Pointer; InputSize: Integer; - var Output: Pointer; var OutputSize: Integer; - var ErrorOutput: String): Boolean; -var - StreamRec : TZStreamRec; - Buffer : Array[Byte] of Byte; - InflateRet: Integer; -begin - with StreamRec do - begin - {Initializes} - Result := True; - OutputSize := 0; - - {Prepares the data to decompress} - FillChar(StreamRec, SizeOf(TZStreamRec), #0); - InflateInit_(StreamRec, zlib_version, SIZEOF(TZStreamRec)); - next_in := Input; - avail_in := InputSize; - - {Decodes data} - repeat - {In case it needs an output buffer} - if (avail_out = 0) then - begin - next_out := @Buffer; - avail_out := SizeOf(Buffer); - end {if (avail_out = 0)}; - - {Decompress and put in output} - InflateRet := inflate(StreamRec, 0); - if (InflateRet = Z_STREAM_END) or (InflateRet = 0) then - begin - {Reallocates output buffer} - inc(OutputSize, total_out); - if Output = nil then - GetMem(Output, OutputSize) else ReallocMem(Output, OutputSize); - {Copies the new data} - CopyMemory(Ptr(Longint(Output) + OutputSize - total_out), - @Buffer, total_out); - end {if (InflateRet = Z_STREAM_END) or (InflateRet = 0)} - {Now tests for errors} - else if InflateRet < 0 then - begin - Result := False; - ErrorOutput := StreamRec.msg; - InflateEnd(StreamRec); - Exit; - end {if InflateRet < 0} - until InflateRet = Z_STREAM_END; - - {Terminates decompression} - InflateEnd(StreamRec); - end {with StreamRec} - -end; - -{Compresses ZLIB into a memory address} -function CompressZLIB(Input: Pointer; InputSize, CompressionLevel: Integer; - var Output: Pointer; var OutputSize: Integer; - var ErrorOutput: String): Boolean; -var - StreamRec : TZStreamRec; - Buffer : Array[Byte] of Byte; - DeflateRet: Integer; -begin - with StreamRec do - begin - Result := True; {By default returns TRUE as everything might have gone ok} - OutputSize := 0; {Initialize} - {Prepares the data to compress} - FillChar(StreamRec, SizeOf(TZStreamRec), #0); - DeflateInit_(StreamRec, CompressionLevel,zlib_version, SIZEOF(TZStreamRec)); - - next_in := Input; - avail_in := InputSize; - - while avail_in > 0 do - begin - {When it needs new buffer to stores the compressed data} - if avail_out = 0 then - begin - {Restore buffer} - next_out := @Buffer; - avail_out := SizeOf(Buffer); - end {if avail_out = 0}; - - {Compresses} - DeflateRet := deflate(StreamRec, Z_FINISH); - - if (DeflateRet = Z_STREAM_END) or (DeflateRet = 0) then - begin - {Updates the output memory} - inc(OutputSize, total_out); - if Output = nil then - GetMem(Output, OutputSize) else ReallocMem(Output, OutputSize); - - {Copies the new data} - CopyMemory(Ptr(Longint(Output) + OutputSize - total_out), - @Buffer, total_out); - end {if (InflateRet = Z_STREAM_END) or (InflateRet = 0)} - {Now tests for errors} - else if DeflateRet < 0 then - begin - Result := False; - ErrorOutput := StreamRec.msg; - DeflateEnd(StreamRec); - Exit; - end {if InflateRet < 0} - - end {while avail_in > 0}; - - {Finishes compressing} - DeflateEnd(StreamRec); - end {with StreamRec} - -end; - -{TPngPointerList implementation} - -{Object being created} -constructor TPngPointerList.Create(AOwner: TPNGObject); -begin - inherited Create; {Let ancestor work} - {Holds owner} - fOwner := AOwner; - {Memory pointer not being used yet} - fMemory := nil; - {No items yet} - fCount := 0; -end; - -{Removes value from the list} -function TPngPointerList.Remove(Value: Pointer): Pointer; -var - I, Position: Integer; -begin - {Gets item position} - Position := -1; - FOR I := 0 TO Count - 1 DO - if Value = Item[I] then Position := I; - {In case a match was found} - if Position >= 0 then - begin - Result := Item[Position]; {Returns pointer} - {Remove item and move memory} - Dec(fCount); - if Position < Integer(FCount) then - System.Move(fMemory^[Position + 1], fMemory^[Position], - (Integer(fCount) - Position) * SizeOf(Pointer)); - end {if Position >= 0} else Result := nil -end; - -{Add a new value in the list} -procedure TPngPointerList.Add(Value: Pointer); -begin - Count := Count + 1; - Item[Count - 1] := Value; -end; - - -{Object being destroyed} -destructor TPngPointerList.Destroy; -begin - {Release memory if needed} - if fMemory <> nil then - FreeMem(fMemory, fCount * sizeof(Pointer)); - - {Free things} - inherited Destroy; -end; - -{Returns one item from the list} -function TPngPointerList.GetItem(Index: Cardinal): Pointer; -begin - if (Index <= Count - 1) then - Result := fMemory[Index] - else - {In case it's out of bounds} - Result := nil; -end; - -{Inserts a new item in the list} -procedure TPngPointerList.Insert(Value: Pointer; Position: Cardinal); -begin - if (Position < Count) then - begin - {Increase item count} - SetSize(Count + 1); - {Move other pointers} - if Position < Count then - System.Move(fMemory^[Position], fMemory^[Position + 1], - (Count - Position - 1) * SizeOf(Pointer)); - {Sets item} - Item[Position] := Value; - end; -end; - -{Sets one item from the list} -procedure TPngPointerList.SetItem(Index: Cardinal; const Value: Pointer); -begin - {If index is in bounds, set value} - if (Index <= Count - 1) then - fMemory[Index] := Value -end; - -{This method resizes the list} -procedure TPngPointerList.SetSize(const Size: Cardinal); -begin - {Sets the size} - if (fMemory = nil) and (Size > 0) then - GetMem(fMemory, Size * SIZEOF(Pointer)) - else - if Size > 0 then {Only realloc if the new size is greater than 0} - ReallocMem(fMemory, Size * SIZEOF(Pointer)) - else - {In case user is resize to 0 items} - begin - FreeMem(fMemory); - fMemory := nil; - end; - {Update count} - fCount := Size; -end; - -{TPNGList implementation} - -{Removes an item} -procedure TPNGList.RemoveChunk(Chunk: TChunk); -begin - Remove(Chunk); - Chunk.Free -end; - -{Add a new item} -function TPNGList.Add(ChunkClass: TChunkClass): TChunk; -var - IHDR: TChunkIHDR; - IEND: TChunkIEND; - - IDAT: TChunkIDAT; - PLTE: TChunkPLTE; -begin - Result := nil; {Default result} - {Adding these is not allowed} - if (ChunkClass = TChunkIHDR) or (ChunkClass = TChunkIDAT) or - (ChunkClass = TChunkPLTE) or (ChunkClass = TChunkIEND) then - fOwner.RaiseError(EPngError, EPNGCannotAddChunkText) - {Two of these is not allowed} - else if ((ChunkClass = TChunkgAMA) and (ItemFromClass(TChunkgAMA) <> nil)) or - ((ChunkClass = TChunktRNS) and (ItemFromClass(TChunktRNS) <> nil)) then - fOwner.RaiseError(EPngError, EPNGCannotAddChunkText) - {There must have an IEND and IHDR chunk} - else if (ItemFromClass(TChunkIEND) = nil) or - (ItemFromClass(TChunkIHDR) = nil) then - fOwner.RaiseError(EPngError, EPNGCannotAddInvalidImageText) - else - begin - {Get common chunks} - IHDR := ItemFromClass(TChunkIHDR) as TChunkIHDR; - IEND := ItemFromClass(TChunkIEND) as TChunkIEND; - {Create new chunk} - Result := ChunkClass.Create(Owner); - {Add to the list} - if (ChunkClass = TChunkgAMA) then - Insert(Result, IHDR.Index + 1) - {Transparency chunk (fix by Ian Boyd)} - else if (ChunkClass = TChunktRNS) then - begin - {Transparecy chunk must be after PLTE; before IDAT} - IDAT := ItemFromClass(TChunkIDAT) as TChunkIDAT; - PLTE := ItemFromClass(TChunkPLTE) as TChunkPLTE; - - if Assigned(PLTE) then - Insert(Result, PLTE.Index + 1) - else if Assigned(IDAT) then - Insert(Result, IDAT.Index) - else - Insert(Result, IHDR.Index + 1) - end - else {All other chunks} - Insert(Result, IEND.Index); - end {if} -end; - -{Returns item from the list} -function TPNGList.GetItem(Index: Cardinal): TChunk; -begin - Result := inherited GetItem(Index); -end; - -{Returns first item from the list using the class from parameter} -function TPNGList.ItemFromClass(ChunkClass: TChunkClass): TChunk; -var - i: Integer; -begin - Result := nil; {Initial result} - FOR i := 0 TO Count - 1 DO - {Test if this item has the same class} - if Item[i] is ChunkClass then - begin - {Returns this item and exit} - Result := Item[i]; - break; - end {if} -end; - -{$IFNDEF UseDelphi} - - {TStream implementation} - - {Copies all from another stream} - function TStream.CopyFrom(Source: TStream; Count: Cardinal): Cardinal; - const - MaxBytes = $f000; - var - Buffer: PChar; - BufSize, N: Cardinal; - begin - {If count is zero, copy everything from Source} - if Count = 0 then - begin - Source.Seek(0, soFromBeginning); - Count := Source.Size; - end; - - Result := Count; {Returns the number of bytes readed} - {Allocates memory} - if Count > MaxBytes then BufSize := MaxBytes else BufSize := Count; - GetMem(Buffer, BufSize); - - {Copy memory} - while Count > 0 do - begin - if Count > BufSize then N := BufSize else N := Count; - Source.Read(Buffer^, N); - Write(Buffer^, N); - dec(Count, N); - end; - - {Deallocates memory} - FreeMem(Buffer, BufSize); - end; - -{Set current stream position} -procedure TStream.SetPosition(const Value: Longint); -begin - Seek(Value, soFromBeginning); -end; - -{Returns position} -function TStream.GetPosition: Longint; -begin - Result := Seek(0, soFromCurrent); -end; - - {Returns stream size} -function TStream.GetSize: Longint; - var - Pos: Cardinal; - begin - Pos := Seek(0, soFromCurrent); - Result := Seek(0, soFromEnd); - Seek(Pos, soFromCurrent); - end; - - {TFileStream implementation} - - {Filestream object being created} - constructor TFileStream.Create(Filename: String; Mode: TFileStreamModeSet); - {Makes file mode} - function OpenMode: DWORD; - begin - Result := 0; - if fsmRead in Mode then Result := GENERIC_READ; - if (fsmWrite in Mode) or (fsmCreate in Mode) then - Result := Result OR GENERIC_WRITE; - end; - const - IsCreate: Array[Boolean] of Integer = (OPEN_ALWAYS, CREATE_ALWAYS); - begin - {Call ancestor} - inherited Create; - - {Create handle} - fHandle := CreateFile(PChar(Filename), OpenMode, FILE_SHARE_READ or - FILE_SHARE_WRITE, nil, IsCreate[fsmCreate in Mode], 0, 0); - {Store mode} - FileMode := Mode; - end; - - {Filestream object being destroyed} - destructor TFileStream.Destroy; - begin - {Terminates file and close} - if FileMode = [fsmWrite] then - SetEndOfFile(fHandle); - CloseHandle(fHandle); - - {Call ancestor} - inherited Destroy; - end; - - {Writes data to the file} - function TFileStream.Write(const Buffer; Count: Longint): Cardinal; - begin - if not WriteFile(fHandle, Buffer, Count, Result, nil) then - Result := 0; - end; - - {Reads data from the file} - function TFileStream.Read(var Buffer; Count: Longint): Cardinal; - begin - if not ReadFile(fHandle, Buffer, Count, Result, nil) then - Result := 0; - end; - - {Seeks the file position} - function TFileStream.Seek(Offset: Integer; Origin: Word): Longint; - begin - Result := SetFilePointer(fHandle, Offset, nil, Origin); - end; - - {Sets the size of the file} - procedure TFileStream.SetSize(const Value: Longint); - begin - Seek(Value, soFromBeginning); - SetEndOfFile(fHandle); - end; - - {TResourceStream implementation} - - {Creates the resource stream} - constructor TResourceStream.Create(Instance: HInst; const ResName: String; - ResType: PChar); - var - ResID: HRSRC; - ResGlobal: HGlobal; - begin - {Obtains the resource ID} - ResID := FindResource(hInstance, PChar(ResName), RT_RCDATA); - if ResID = 0 then raise EPNGError.Create(''); - {Obtains memory and size} - ResGlobal := LoadResource(hInstance, ResID); - Size := SizeOfResource(hInstance, ResID); - Memory := LockResource(ResGlobal); - if (ResGlobal = 0) or (Memory = nil) then EPNGError.Create(''); - end; - - - {Setting resource stream size is not supported} - procedure TResourceStream.SetSize(const Value: Integer); - begin - end; - - {Writing into a resource stream is not supported} - function TResourceStream.Write(const Buffer; Count: Integer): Cardinal; - begin - Result := 0; - end; - - {Reads data from the stream} - function TResourceStream.Read(var Buffer; Count: Integer): Cardinal; - begin - //Returns data - CopyMemory(@Buffer, Ptr(Longint(Memory) + Position), Count); - //Update position - inc(Position, Count); - //Returns - Result := Count; - end; - - {Seeks data} - function TResourceStream.Seek(Offset: Integer; Origin: Word): Longint; - begin - {Move depending on the origin} - case Origin of - soFromBeginning: Position := Offset; - soFromCurrent: inc(Position, Offset); - soFromEnd: Position := Size + Offset; - end; - - {Returns the current position} - Result := Position; - end; - -{$ENDIF} - -{TChunk implementation} - -{Resizes the data} -procedure TChunk.ResizeData(const NewSize: Cardinal); -begin - fDataSize := NewSize; - ReallocMem(fData, NewSize + 1); -end; - -{Returns index from list} -function TChunk.GetIndex: Integer; -var - i: Integer; -begin - Result := -1; {Avoiding warnings} - {Searches in the list} - FOR i := 0 TO Owner.Chunks.Count - 1 DO - if Owner.Chunks.Item[i] = Self then - begin - {Found match} - Result := i; - exit; - end {for i} -end; - -{Returns pointer to the TChunkIHDR} -function TChunk.GetHeader: TChunkIHDR; -begin - Result := Owner.Chunks.Item[0] as TChunkIHDR; -end; - -{Assigns from another TChunk} -procedure TChunk.Assign(Source: TChunk); -begin - {Copy properties} - fName := Source.fName; - {Set data size and realloc} - ResizeData(Source.fDataSize); - - {Copy data (if there's any)} - if fDataSize > 0 then CopyMemory(fData, Source.fData, fDataSize); -end; - -{Chunk being created} -constructor TChunk.Create(Owner: TPngObject); -var - ChunkName: String; -begin - {Ancestor create} - inherited Create; - - {If it's a registered class, set the chunk name based on the class} - {name. For instance, if the class name is TChunkgAMA, the GAMA part} - {will become the chunk name} - ChunkName := Copy(ClassName, Length('TChunk') + 1, Length(ClassName)); - if Length(ChunkName) = 4 then CopyMemory(@fName[0], @ChunkName[1], 4); - - {Initialize data holder} - GetMem(fData, 1); - fDataSize := 0; - {Record owner} - fOwner := Owner; -end; - -{Chunk being destroyed} -destructor TChunk.Destroy; -begin - {Free data holder} - FreeMem(fData, fDataSize + 1); - {Let ancestor destroy} - inherited Destroy; -end; - -{Returns the chunk name 1} -function TChunk.GetChunkName: String; -begin - Result := fName -end; - -{Returns the chunk name 2} -class function TChunk.GetName: String; -begin - {For avoid writing GetName for each TChunk descendent, by default for} - {classes which don't declare GetName, it will look for the class name} - {to extract the chunk kind. Example, if the class name is TChunkIEND } - {this method extracts and returns IEND} - Result := Copy(ClassName, Length('TChunk') + 1, Length(ClassName)); -end; - -{Saves the data to the stream} -function TChunk.SaveData(Stream: TStream): Boolean; -var - ChunkSize, ChunkCRC: Cardinal; -begin - {First, write the size for the following data in the chunk} - ChunkSize := ByteSwap(DataSize); - Stream.Write(ChunkSize, 4); - {The chunk name} - Stream.Write(fName, 4); - {If there is data for the chunk, write it} - if DataSize > 0 then Stream.Write(Data^, DataSize); - {Calculates and write CRC} - ChunkCRC := update_crc($ffffffff, @fName[0], 4); - ChunkCRC := Byteswap(update_crc(ChunkCRC, Data, DataSize) xor $ffffffff); - Stream.Write(ChunkCRC, 4); - - {Returns that everything went ok} - Result := TRUE; -end; - -{Saves the chunk to the stream} -function TChunk.SaveToStream(Stream: TStream): Boolean; -begin - Result := SaveData(Stream) -end; - - -{Loads the chunk from a stream} -function TChunk.LoadFromStream(Stream: TStream; const ChunkName: TChunkName; - Size: Integer): Boolean; -var - CheckCRC: Cardinal; - {$IFDEF CheckCRC}RightCRC: Cardinal;{$ENDIF} -begin - {Copies data from source} - ResizeData(Size); - if Size > 0 then Stream.Read(fData^, Size); - {Reads CRC} - Stream.Read(CheckCRC, 4); - CheckCrc := ByteSwap(CheckCRC); - - {Check if crc readed is valid} - {$IFDEF CheckCRC} - RightCRC := update_crc($ffffffff, @ChunkName[0], 4); - RightCRC := update_crc(RightCRC, fData, Size) xor $ffffffff; - Result := RightCRC = CheckCrc; - - {Handle CRC error} - if not Result then - begin - {In case it coult not load chunk} - Owner.RaiseError(EPngInvalidCRC, EPngInvalidCRCText); - exit; - end - {$ELSE}Result := TRUE; {$ENDIF} - -end; - -{TChunktIME implementation} - -{Chunk being loaded from a stream} -function TChunktIME.LoadFromStream(Stream: TStream; - const ChunkName: TChunkName; Size: Integer): Boolean; -begin - {Let ancestor load the data} - Result := inherited LoadFromStream(Stream, ChunkName, Size); - if not Result or (Size <> 7) then exit; {Size must be 7} - - {Reads data} - fYear := ((pByte(Longint(Data) )^) * 256)+ (pByte(Longint(Data) + 1)^); - fMonth := pByte(Longint(Data) + 2)^; - fDay := pByte(Longint(Data) + 3)^; - fHour := pByte(Longint(Data) + 4)^; - fMinute := pByte(Longint(Data) + 5)^; - fSecond := pByte(Longint(Data) + 6)^; -end; - -{Saving the chunk to a stream} -function TChunktIME.SaveToStream(Stream: TStream): Boolean; -begin - {Update data} - ResizeData(7); {Make sure the size is 7} - pWord(Data)^ := Year; - pByte(Longint(Data) + 2)^ := Month; - pByte(Longint(Data) + 3)^ := Day; - pByte(Longint(Data) + 4)^ := Hour; - pByte(Longint(Data) + 5)^ := Minute; - pByte(Longint(Data) + 6)^ := Second; - - {Let inherited save data} - Result := inherited SaveToStream(Stream); -end; - -{TChunkztXt implementation} - -{Loading the chunk from a stream} -function TChunkzTXt.LoadFromStream(Stream: TStream; - const ChunkName: TChunkName; Size: Integer): Boolean; -var - ErrorOutput: String; - CompressionMethod: Byte; - Output: Pointer; - OutputSize: Integer; -begin - {Load data from stream and validate} - Result := inherited LoadFromStream(Stream, ChunkName, Size); - if not Result or (Size < 4) then exit; - fKeyword := PChar(Data); {Get keyword and compression method bellow} - CompressionMethod := pByte(Longint(fKeyword) + Length(fKeyword))^; - fText := ''; - - {In case the compression is 0 (only one accepted by specs), reads it} - if CompressionMethod = 0 then - begin - Output := nil; - if DecompressZLIB(PChar(Longint(Data) + Length(fKeyword) + 2), - Size - Length(fKeyword) - 2, Output, OutputSize, ErrorOutput) then - begin - SetLength(fText, OutputSize); - CopyMemory(@fText[1], Output, OutputSize); - end {if DecompressZLIB(...}; - FreeMem(Output); - end {if CompressionMethod = 0} - -end; - -{Saving the chunk to a stream} -function TChunkztXt.SaveToStream(Stream: TStream): Boolean; -var - Output: Pointer; - OutputSize: Integer; - ErrorOutput: String; -begin - Output := nil; {Initializes output} - if fText = '' then fText := ' '; - - {Compresses the data} - if CompressZLIB(@fText[1], Length(fText), Owner.CompressionLevel, Output, - OutputSize, ErrorOutput) then - begin - {Size is length from keyword, plus a null character to divide} - {plus the compression method, plus the length of the text (zlib compressed)} - ResizeData(Length(fKeyword) + 2 + OutputSize); - - Fillchar(Data^, DataSize, #0); - {Copies the keyword data} - if Keyword <> '' then - CopyMemory(Data, @fKeyword[1], Length(Keyword)); - {Compression method 0 (inflate/deflate)} - pByte(Ptr(Longint(Data) + Length(Keyword) + 1))^ := 0; - if OutputSize > 0 then - CopyMemory(Ptr(Longint(Data) + Length(Keyword) + 2), Output, OutputSize); - - {Let ancestor calculate crc and save} - Result := SaveData(Stream); - end {if CompressZLIB(...} else Result := False; - - {Frees output} - if Output <> nil then FreeMem(Output) -end; - -{TChunktEXt implementation} - -{Assigns from another text chunk} -procedure TChunktEXt.Assign(Source: TChunk); -begin - fKeyword := TChunktEXt(Source).fKeyword; - fText := TChunktEXt(Source).fText; -end; - -{Loading the chunk from a stream} -function TChunktEXt.LoadFromStream(Stream: TStream; - const ChunkName: TChunkName; Size: Integer): Boolean; -begin - {Load data from stream and validate} - Result := inherited LoadFromStream(Stream, ChunkName, Size); - if not Result or (Size < 3) then exit; - {Get text} - fKeyword := PChar(Data); - SetLength(fText, Size - Length(fKeyword) - 1); - CopyMemory(@fText[1], Ptr(Longint(Data) + Length(fKeyword) + 1), - Length(fText)); -end; - -{Saving the chunk to a stream} -function TChunktEXt.SaveToStream(Stream: TStream): Boolean; -begin - {Size is length from keyword, plus a null character to divide} - {plus the length of the text} - ResizeData(Length(fKeyword) + 1 + Length(fText)); - Fillchar(Data^, DataSize, #0); - {Copy data} - if Keyword <> '' then - CopyMemory(Data, @fKeyword[1], Length(Keyword)); - if Text <> '' then - CopyMemory(Ptr(Longint(Data) + Length(Keyword) + 1), @fText[1], - Length(Text)); - {Let ancestor calculate crc and save} - Result := inherited SaveToStream(Stream); -end; - - -{TChunkIHDR implementation} - -{Chunk being created} -constructor TChunkIHDR.Create(Owner: TPngObject); -begin - {Call inherited} - inherited Create(Owner); - {Prepare pointers} - ImageHandle := 0; - ImageDC := 0; -end; - -{Chunk being destroyed} -destructor TChunkIHDR.Destroy; -begin - {Free memory} - FreeImageData(); - - {Calls TChunk destroy} - inherited Destroy; -end; - -{Assigns from another IHDR chunk} -procedure TChunkIHDR.Assign(Source: TChunk); -begin - {Copy the IHDR data} - if Source is TChunkIHDR then - begin - {Copy IHDR values} - IHDRData := TChunkIHDR(Source).IHDRData; - - {Prepare to hold data by filling BitmapInfo structure and} - {resizing ImageData and ImageAlpha memory allocations} - PrepareImageData(); - - {Copy image data} - CopyMemory(ImageData, TChunkIHDR(Source).ImageData, - BytesPerRow * Integer(Height)); - CopyMemory(ImageAlpha, TChunkIHDR(Source).ImageAlpha, - Integer(Width) * Integer(Height)); - - {Copy palette colors} - BitmapInfo.bmiColors := TChunkIHDR(Source).BitmapInfo.bmiColors; - end - else - Owner.RaiseError(EPNGError, EPNGCannotAssignChunkText); -end; - -{Release allocated image data} -procedure TChunkIHDR.FreeImageData; -begin - {Free old image data} - if ImageHandle <> 0 then DeleteObject(ImageHandle); - if ImageDC <> 0 then DeleteDC(ImageDC); - if ImageAlpha <> nil then FreeMem(ImageAlpha); - {$IFDEF Store16bits} - if ExtraImageData <> nil then FreeMem(ExtraImageData); - {$ENDIF} - ImageHandle := 0; ImageDC := 0; ImageAlpha := nil; ImageData := nil; -end; - -{Chunk being loaded from a stream} -function TChunkIHDR.LoadFromStream(Stream: TStream; const ChunkName: TChunkName; - Size: Integer): Boolean; -begin - {Let TChunk load it} - Result := inherited LoadFromStream(Stream, ChunkName, Size); - if not Result then Exit; - - {Now check values} - {Note: It's recommended by png specification to make sure that the size} - {must be 13 bytes to be valid, but some images with 14 bytes were found} - {which could be loaded by internet explorer and other tools} - if (fDataSize < SIZEOF(TIHdrData)) then - begin - {Ihdr must always have at least 13 bytes} - Result := False; - Owner.RaiseError(EPNGInvalidIHDR, EPNGInvalidIHDRText); - exit; - end; - - {Everything ok, reads IHDR} - IHDRData := pIHDRData(fData)^; - IHDRData.Width := ByteSwap(IHDRData.Width); - IHDRData.Height := ByteSwap(IHDRData.Height); - - {The width and height must not be larger than 65535 pixels} - if (IHDRData.Width > High(Word)) or (IHDRData.Height > High(Word)) then - begin - Result := False; - Owner.RaiseError(EPNGSizeExceeds, EPNGSizeExceedsText); - exit; - end {if IHDRData.Width > High(Word)}; - {Compression method must be 0 (inflate/deflate)} - if (IHDRData.CompressionMethod <> 0) then - begin - Result := False; - Owner.RaiseError(EPNGUnknownCompression, EPNGUnknownCompressionText); - exit; - end; - {Interlace must be either 0 (none) or 7 (adam7)} - if (IHDRData.InterlaceMethod <> 0) and (IHDRData.InterlaceMethod <> 1) then - begin - Result := False; - Owner.RaiseError(EPNGUnknownInterlace, EPNGUnknownInterlaceText); - exit; - end; - - {Updates owner properties} - Owner.InterlaceMethod := TInterlaceMethod(IHDRData.InterlaceMethod); - - {Prepares data to hold image} - PrepareImageData(); -end; - -{Saving the IHDR chunk to a stream} -function TChunkIHDR.SaveToStream(Stream: TStream): Boolean; -begin - {Ignore 2 bits images} - if BitDepth = 2 then BitDepth := 4; - - {It needs to do is update the data with the IHDR data} - {structure containing the write values} - ResizeData(SizeOf(TIHDRData)); - pIHDRData(fData)^ := IHDRData; - {..byteswap 4 byte types} - pIHDRData(fData)^.Width := ByteSwap(pIHDRData(fData)^.Width); - pIHDRData(fData)^.Height := ByteSwap(pIHDRData(fData)^.Height); - {..update interlace method} - pIHDRData(fData)^.InterlaceMethod := Byte(Owner.InterlaceMethod); - {..and then let the ancestor SaveToStream do the hard work} - Result := inherited SaveToStream(Stream); -end; - -{Resizes the image data to fill the color type, bit depth, } -{width and height parameters} -procedure TChunkIHDR.PrepareImageData(); - - {Set the bitmap info} - procedure SetInfo(const Bitdepth: Integer; const Palette: Boolean); - begin - - {Copy if the bitmap contain palette entries} - HasPalette := Palette; - {Initialize the structure with zeros} - fillchar(BitmapInfo, sizeof(BitmapInfo), #0); - {Fill the strucutre} - with BitmapInfo.bmiHeader do - begin - biSize := sizeof(TBitmapInfoHeader); - biHeight := Height; - biWidth := Width; - biPlanes := 1; - biBitCount := BitDepth; - biCompression := BI_RGB; - end {with BitmapInfo.bmiHeader} - end; -begin - {Prepare bitmap info header} - Fillchar(BitmapInfo, sizeof(TMaxBitmapInfo), #0); - {Release old image data} - FreeImageData(); - - {Obtain number of bits for each pixel} - case ColorType of - COLOR_GRAYSCALE, COLOR_PALETTE, COLOR_GRAYSCALEALPHA: - case BitDepth of - {These are supported by windows} - 1, 4, 8: SetInfo(BitDepth, TRUE); - {2 bits for each pixel is not supported by windows bitmap} - 2 : SetInfo(4, TRUE); - {Also 16 bits (2 bytes) for each pixel is not supported} - {and should be transormed into a 8 bit grayscale} - 16 : SetInfo(8, TRUE); - end; - {Only 1 byte (8 bits) is supported} - COLOR_RGB, COLOR_RGBALPHA: SetInfo(24, FALSE); - end {case ColorType}; - {Number of bytes for each scanline} - BytesPerRow := (((BitmapInfo.bmiHeader.biBitCount * Width) + 31) - and not 31) div 8; - - {Build array for alpha information, if necessary} - if (ColorType = COLOR_RGBALPHA) or (ColorType = COLOR_GRAYSCALEALPHA) then - begin - GetMem(ImageAlpha, Integer(Width) * Integer(Height)); - FillChar(ImageAlpha^, Integer(Width) * Integer(Height), #0); - end; - - {Build array for extra byte information} - {$IFDEF Store16bits} - if (BitDepth = 16) then - begin - GetMem(ExtraImageData, BytesPerRow * Integer(Height)); - FillChar(ExtraImageData^, BytesPerRow * Integer(Height), #0); - end; - {$ENDIF} - - {Creates the image to hold the data, CreateDIBSection does a better} - {work in allocating necessary memory} - ImageDC := CreateCompatibleDC(0); - ImageHandle := CreateDIBSection(ImageDC, pBitmapInfo(@BitmapInfo)^, - DIB_RGB_COLORS, ImageData, 0, 0); - - {Clears the old palette (if any)} - with Owner do - if TempPalette <> 0 then - begin - DeleteObject(TempPalette); - TempPalette := 0; - end {with Owner, if TempPalette <> 0}; - - {Build array and allocate bytes for each row} - zeromemory(ImageData, BytesPerRow * Integer(Height)); -end; - -{TChunktRNS implementation} - -{$IFNDEF UseDelphi} -function CompareMem(P1, P2: pByte; const Size: Integer): Boolean; -var i: Integer; -begin - Result := True; - for i := 1 to Size do - begin - if P1^ <> P2^ then Result := False; - inc(P1); inc(P2); - end {for i} -end; -{$ENDIF} - -{Sets the transpararent color} -procedure TChunktRNS.SetTransparentColor(const Value: ColorRef); -var - i: Byte; - LookColor: TRGBQuad; -begin - {Clears the palette values} - Fillchar(PaletteValues, SizeOf(PaletteValues), #0); - {Sets that it uses bit transparency} - fBitTransparency := True; - - - {Depends on the color type} - with Header do - case ColorType of - COLOR_GRAYSCALE: - begin - Self.ResizeData(2); - pWord(@PaletteValues[0])^ := ByteSwap16(GetRValue(Value)); - end; - COLOR_RGB: - begin - Self.ResizeData(6); - pWord(@PaletteValues[0])^ := ByteSwap16(GetRValue(Value)); - pWord(@PaletteValues[2])^ := ByteSwap16(GetGValue(Value)); - pWord(@PaletteValues[4])^ := ByteSwap16(GetBValue(Value)); - end; - COLOR_PALETTE: - begin - {Creates a RGBQuad to search for the color} - LookColor.rgbRed := GetRValue(Value); - LookColor.rgbGreen := GetGValue(Value); - LookColor.rgbBlue := GetBValue(Value); - {Look in the table for the entry} - for i := 0 to 255 do - if CompareMem(@BitmapInfo.bmiColors[i], @LookColor, 3) then - Break; - {Fill the transparency table} - Fillchar(PaletteValues, i, 255); - Self.ResizeData(i + 1) - - end - end {case / with}; - -end; - -{Returns the transparent color for the image} -function TChunktRNS.GetTransparentColor: ColorRef; -var - PaletteChunk: TChunkPLTE; - i: Integer; -begin - Result := 0; {Default: Unknown transparent color} - - {Depends on the color type} - with Header do - case ColorType of - COLOR_GRAYSCALE: - Result := RGB(PaletteValues[0], PaletteValues[0], - PaletteValues[0]); - COLOR_RGB: - Result := RGB(PaletteValues[1], PaletteValues[3], PaletteValues[5]); - COLOR_PALETTE: - begin - {Obtains the palette chunk} - PaletteChunk := Owner.Chunks.ItemFromClass(TChunkPLTE) as TChunkPLTE; - - {Looks for an entry with 0 transparency meaning that it is the} - {full transparent entry} - for i := 0 to Self.DataSize - 1 do - if PaletteValues[i] = 0 then - with PaletteChunk.GetPaletteItem(i) do - begin - Result := RGB(rgbRed, rgbGreen, rgbBlue); - break - end - end {COLOR_PALETTE} - end {case Header.ColorType}; -end; - -{Saving the chunk to a stream} -function TChunktRNS.SaveToStream(Stream: TStream): Boolean; -begin - {Copy palette into data buffer} - if DataSize <= 256 then - CopyMemory(fData, @PaletteValues[0], DataSize); - - Result := inherited SaveToStream(Stream); -end; - -{Assigns from another chunk} -procedure TChunktRNS.Assign(Source: TChunk); -begin - CopyMemory(@PaletteValues[0], @TChunkTrns(Source).PaletteValues[0], 256); - fBitTransparency := TChunkTrns(Source).fBitTransparency; - inherited Assign(Source); -end; - -{Loads the chunk from a stream} -function TChunktRNS.LoadFromStream(Stream: TStream; const ChunkName: TChunkName; - Size: Integer): Boolean; -var - i, Differ255: Integer; -begin - {Let inherited load} - Result := inherited LoadFromStream(Stream, ChunkName, Size); - - if not Result then Exit; - - {Make sure size is correct} - if Size > 256 then Owner.RaiseError(EPNGInvalidPalette, - EPNGInvalidPaletteText); - - {The unset items should have value 255} - Fillchar(PaletteValues[0], 256, 255); - {Copy the other values} - CopyMemory(@PaletteValues[0], fData, Size); - - {Create the mask if needed} - case Header.ColorType of - {Mask for grayscale and RGB} - COLOR_RGB, COLOR_GRAYSCALE: fBitTransparency := True; - COLOR_PALETTE: - begin - Differ255 := 0; {Count the entries with a value different from 255} - {Tests if it uses bit transparency} - for i := 0 to Size - 1 do - if PaletteValues[i] <> 255 then inc(Differ255); - - {If it has one value different from 255 it is a bit transparency} - fBitTransparency := (Differ255 = 1); - end {COLOR_PALETTE} - end {case Header.ColorType}; - -end; - -{Prepares the image palette} -procedure TChunkIDAT.PreparePalette; -var - Entries: Word; - j : Integer; -begin - {In case the image uses grayscale, build a grayscale palette} - with Header do - if (ColorType = COLOR_GRAYSCALE) or (ColorType = COLOR_GRAYSCALEALPHA) then - begin - {Calculate total number of palette entries} - Entries := (1 shl Byte(BitmapInfo.bmiHeader.biBitCount)); - - FOR j := 0 TO Entries - 1 DO - with BitmapInfo.bmiColors[j] do - begin - - {Calculate each palette entry} - rgbRed := fOwner.GammaTable[MulDiv(j, 255, Entries - 1)]; - rgbGreen := rgbRed; - rgbBlue := rgbRed; - end {with BitmapInfo.bmiColors[j]} - end {if ColorType = COLOR_GRAYSCALE..., with Header} -end; - -{Reads from ZLIB} -function TChunkIDAT.IDATZlibRead(var ZLIBStream: TZStreamRec2; - Buffer: Pointer; Count: Integer; var EndPos: Integer; - var crcfile: Cardinal): Integer; -var - ProcResult : Integer; - IDATHeader : Array[0..3] of char; - IDATCRC : Cardinal; -begin - {Uses internal record pointed by ZLIBStream to gather information} - with ZLIBStream, ZLIBStream.zlib do - begin - {Set the buffer the zlib will read into} - next_out := Buffer; - avail_out := Count; - - {Decode until it reach the Count variable} - while avail_out > 0 do - begin - {In case it needs more data and it's in the end of a IDAT chunk,} - {it means that there are more IDAT chunks} - if (fStream.Position = EndPos) and (avail_out > 0) and - (avail_in = 0) then - begin - {End this chunk by reading and testing the crc value} - fStream.Read(IDATCRC, 4); - - {$IFDEF CheckCRC} - if crcfile xor $ffffffff <> Cardinal(ByteSwap(IDATCRC)) then - begin - Result := -1; - Owner.RaiseError(EPNGInvalidCRC, EPNGInvalidCRCText); - exit; - end; - {$ENDIF} - - {Start reading the next chunk} - fStream.Read(EndPos, 4); {Reads next chunk size} - fStream.Read(IDATHeader[0], 4); {Next chunk header} - {It must be a IDAT chunk since image data is required and PNG} - {specification says that multiple IDAT chunks must be consecutive} - if IDATHeader <> 'IDAT' then - begin - Owner.RaiseError(EPNGMissingMultipleIDAT, EPNGMissingMultipleIDATText); - result := -1; - exit; - end; - - {Calculate chunk name part of the crc} - {$IFDEF CheckCRC} - crcfile := update_crc($ffffffff, @IDATHeader[0], 4); - {$ENDIF} - EndPos := fStream.Position + ByteSwap(EndPos); - end; - - - {In case it needs compressed data to read from} - if avail_in = 0 then - begin - {In case it's trying to read more than it is avaliable} - if fStream.Position + ZLIBAllocate > EndPos then - avail_in := fStream.Read(Data^, EndPos - fStream.Position) - else - avail_in := fStream.Read(Data^, ZLIBAllocate); - {Update crc} - {$IFDEF CheckCRC} - crcfile := update_crc(crcfile, Data, avail_in); - {$ENDIF} - - {In case there is no more compressed data to read from} - if avail_in = 0 then - begin - Result := Count - avail_out; - Exit; - end; - - {Set next buffer to read and record current position} - next_in := Data; - - end {if avail_in = 0}; - - ProcResult := inflate(zlib, 0); - - {In case the result was not sucessfull} - if (ProcResult < 0) then - begin - Result := -1; - Owner.RaiseError(EPNGZLIBError, - EPNGZLIBErrorText + zliberrors[procresult]); - exit; - end; - - end {while avail_out > 0}; - - end {with}; - - {If everything gone ok, it returns the count bytes} - Result := Count; -end; - -{TChunkIDAT implementation} - -const - {Adam 7 interlacing values} - RowStart: array[0..6] of Integer = (0, 0, 4, 0, 2, 0, 1); - ColumnStart: array[0..6] of Integer = (0, 4, 0, 2, 0, 1, 0); - RowIncrement: array[0..6] of Integer = (8, 8, 8, 4, 4, 2, 2); - ColumnIncrement: array[0..6] of Integer = (8, 8, 4, 4, 2, 2, 1); - -{Copy interlaced images with 1 byte for R, G, B} -procedure TChunkIDAT.CopyInterlacedRGB8(const Pass: Byte; - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); -var - Col: Integer; -begin - {Get first column and enter in loop} - Col := ColumnStart[Pass]; - Dest := pChar(Longint(Dest) + Col * 3); - repeat - {Copy this row} - Byte(Dest^) := fOwner.GammaTable[pByte(Longint(Src) + 2)^]; inc(Dest); - Byte(Dest^) := fOwner.GammaTable[pByte(Longint(Src) + 1)^]; inc(Dest); - Byte(Dest^) := fOwner.GammaTable[pByte(Longint(Src) )^]; inc(Dest); - - {Move to next column} - inc(Src, 3); - inc(Dest, ColumnIncrement[Pass] * 3 - 3); - inc(Col, ColumnIncrement[Pass]); - until Col >= ImageWidth; -end; - -{Copy interlaced images with 2 bytes for R, G, B} -procedure TChunkIDAT.CopyInterlacedRGB16(const Pass: Byte; - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); -var - Col: Integer; -begin - {Get first column and enter in loop} - Col := ColumnStart[Pass]; - Dest := pChar(Longint(Dest) + Col * 3); - repeat - {Copy this row} - Byte(Dest^) := Owner.GammaTable[pByte(Longint(Src) + 4)^]; inc(Dest); - Byte(Dest^) := Owner.GammaTable[pByte(Longint(Src) + 2)^]; inc(Dest); - Byte(Dest^) := Owner.GammaTable[pByte(Longint(Src) )^]; inc(Dest); - {$IFDEF Store16bits} - {Copy extra pixel values} - Byte(Extra^) := fOwner.GammaTable[pByte(Longint(Src) + 5)^]; inc(Extra); - Byte(Extra^) := fOwner.GammaTable[pByte(Longint(Src) + 3)^]; inc(Extra); - Byte(Extra^) := fOwner.GammaTable[pByte(Longint(Src) + 1)^]; inc(Extra); - {$ENDIF} - - {Move to next column} - inc(Src, 6); - inc(Dest, ColumnIncrement[Pass] * 3 - 3); - inc(Col, ColumnIncrement[Pass]); - until Col >= ImageWidth; -end; - -{Copy ímages with palette using bit depths 1, 4 or 8} -procedure TChunkIDAT.CopyInterlacedPalette148(const Pass: Byte; - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); -const - BitTable: Array[1..8] of Integer = ($1, $3, 0, $F, 0, 0, 0, $FF); - StartBit: Array[1..8] of Integer = (7 , 0 , 0, 4, 0, 0, 0, 0); -var - CurBit, Col: Integer; - Dest2: PChar; -begin - {Get first column and enter in loop} - Col := ColumnStart[Pass]; - repeat - {Copy data} - CurBit := StartBit[Header.BitDepth]; - repeat - {Adjust pointer to pixel byte bounds} - Dest2 := pChar(Longint(Dest) + (Header.BitDepth * Col) div 8); - {Copy data} - Byte(Dest2^) := Byte(Dest2^) or - ( ((Byte(Src^) shr CurBit) and BitTable[Header.BitDepth]) - shl (StartBit[Header.BitDepth] - (Col * Header.BitDepth mod 8))); - - {Move to next column} - inc(Col, ColumnIncrement[Pass]); - {Will read next bits} - dec(CurBit, Header.BitDepth); - until CurBit < 0; - - {Move to next byte in source} - inc(Src); - until Col >= ImageWidth; -end; - -{Copy ímages with palette using bit depth 2} -procedure TChunkIDAT.CopyInterlacedPalette2(const Pass: Byte; Src, Dest, - Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); -var - CurBit, Col: Integer; - Dest2: PChar; -begin - {Get first column and enter in loop} - Col := ColumnStart[Pass]; - repeat - {Copy data} - CurBit := 6; - repeat - {Adjust pointer to pixel byte bounds} - Dest2 := pChar(Longint(Dest) + Col div 2); - {Copy data} - Byte(Dest2^) := Byte(Dest2^) or (((Byte(Src^) shr CurBit) and $3) - shl (4 - (4 * Col) mod 8)); - {Move to next column} - inc(Col, ColumnIncrement[Pass]); - {Will read next bits} - dec(CurBit, 2); - until CurBit < 0; - - {Move to next byte in source} - inc(Src); - until Col >= ImageWidth; -end; - -{Copy ímages with grayscale using bit depth 2} -procedure TChunkIDAT.CopyInterlacedGray2(const Pass: Byte; - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); -var - CurBit, Col: Integer; - Dest2: PChar; -begin - {Get first column and enter in loop} - Col := ColumnStart[Pass]; - repeat - {Copy data} - CurBit := 6; - repeat - {Adjust pointer to pixel byte bounds} - Dest2 := pChar(Longint(Dest) + Col div 2); - {Copy data} - Byte(Dest2^) := Byte(Dest2^) or ((((Byte(Src^) shr CurBit) shl 2) and $F) - shl (4 - (Col*4) mod 8)); - {Move to next column} - inc(Col, ColumnIncrement[Pass]); - {Will read next bits} - dec(CurBit, 2); - until CurBit < 0; - - {Move to next byte in source} - inc(Src); - until Col >= ImageWidth; -end; - -{Copy ímages with palette using 2 bytes for each pixel} -procedure TChunkIDAT.CopyInterlacedGrayscale16(const Pass: Byte; - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); -var - Col: Integer; -begin - {Get first column and enter in loop} - Col := ColumnStart[Pass]; - Dest := pChar(Longint(Dest) + Col); - repeat - {Copy this row} - Dest^ := Src^; inc(Dest); - {$IFDEF Store16bits} - Extra^ := pChar(Longint(Src) + 1)^; inc(Extra); - {$ENDIF} - - {Move to next column} - inc(Src, 2); - inc(Dest, ColumnIncrement[Pass] - 1); - inc(Col, ColumnIncrement[Pass]); - until Col >= ImageWidth; -end; - -{Decodes interlaced RGB alpha with 1 byte for each sample} -procedure TChunkIDAT.CopyInterlacedRGBAlpha8(const Pass: Byte; - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); -var - Col: Integer; -begin - {Get first column and enter in loop} - Col := ColumnStart[Pass]; - Dest := pChar(Longint(Dest) + Col * 3); - Trans := pChar(Longint(Trans) + Col); - repeat - {Copy this row and alpha value} - Trans^ := pChar(Longint(Src) + 3)^; - Byte(Dest^) := fOwner.GammaTable[pByte(Longint(Src) + 2)^]; inc(Dest); - Byte(Dest^) := fOwner.GammaTable[pByte(Longint(Src) + 1)^]; inc(Dest); - Byte(Dest^) := fOwner.GammaTable[pByte(Longint(Src) )^]; inc(Dest); - - {Move to next column} - inc(Src, 4); - inc(Dest, ColumnIncrement[Pass] * 3 - 3); - inc(Trans, ColumnIncrement[Pass]); - inc(Col, ColumnIncrement[Pass]); - until Col >= ImageWidth; -end; - -{Decodes interlaced RGB alpha with 2 bytes for each sample} -procedure TChunkIDAT.CopyInterlacedRGBAlpha16(const Pass: Byte; - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); -var - Col: Integer; -begin - {Get first column and enter in loop} - Col := ColumnStart[Pass]; - Dest := pChar(Longint(Dest) + Col * 3); - Trans := pChar(Longint(Trans) + Col); - repeat - {Copy this row and alpha value} - Trans^ := pChar(Longint(Src) + 6)^; - Byte(Dest^) := fOwner.GammaTable[pByte(Longint(Src) + 4)^]; inc(Dest); - Byte(Dest^) := fOwner.GammaTable[pByte(Longint(Src) + 2)^]; inc(Dest); - Byte(Dest^) := fOwner.GammaTable[pByte(Longint(Src) )^]; inc(Dest); - {$IFDEF Store16bits} - {Copy extra pixel values} - Byte(Extra^) := fOwner.GammaTable[pByte(Longint(Src) + 5)^]; inc(Extra); - Byte(Extra^) := fOwner.GammaTable[pByte(Longint(Src) + 3)^]; inc(Extra); - Byte(Extra^) := fOwner.GammaTable[pByte(Longint(Src) + 1)^]; inc(Extra); - {$ENDIF} - - {Move to next column} - inc(Src, 8); - inc(Dest, ColumnIncrement[Pass] * 3 - 3); - inc(Trans, ColumnIncrement[Pass]); - inc(Col, ColumnIncrement[Pass]); - until Col >= ImageWidth; -end; - -{Decodes 8 bit grayscale image followed by an alpha sample} -procedure TChunkIDAT.CopyInterlacedGrayscaleAlpha8(const Pass: Byte; - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); -var - Col: Integer; -begin - {Get first column, pointers to the data and enter in loop} - Col := ColumnStart[Pass]; - Dest := pChar(Longint(Dest) + Col); - Trans := pChar(Longint(Trans) + Col); - repeat - {Copy this grayscale value and alpha} - Dest^ := Src^; inc(Src); - Trans^ := Src^; inc(Src); - - {Move to next column} - inc(Dest, ColumnIncrement[Pass]); - inc(Trans, ColumnIncrement[Pass]); - inc(Col, ColumnIncrement[Pass]); - until Col >= ImageWidth; -end; - -{Decodes 16 bit grayscale image followed by an alpha sample} -procedure TChunkIDAT.CopyInterlacedGrayscaleAlpha16(const Pass: Byte; - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); -var - Col: Integer; -begin - {Get first column, pointers to the data and enter in loop} - Col := ColumnStart[Pass]; - Dest := pChar(Longint(Dest) + Col); - Trans := pChar(Longint(Trans) + Col); - repeat - {$IFDEF Store16bits} - Extra^ := pChar(Longint(Src) + 1)^; inc(Extra); - {$ENDIF} - {Copy this grayscale value and alpha, transforming 16 bits into 8} - Dest^ := Src^; inc(Src, 2); - Trans^ := Src^; inc(Src, 2); - - {Move to next column} - inc(Dest, ColumnIncrement[Pass]); - inc(Trans, ColumnIncrement[Pass]); - inc(Col, ColumnIncrement[Pass]); - until Col >= ImageWidth; -end; - -{Decodes an interlaced image} -procedure TChunkIDAT.DecodeInterlacedAdam7(Stream: TStream; - var ZLIBStream: TZStreamRec2; const Size: Integer; var crcfile: Cardinal); -var - CurrentPass: Byte; - PixelsThisRow: Integer; - CurrentRow: Integer; - Trans, Data{$IFDEF Store16bits}, Extra{$ENDIF}: pChar; - CopyProc: procedure(const Pass: Byte; Src, Dest, - Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar) of object; -begin - - CopyProc := nil; {Initialize} - {Determine method to copy the image data} - case Header.ColorType of - {R, G, B values for each pixel} - COLOR_RGB: - case Header.BitDepth of - 8: CopyProc := CopyInterlacedRGB8; - 16: CopyProc := CopyInterlacedRGB16; - end {case Header.BitDepth}; - {Palette} - COLOR_PALETTE, COLOR_GRAYSCALE: - case Header.BitDepth of - 1, 4, 8: CopyProc := CopyInterlacedPalette148; - 2 : if Header.ColorType = COLOR_PALETTE then - CopyProc := CopyInterlacedPalette2 - else - CopyProc := CopyInterlacedGray2; - 16 : CopyProc := CopyInterlacedGrayscale16; - end; - {RGB followed by alpha} - COLOR_RGBALPHA: - case Header.BitDepth of - 8: CopyProc := CopyInterlacedRGBAlpha8; - 16: CopyProc := CopyInterlacedRGBAlpha16; - end; - {Grayscale followed by alpha} - COLOR_GRAYSCALEALPHA: - case Header.BitDepth of - 8: CopyProc := CopyInterlacedGrayscaleAlpha8; - 16: CopyProc := CopyInterlacedGrayscaleAlpha16; - end; - end {case Header.ColorType}; - - {Adam7 method has 7 passes to make the final image} - FOR CurrentPass := 0 TO 6 DO - begin - {Calculates the number of pixels and bytes for this pass row} - PixelsThisRow := (ImageWidth - ColumnStart[CurrentPass] + - ColumnIncrement[CurrentPass] - 1) div ColumnIncrement[CurrentPass]; - Row_Bytes := BytesForPixels(PixelsThisRow, Header.ColorType, - Header.BitDepth); - {Clear buffer for this pass} - ZeroMemory(Row_Buffer[not RowUsed], Row_Bytes); - - {Get current row index} - CurrentRow := RowStart[CurrentPass]; - {Get a pointer to the current row image data} - Data := Ptr(Longint(Header.ImageData) + Header.BytesPerRow * - (ImageHeight - 1 - CurrentRow)); - Trans := Ptr(Longint(Header.ImageAlpha) + ImageWidth * CurrentRow); - {$IFDEF Store16bits} - Extra := Ptr(Longint(Header.ExtraImageData) + Header.BytesPerRow * - (ImageHeight - 1 - CurrentRow)); - {$ENDIF} - - if Row_Bytes > 0 then {There must have bytes for this interlaced pass} - while CurrentRow < ImageHeight do - begin - {Reads this line and filter} - if IDATZlibRead(ZLIBStream, @Row_Buffer[RowUsed][0], Row_Bytes + 1, - EndPos, CRCFile) = 0 then break; - - FilterRow; - {Copy image data} - - CopyProc(CurrentPass, @Row_Buffer[RowUsed][1], Data, Trans - {$IFDEF Store16bits}, Extra{$ENDIF}); - - {Use the other RowBuffer item} - RowUsed := not RowUsed; - - {Move to the next row} - inc(CurrentRow, RowIncrement[CurrentPass]); - {Move pointer to the next line} - dec(Data, RowIncrement[CurrentPass] * Header.BytesPerRow); - inc(Trans, RowIncrement[CurrentPass] * ImageWidth); - {$IFDEF Store16bits} - dec(Extra, RowIncrement[CurrentPass] * Header.BytesPerRow); - {$ENDIF} - end {while CurrentRow < ImageHeight}; - - end {FOR CurrentPass}; - -end; - -{Copy 8 bits RGB image} -procedure TChunkIDAT.CopyNonInterlacedRGB8( - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); -var - I: Integer; -begin - FOR I := 1 TO ImageWidth DO - begin - {Copy pixel values} - Byte(Dest^) := fOwner.GammaTable[pByte(Longint(Src) + 2)^]; inc(Dest); - Byte(Dest^) := fOwner.GammaTable[pByte(Longint(Src) + 1)^]; inc(Dest); - Byte(Dest^) := fOwner.GammaTable[pByte(Longint(Src) )^]; inc(Dest); - {Move to next pixel} - inc(Src, 3); - end {for I} -end; - -{Copy 16 bits RGB image} -procedure TChunkIDAT.CopyNonInterlacedRGB16( - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); -var - I: Integer; -begin - FOR I := 1 TO ImageWidth DO - begin - //Since windows does not supports 2 bytes for - //each R, G, B value, the method will read only 1 byte from it - {Copy pixel values} - Byte(Dest^) := fOwner.GammaTable[pByte(Longint(Src) + 4)^]; inc(Dest); - Byte(Dest^) := fOwner.GammaTable[pByte(Longint(Src) + 2)^]; inc(Dest); - Byte(Dest^) := fOwner.GammaTable[pByte(Longint(Src) )^]; inc(Dest); - {$IFDEF Store16bits} - {Copy extra pixel values} - Byte(Extra^) := fOwner.GammaTable[pByte(Longint(Src) + 5)^]; inc(Extra); - Byte(Extra^) := fOwner.GammaTable[pByte(Longint(Src) + 3)^]; inc(Extra); - Byte(Extra^) := fOwner.GammaTable[pByte(Longint(Src) + 1)^]; inc(Extra); - {$ENDIF} - - {Move to next pixel} - inc(Src, 6); - end {for I} -end; - -{Copy types using palettes (1, 4 or 8 bits per pixel)} -procedure TChunkIDAT.CopyNonInterlacedPalette148( - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); -begin - {It's simple as copying the data} - CopyMemory(Dest, Src, Row_Bytes); -end; - -{Copy grayscale types using 2 bits for each pixel} -procedure TChunkIDAT.CopyNonInterlacedGray2( - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); -var - i: Integer; -begin - {2 bits is not supported, this routine will converted into 4 bits} - FOR i := 1 TO Row_Bytes do - begin - Byte(Dest^) := ((Byte(Src^) shr 2) and $F) or ((Byte(Src^)) and $F0); inc(Dest); - Byte(Dest^) := ((Byte(Src^) shl 2) and $F) or ((Byte(Src^) shl 4) and $F0); inc(Dest); - inc(Src); - end {FOR i} -end; - -{Copy types using palette with 2 bits for each pixel} -procedure TChunkIDAT.CopyNonInterlacedPalette2( - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); -var - i: Integer; -begin - {2 bits is not supported, this routine will converted into 4 bits} - FOR i := 1 TO Row_Bytes do - begin - Byte(Dest^) := ((Byte(Src^) shr 4) and $3) or ((Byte(Src^) shr 2) and $30); inc(Dest); - Byte(Dest^) := (Byte(Src^) and $3) or ((Byte(Src^) shl 2) and $30); inc(Dest); - inc(Src); - end {FOR i} -end; - -{Copy grayscale images with 16 bits} -procedure TChunkIDAT.CopyNonInterlacedGrayscale16( - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); -var - I: Integer; -begin - FOR I := 1 TO ImageWidth DO - begin - {Windows does not supports 16 bits for each pixel in grayscale} - {mode, so reduce to 8} - Dest^ := Src^; inc(Dest); - {$IFDEF Store16bits} - Extra^ := pChar(Longint(Src) + 1)^; inc(Extra); - {$ENDIF} - - {Move to next pixel} - inc(Src, 2); - end {for I} -end; - -{Copy 8 bits per sample RGB images followed by an alpha byte} -procedure TChunkIDAT.CopyNonInterlacedRGBAlpha8( - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); -var - i: Integer; -begin - FOR I := 1 TO ImageWidth DO - begin - {Copy pixel values and transparency} - Trans^ := pChar(Longint(Src) + 3)^; - Byte(Dest^) := fOwner.GammaTable[pByte(Longint(Src) + 2)^]; inc(Dest); - Byte(Dest^) := fOwner.GammaTable[pByte(Longint(Src) + 1)^]; inc(Dest); - Byte(Dest^) := fOwner.GammaTable[pByte(Longint(Src) )^]; inc(Dest); - {Move to next pixel} - inc(Src, 4); inc(Trans); - end {for I} -end; - -{Copy 16 bits RGB image with alpha using 2 bytes for each sample} -procedure TChunkIDAT.CopyNonInterlacedRGBAlpha16( - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); -var - I: Integer; -begin - FOR I := 1 TO ImageWidth DO - begin - //Copy rgb and alpha values (transforming from 16 bits to 8 bits) - {Copy pixel values} - Trans^ := pChar(Longint(Src) + 6)^; - Byte(Dest^) := fOwner.GammaTable[pByte(Longint(Src) + 4)^]; inc(Dest); - Byte(Dest^) := fOwner.GammaTable[pByte(Longint(Src) + 2)^]; inc(Dest); - Byte(Dest^) := fOwner.GammaTable[pByte(Longint(Src) )^]; inc(Dest); - {$IFDEF Store16bits} - {Copy extra pixel values} - Byte(Extra^) := fOwner.GammaTable[pByte(Longint(Src) + 5)^]; inc(Extra); - Byte(Extra^) := fOwner.GammaTable[pByte(Longint(Src) + 3)^]; inc(Extra); - Byte(Extra^) := fOwner.GammaTable[pByte(Longint(Src) + 1)^]; inc(Extra); - {$ENDIF} - {Move to next pixel} - inc(Src, 8); inc(Trans); - end {for I} -end; - -{Copy 8 bits per sample grayscale followed by alpha} -procedure TChunkIDAT.CopyNonInterlacedGrayscaleAlpha8( - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); -var - I: Integer; -begin - FOR I := 1 TO ImageWidth DO - begin - {Copy alpha value and then gray value} - Dest^ := Src^; inc(Src); - Trans^ := Src^; inc(Src); - inc(Dest); inc(Trans); - end; -end; - -{Copy 16 bits per sample grayscale followed by alpha} -procedure TChunkIDAT.CopyNonInterlacedGrayscaleAlpha16( - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar); -var - I: Integer; -begin - FOR I := 1 TO ImageWidth DO - begin - {Copy alpha value and then gray value} - {$IFDEF Store16bits} - Extra^ := pChar(Longint(Src) + 1)^; inc(Extra); - {$ENDIF} - Dest^ := Src^; inc(Src, 2); - Trans^ := Src^; inc(Src, 2); - inc(Dest); inc(Trans); - end; -end; - -{Decode non interlaced image} -procedure TChunkIDAT.DecodeNonInterlaced(Stream: TStream; - var ZLIBStream: TZStreamRec2; const Size: Integer; var crcfile: Cardinal); -var - j: Cardinal; - Trans, Data{$IFDEF Store16bits}, Extra{$ENDIF}: pChar; - CopyProc: procedure( - Src, Dest, Trans{$IFDEF Store16bits}, Extra{$ENDIF}: pChar) of object; -begin - CopyProc := nil; {Initialize} - {Determines the method to copy the image data} - case Header.ColorType of - {R, G, B values} - COLOR_RGB: - case Header.BitDepth of - 8: CopyProc := CopyNonInterlacedRGB8; - 16: CopyProc := CopyNonInterlacedRGB16; - end; - {Types using palettes} - COLOR_PALETTE, COLOR_GRAYSCALE: - case Header.BitDepth of - 1, 4, 8: CopyProc := CopyNonInterlacedPalette148; - 2 : if Header.ColorType = COLOR_PALETTE then - CopyProc := CopyNonInterlacedPalette2 - else - CopyProc := CopyNonInterlacedGray2; - 16 : CopyProc := CopyNonInterlacedGrayscale16; - end; - {R, G, B followed by alpha} - COLOR_RGBALPHA: - case Header.BitDepth of - 8 : CopyProc := CopyNonInterlacedRGBAlpha8; - 16 : CopyProc := CopyNonInterlacedRGBAlpha16; - end; - {Grayscale followed by alpha} - COLOR_GRAYSCALEALPHA: - case Header.BitDepth of - 8 : CopyProc := CopyNonInterlacedGrayscaleAlpha8; - 16 : CopyProc := CopyNonInterlacedGrayscaleAlpha16; - end; - end; - - {Get the image data pointer} - Longint(Data) := Longint(Header.ImageData) + - Header.BytesPerRow * (ImageHeight - 1); - Trans := Header.ImageAlpha; - {$IFDEF Store16bits} - Longint(Extra) := Longint(Header.ExtraImageData) + - Header.BytesPerRow * (ImageHeight - 1); - {$ENDIF} - {Reads each line} - FOR j := 0 to ImageHeight - 1 do - begin - {Read this line Row_Buffer[RowUsed][0] if the filter type for this line} - if IDATZlibRead(ZLIBStream, @Row_Buffer[RowUsed][0], Row_Bytes + 1, EndPos, - CRCFile) = 0 then break; - - {Filter the current row} - FilterRow; - {Copies non interlaced row to image} - CopyProc(@Row_Buffer[RowUsed][1], Data, Trans{$IFDEF Store16bits}, Extra - {$ENDIF}); - - {Invert line used} - RowUsed := not RowUsed; - dec(Data, Header.BytesPerRow); - {$IFDEF Store16bits}dec(Extra, Header.BytesPerRow);{$ENDIF} - inc(Trans, ImageWidth); - end {for I}; - - -end; - -{Filter the current line} -procedure TChunkIDAT.FilterRow; -var - pp: Byte; - vv, left, above, aboveleft: Integer; - Col: Cardinal; -begin - {Test the filter} - case Row_Buffer[RowUsed]^[0] of - {No filtering for this line} - FILTER_NONE: begin end; - {AND 255 serves only to never let the result be larger than one byte} - {Sub filter} - FILTER_SUB: - FOR Col := Offset + 1 to Row_Bytes DO - Row_Buffer[RowUsed][Col] := (Row_Buffer[RowUsed][Col] + - Row_Buffer[RowUsed][Col - Offset]) and 255; - {Up filter} - FILTER_UP: - FOR Col := 1 to Row_Bytes DO - Row_Buffer[RowUsed][Col] := (Row_Buffer[RowUsed][Col] + - Row_Buffer[not RowUsed][Col]) and 255; - {Average filter} - FILTER_AVERAGE: - FOR Col := 1 to Row_Bytes DO - begin - {Obtains up and left pixels} - above := Row_Buffer[not RowUsed][Col]; - if col - 1 < Offset then - left := 0 - else - Left := Row_Buffer[RowUsed][Col - Offset]; - - {Calculates} - Row_Buffer[RowUsed][Col] := (Row_Buffer[RowUsed][Col] + - (left + above) div 2) and 255; - end; - {Paeth filter} - FILTER_PAETH: - begin - {Initialize} - left := 0; - aboveleft := 0; - {Test each byte} - FOR Col := 1 to Row_Bytes DO - begin - {Obtains above pixel} - above := Row_Buffer[not RowUsed][Col]; - {Obtains left and top-left pixels} - if (col - 1 >= offset) Then - begin - left := row_buffer[RowUsed][col - offset]; - aboveleft := row_buffer[not RowUsed][col - offset]; - end; - - {Obtains current pixel and paeth predictor} - vv := row_buffer[RowUsed][Col]; - pp := PaethPredictor(left, above, aboveleft); - - {Calculates} - Row_Buffer[RowUsed][Col] := (pp + vv) and $FF; - end {for}; - end; - - end {case}; -end; - -{Reads the image data from the stream} -function TChunkIDAT.LoadFromStream(Stream: TStream; const ChunkName: TChunkName; - Size: Integer): Boolean; -var - ZLIBStream: TZStreamRec2; - CRCCheck, - CRCFile : Cardinal; -begin - {Get pointer to the header chunk} - Header := Owner.Chunks.Item[0] as TChunkIHDR; - {Build palette if necessary} - if Header.HasPalette then PreparePalette(); - - {Copy image width and height} - ImageWidth := Header.Width; - ImageHeight := Header.Height; - - {Initialize to calculate CRC} - {$IFDEF CheckCRC} - CRCFile := update_crc($ffffffff, @ChunkName[0], 4); - {$ENDIF} - - Owner.GetPixelInfo(Row_Bytes, Offset); {Obtain line information} - ZLIBStream := ZLIBInitInflate(Stream); {Initializes decompression} - - {Calculate ending position for the current IDAT chunk} - EndPos := Stream.Position + Size; - - {Allocate memory} - GetMem(Row_Buffer[false], Row_Bytes + 1); - GetMem(Row_Buffer[true], Row_Bytes + 1); - ZeroMemory(Row_Buffer[false], Row_bytes + 1); - {Set the variable to alternate the Row_Buffer item to use} - RowUsed := TRUE; - - {Call special methods for the different interlace methods} - case Owner.InterlaceMethod of - imNone: DecodeNonInterlaced(stream, ZLIBStream, Size, crcfile); - imAdam7: DecodeInterlacedAdam7(stream, ZLIBStream, size, crcfile); - end; - - {Free memory} - ZLIBTerminateInflate(ZLIBStream); {Terminates decompression} - FreeMem(Row_Buffer[False], Row_Bytes + 1); - FreeMem(Row_Buffer[True], Row_Bytes + 1); - - {Now checks CRC} - Stream.Read(CRCCheck, 4); - {$IFDEF CheckCRC} - CRCFile := CRCFile xor $ffffffff; - CRCCheck := ByteSwap(CRCCheck); - Result := CRCCheck = CRCFile; - - {Handle CRC error} - if not Result then - begin - {In case it coult not load chunk} - Owner.RaiseError(EPngInvalidCRC, EPngInvalidCRCText); - exit; - end; - {$ELSE}Result := TRUE; {$ENDIF} -end; - -const - IDATHeader: Array[0..3] of char = ('I', 'D', 'A', 'T'); - BUFFER = 5; - -{Saves the IDAT chunk to a stream} -function TChunkIDAT.SaveToStream(Stream: TStream): Boolean; -var - ZLIBStream : TZStreamRec2; -begin - {Get pointer to the header chunk} - Header := Owner.Chunks.Item[0] as TChunkIHDR; - {Copy image width and height} - ImageWidth := Header.Width; - ImageHeight := Header.Height; - Owner.GetPixelInfo(Row_Bytes, Offset); {Obtain line information} - - {Allocate memory} - GetMem(Encode_Buffer[BUFFER], Row_Bytes); - ZeroMemory(Encode_Buffer[BUFFER], Row_Bytes); - {Allocate buffers for the filters selected} - {Filter none will always be calculated to the other filters to work} - GetMem(Encode_Buffer[FILTER_NONE], Row_Bytes); - ZeroMemory(Encode_Buffer[FILTER_NONE], Row_Bytes); - if pfSub in Owner.Filters then - GetMem(Encode_Buffer[FILTER_SUB], Row_Bytes); - if pfUp in Owner.Filters then - GetMem(Encode_Buffer[FILTER_UP], Row_Bytes); - if pfAverage in Owner.Filters then - GetMem(Encode_Buffer[FILTER_AVERAGE], Row_Bytes); - if pfPaeth in Owner.Filters then - GetMem(Encode_Buffer[FILTER_PAETH], Row_Bytes); - - {Initialize ZLIB} - ZLIBStream := ZLIBInitDeflate(Stream, Owner.fCompressionLevel, - Owner.MaxIdatSize); - {Write data depending on the interlace method} - case Owner.InterlaceMethod of - imNone: EncodeNonInterlaced(stream, ZLIBStream); - imAdam7: EncodeInterlacedAdam7(stream, ZLIBStream); - end; - {Terminates ZLIB} - ZLIBTerminateDeflate(ZLIBStream); - - {Release allocated memory} - FreeMem(Encode_Buffer[BUFFER], Row_Bytes); - FreeMem(Encode_Buffer[FILTER_NONE], Row_Bytes); - if pfSub in Owner.Filters then - FreeMem(Encode_Buffer[FILTER_SUB], Row_Bytes); - if pfUp in Owner.Filters then - FreeMem(Encode_Buffer[FILTER_UP], Row_Bytes); - if pfAverage in Owner.Filters then - FreeMem(Encode_Buffer[FILTER_AVERAGE], Row_Bytes); - if pfPaeth in Owner.Filters then - FreeMem(Encode_Buffer[FILTER_PAETH], Row_Bytes); - - {Everything went ok} - Result := True; -end; - -{Writes the IDAT using the settings} -procedure WriteIDAT(Stream: TStream; Data: Pointer; const Length: Cardinal); -var - ChunkLen, CRC: Cardinal; -begin - {Writes IDAT header} - ChunkLen := ByteSwap(Length); - Stream.Write(ChunkLen, 4); {Chunk length} - Stream.Write(IDATHeader[0], 4); {Idat header} - CRC := update_crc($ffffffff, @IDATHeader[0], 4); {Crc part for header} - - {Writes IDAT data and calculates CRC for data} - Stream.Write(Data^, Length); - CRC := Byteswap(update_crc(CRC, Data, Length) xor $ffffffff); - {Writes final CRC} - Stream.Write(CRC, 4); -end; - -{Compress and writes IDAT chunk data} -procedure TChunkIDAT.IDATZlibWrite(var ZLIBStream: TZStreamRec2; - Buffer: Pointer; const Length: Cardinal); -begin - with ZLIBStream, ZLIBStream.ZLIB do - begin - {Set data to be compressed} - next_in := Buffer; - avail_in := Length; - - {Compress all the data avaliable to compress} - while avail_in > 0 do - begin - deflate(ZLIB, Z_NO_FLUSH); - - {The whole buffer was used, save data to stream and restore buffer} - if avail_out = 0 then - begin - {Writes this IDAT chunk} - WriteIDAT(fStream, Data, ZLIBAllocate); - - {Restore buffer} - next_out := Data; - avail_out := ZLIBAllocate; - end {if avail_out = 0}; - - end {while avail_in}; - - end {with ZLIBStream, ZLIBStream.ZLIB} -end; - -{Finishes compressing data to write IDAT chunk} -procedure TChunkIDAT.FinishIDATZlib(var ZLIBStream: TZStreamRec2); -begin - with ZLIBStream, ZLIBStream.ZLIB do - begin - {Set data to be compressed} - next_in := nil; - avail_in := 0; - - while deflate(ZLIB,Z_FINISH) <> Z_STREAM_END do - begin - {Writes this IDAT chunk} - WriteIDAT(fStream, Data, ZLIBAllocate - avail_out); - {Re-update buffer} - next_out := Data; - avail_out := ZLIBAllocate; - end; - - if avail_out < ZLIBAllocate then - {Writes final IDAT} - WriteIDAT(fStream, Data, ZLIBAllocate - avail_out); - - end {with ZLIBStream, ZLIBStream.ZLIB}; -end; - -{Copy memory to encode RGB image with 1 byte for each color sample} -procedure TChunkIDAT.EncodeNonInterlacedRGB8(Src, Dest, Trans: pChar); -var - I: Integer; -begin - FOR I := 1 TO ImageWidth DO - begin - {Copy pixel values} - Byte(Dest^) := fOwner.InverseGamma[pByte(Longint(Src) + 2)^]; inc(Dest); - Byte(Dest^) := fOwner.InverseGamma[pByte(Longint(Src) + 1)^]; inc(Dest); - Byte(Dest^) := fOwner.InverseGamma[pByte(Longint(Src) )^]; inc(Dest); - {Move to next pixel} - inc(Src, 3); - end {for I} -end; - -{Copy memory to encode RGB images with 16 bits for each color sample} -procedure TChunkIDAT.EncodeNonInterlacedRGB16(Src, Dest, Trans: pChar); -var - I: Integer; -begin - FOR I := 1 TO ImageWidth DO - begin - //Now we copy from 1 byte for each sample stored to a 2 bytes (or 1 word) - //for sample - {Copy pixel values} - pWORD(Dest)^ := fOwner.InverseGamma[pByte(Longint(Src) + 2)^]; inc(Dest, 2); - pWORD(Dest)^ := fOwner.InverseGamma[pByte(Longint(Src) + 1)^]; inc(Dest, 2); - pWORD(Dest)^ := fOwner.InverseGamma[pByte(Longint(Src) )^]; inc(Dest, 2); - {Move to next pixel} - inc(Src, 3); - end {for I} - -end; - -{Copy memory to encode types using palettes (1, 4 or 8 bits per pixel)} -procedure TChunkIDAT.EncodeNonInterlacedPalette148(Src, Dest, Trans: pChar); -begin - {It's simple as copying the data} - CopyMemory(Dest, Src, Row_Bytes); -end; - -{Copy memory to encode grayscale images with 2 bytes for each sample} -procedure TChunkIDAT.EncodeNonInterlacedGrayscale16(Src, Dest, Trans: pChar); -var - I: Integer; -begin - FOR I := 1 TO ImageWidth DO - begin - //Now we copy from 1 byte for each sample stored to a 2 bytes (or 1 word) - //for sample - pWORD(Dest)^ := pByte(Longint(Src))^; inc(Dest, 2); - {Move to next pixel} - inc(Src); - end {for I} -end; - -{Encode images using RGB followed by an alpha value using 1 byte for each} -procedure TChunkIDAT.EncodeNonInterlacedRGBAlpha8(Src, Dest, Trans: pChar); -var - i: Integer; -begin - {Copy the data to the destination, including data from Trans pointer} - FOR i := 1 TO ImageWidth do - begin - Byte(Dest^) := Owner.InverseGamma[PByte(Longint(Src) + 2)^]; inc(Dest); - Byte(Dest^) := Owner.InverseGamma[PByte(Longint(Src) + 1)^]; inc(Dest); - Byte(Dest^) := Owner.InverseGamma[PByte(Longint(Src) )^]; inc(Dest); - Dest^ := Trans^; inc(Dest); - inc(Src, 3); inc(Trans); - end {for i}; -end; - -{Encode images using RGB followed by an alpha value using 2 byte for each} -procedure TChunkIDAT.EncodeNonInterlacedRGBAlpha16(Src, Dest, Trans: pChar); -var - i: Integer; -begin - {Copy the data to the destination, including data from Trans pointer} - FOR i := 1 TO ImageWidth do - begin - pWord(Dest)^ := Owner.InverseGamma[PByte(Longint(Src) + 2)^]; inc(Dest, 2); - pWord(Dest)^ := Owner.InverseGamma[PByte(Longint(Src) + 1)^]; inc(Dest, 2); - pWord(Dest)^ := Owner.InverseGamma[PByte(Longint(Src) )^]; inc(Dest, 2); - pWord(Dest)^ := PByte(Longint(Trans) )^; inc(Dest, 2); - inc(Src, 3); inc(Trans); - end {for i}; -end; - -{Encode grayscale images followed by an alpha value using 1 byte for each} -procedure TChunkIDAT.EncodeNonInterlacedGrayscaleAlpha8( - Src, Dest, Trans: pChar); -var - i: Integer; -begin - {Copy the data to the destination, including data from Trans pointer} - FOR i := 1 TO ImageWidth do - begin - Dest^ := Src^; inc(Dest); - Dest^ := Trans^; inc(Dest); - inc(Src); inc(Trans); - end {for i}; -end; - -{Encode grayscale images followed by an alpha value using 2 byte for each} -procedure TChunkIDAT.EncodeNonInterlacedGrayscaleAlpha16( - Src, Dest, Trans: pChar); -var - i: Integer; -begin - {Copy the data to the destination, including data from Trans pointer} - FOR i := 1 TO ImageWidth do - begin - pWord(Dest)^ := pByte(Src)^; inc(Dest, 2); - pWord(Dest)^ := pByte(Trans)^; inc(Dest, 2); - inc(Src); inc(Trans); - end {for i}; -end; - -{Encode non interlaced images} -procedure TChunkIDAT.EncodeNonInterlaced(Stream: TStream; - var ZLIBStream: TZStreamRec2); -var - {Current line} - j: Cardinal; - {Pointers to image data} - Data, Trans: PChar; - {Filter used for this line} - Filter: Byte; - {Method which will copy the data into the buffer} - CopyProc: procedure(Src, Dest, Trans: pChar) of object; -begin - CopyProc := nil; {Initialize to avoid warnings} - {Defines the method to copy the data to the buffer depending on} - {the image parameters} - case Header.ColorType of - {R, G, B values} - COLOR_RGB: - case Header.BitDepth of - 8: CopyProc := EncodeNonInterlacedRGB8; - 16: CopyProc := EncodeNonInterlacedRGB16; - end; - {Palette and grayscale values} - COLOR_GRAYSCALE, COLOR_PALETTE: - case Header.BitDepth of - 1, 4, 8: CopyProc := EncodeNonInterlacedPalette148; - 16: CopyProc := EncodeNonInterlacedGrayscale16; - end; - {RGB with a following alpha value} - COLOR_RGBALPHA: - case Header.BitDepth of - 8: CopyProc := EncodeNonInterlacedRGBAlpha8; - 16: CopyProc := EncodeNonInterlacedRGBAlpha16; - end; - {Grayscale images followed by an alpha} - COLOR_GRAYSCALEALPHA: - case Header.BitDepth of - 8: CopyProc := EncodeNonInterlacedGrayscaleAlpha8; - 16: CopyProc := EncodeNonInterlacedGrayscaleAlpha16; - end; - end {case Header.ColorType}; - - {Get the image data pointer} - Longint(Data) := Longint(Header.ImageData) + - Header.BytesPerRow * (ImageHeight - 1); - Trans := Header.ImageAlpha; - - {Writes each line} - FOR j := 0 to ImageHeight - 1 do - begin - {Copy data into buffer} - CopyProc(Data, @Encode_Buffer[BUFFER][0], Trans); - {Filter data} - Filter := FilterToEncode; - - {Compress data} - IDATZlibWrite(ZLIBStream, @Filter, 1); - IDATZlibWrite(ZLIBStream, @Encode_Buffer[Filter][0], Row_Bytes); - - {Adjust pointers to the actual image data} - dec(Data, Header.BytesPerRow); - inc(Trans, ImageWidth); - end; - - {Compress and finishes copying the remaining data} - FinishIDATZlib(ZLIBStream); -end; - -{Copy memory to encode interlaced images using RGB value with 1 byte for} -{each color sample} -procedure TChunkIDAT.EncodeInterlacedRGB8(const Pass: Byte; - Src, Dest, Trans: pChar); -var - Col: Integer; -begin - {Get first column and enter in loop} - Col := ColumnStart[Pass]; - Src := pChar(Longint(Src) + Col * 3); - repeat - {Copy this row} - Byte(Dest^) := fOwner.InverseGamma[pByte(Longint(Src) + 2)^]; inc(Dest); - Byte(Dest^) := fOwner.InverseGamma[pByte(Longint(Src) + 1)^]; inc(Dest); - Byte(Dest^) := fOwner.InverseGamma[pByte(Longint(Src) )^]; inc(Dest); - - {Move to next column} - inc(Src, ColumnIncrement[Pass] * 3); - inc(Col, ColumnIncrement[Pass]); - until Col >= ImageWidth; -end; - -{Copy memory to encode interlaced RGB images with 2 bytes each color sample} -procedure TChunkIDAT.EncodeInterlacedRGB16(const Pass: Byte; - Src, Dest, Trans: pChar); -var - Col: Integer; -begin - {Get first column and enter in loop} - Col := ColumnStart[Pass]; - Src := pChar(Longint(Src) + Col * 3); - repeat - {Copy this row} - pWord(Dest)^ := Owner.InverseGamma[pByte(Longint(Src) + 2)^]; inc(Dest, 2); - pWord(Dest)^ := Owner.InverseGamma[pByte(Longint(Src) + 1)^]; inc(Dest, 2); - pWord(Dest)^ := Owner.InverseGamma[pByte(Longint(Src) )^]; inc(Dest, 2); - - {Move to next column} - inc(Src, ColumnIncrement[Pass] * 3); - inc(Col, ColumnIncrement[Pass]); - until Col >= ImageWidth; -end; - -{Copy memory to encode interlaced images using palettes using bit depths} -{1, 4, 8 (each pixel in the image)} -procedure TChunkIDAT.EncodeInterlacedPalette148(const Pass: Byte; - Src, Dest, Trans: pChar); -const - BitTable: Array[1..8] of Integer = ($1, $3, 0, $F, 0, 0, 0, $FF); - StartBit: Array[1..8] of Integer = (7 , 0 , 0, 4, 0, 0, 0, 0); -var - CurBit, Col: Integer; - Src2: PChar; -begin - {Clean the line} - fillchar(Dest^, Row_Bytes, #0); - {Get first column and enter in loop} - Col := ColumnStart[Pass]; - with Header.BitmapInfo.bmiHeader do - repeat - {Copy data} - CurBit := StartBit[biBitCount]; - repeat - {Adjust pointer to pixel byte bounds} - Src2 := pChar(Longint(Src) + (biBitCount * Col) div 8); - {Copy data} - Byte(Dest^) := Byte(Dest^) or - (((Byte(Src2^) shr (StartBit[Header.BitDepth] - (biBitCount * Col) - mod 8))) and (BitTable[biBitCount])) shl CurBit; - - {Move to next column} - inc(Col, ColumnIncrement[Pass]); - {Will read next bits} - dec(CurBit, biBitCount); - until CurBit < 0; - - {Move to next byte in source} - inc(Dest); - until Col >= ImageWidth; -end; - -{Copy to encode interlaced grayscale images using 16 bits for each sample} -procedure TChunkIDAT.EncodeInterlacedGrayscale16(const Pass: Byte; - Src, Dest, Trans: pChar); -var - Col: Integer; -begin - {Get first column and enter in loop} - Col := ColumnStart[Pass]; - Src := pChar(Longint(Src) + Col); - repeat - {Copy this row} - pWord(Dest)^ := Byte(Src^); inc(Dest, 2); - - {Move to next column} - inc(Src, ColumnIncrement[Pass]); - inc(Col, ColumnIncrement[Pass]); - until Col >= ImageWidth; -end; - -{Copy to encode interlaced rgb images followed by an alpha value, all using} -{one byte for each sample} -procedure TChunkIDAT.EncodeInterlacedRGBAlpha8(const Pass: Byte; - Src, Dest, Trans: pChar); -var - Col: Integer; -begin - {Get first column and enter in loop} - Col := ColumnStart[Pass]; - Src := pChar(Longint(Src) + Col * 3); - Trans := pChar(Longint(Trans) + Col); - repeat - {Copy this row} - Byte(Dest^) := Owner.InverseGamma[pByte(Longint(Src) + 2)^]; inc(Dest); - Byte(Dest^) := Owner.InverseGamma[pByte(Longint(Src) + 1)^]; inc(Dest); - Byte(Dest^) := Owner.InverseGamma[pByte(Longint(Src) )^]; inc(Dest); - Dest^ := Trans^; inc(Dest); - - {Move to next column} - inc(Src, ColumnIncrement[Pass] * 3); - inc(Trans, ColumnIncrement[Pass]); - inc(Col, ColumnIncrement[Pass]); - until Col >= ImageWidth; -end; - -{Copy to encode interlaced rgb images followed by an alpha value, all using} -{two byte for each sample} -procedure TChunkIDAT.EncodeInterlacedRGBAlpha16(const Pass: Byte; - Src, Dest, Trans: pChar); -var - Col: Integer; -begin - {Get first column and enter in loop} - Col := ColumnStart[Pass]; - Src := pChar(Longint(Src) + Col * 3); - Trans := pChar(Longint(Trans) + Col); - repeat - {Copy this row} - pWord(Dest)^ := pByte(Longint(Src) + 2)^; inc(Dest, 2); - pWord(Dest)^ := pByte(Longint(Src) + 1)^; inc(Dest, 2); - pWord(Dest)^ := pByte(Longint(Src) )^; inc(Dest, 2); - pWord(Dest)^ := pByte(Trans)^; inc(Dest, 2); - - {Move to next column} - inc(Src, ColumnIncrement[Pass] * 3); - inc(Trans, ColumnIncrement[Pass]); - inc(Col, ColumnIncrement[Pass]); - until Col >= ImageWidth; -end; - -{Copy to encode grayscale interlaced images followed by an alpha value, all} -{using 1 byte for each sample} -procedure TChunkIDAT.EncodeInterlacedGrayscaleAlpha8(const Pass: Byte; - Src, Dest, Trans: pChar); -var - Col: Integer; -begin - {Get first column and enter in loop} - Col := ColumnStart[Pass]; - Src := pChar(Longint(Src) + Col); - Trans := pChar(Longint(Trans) + Col); - repeat - {Copy this row} - Dest^ := Src^; inc(Dest); - Dest^ := Trans^; inc(Dest); - - {Move to next column} - inc(Src, ColumnIncrement[Pass]); - inc(Trans, ColumnIncrement[Pass]); - inc(Col, ColumnIncrement[Pass]); - until Col >= ImageWidth; -end; - -{Copy to encode grayscale interlaced images followed by an alpha value, all} -{using 2 bytes for each sample} -procedure TChunkIDAT.EncodeInterlacedGrayscaleAlpha16(const Pass: Byte; - Src, Dest, Trans: pChar); -var - Col: Integer; -begin - {Get first column and enter in loop} - Col := ColumnStart[Pass]; - Src := pChar(Longint(Src) + Col); - Trans := pChar(Longint(Trans) + Col); - repeat - {Copy this row} - pWord(Dest)^ := pByte(Src)^; inc(Dest, 2); - pWord(Dest)^ := pByte(Trans)^; inc(Dest, 2); - - {Move to next column} - inc(Src, ColumnIncrement[Pass]); - inc(Trans, ColumnIncrement[Pass]); - inc(Col, ColumnIncrement[Pass]); - until Col >= ImageWidth; -end; - -{Encode interlaced images} -procedure TChunkIDAT.EncodeInterlacedAdam7(Stream: TStream; - var ZLIBStream: TZStreamRec2); -var - CurrentPass, Filter: Byte; - PixelsThisRow: Integer; - CurrentRow : Integer; - Trans, Data: pChar; - CopyProc: procedure(const Pass: Byte; - Src, Dest, Trans: pChar) of object; -begin - CopyProc := nil; {Initialize to avoid warnings} - {Defines the method to copy the data to the buffer depending on} - {the image parameters} - case Header.ColorType of - {R, G, B values} - COLOR_RGB: - case Header.BitDepth of - 8: CopyProc := EncodeInterlacedRGB8; - 16: CopyProc := EncodeInterlacedRGB16; - end; - {Grayscale and palette} - COLOR_PALETTE, COLOR_GRAYSCALE: - case Header.BitDepth of - 1, 4, 8: CopyProc := EncodeInterlacedPalette148; - 16: CopyProc := EncodeInterlacedGrayscale16; - end; - {RGB followed by alpha} - COLOR_RGBALPHA: - case Header.BitDepth of - 8: CopyProc := EncodeInterlacedRGBAlpha8; - 16: CopyProc := EncodeInterlacedRGBAlpha16; - end; - COLOR_GRAYSCALEALPHA: - {Grayscale followed by alpha} - case Header.BitDepth of - 8: CopyProc := EncodeInterlacedGrayscaleAlpha8; - 16: CopyProc := EncodeInterlacedGrayscaleAlpha16; - end; - end {case Header.ColorType}; - - {Compress the image using the seven passes for ADAM 7} - FOR CurrentPass := 0 TO 6 DO - begin - {Calculates the number of pixels and bytes for this pass row} - PixelsThisRow := (ImageWidth - ColumnStart[CurrentPass] + - ColumnIncrement[CurrentPass] - 1) div ColumnIncrement[CurrentPass]; - Row_Bytes := BytesForPixels(PixelsThisRow, Header.ColorType, - Header.BitDepth); - ZeroMemory(Encode_Buffer[FILTER_NONE], Row_Bytes); - - {Get current row index} - CurrentRow := RowStart[CurrentPass]; - {Get a pointer to the current row image data} - Data := Ptr(Longint(Header.ImageData) + Header.BytesPerRow * - (ImageHeight - 1 - CurrentRow)); - Trans := Ptr(Longint(Header.ImageAlpha) + ImageWidth * CurrentRow); - - {Process all the image rows} - if Row_Bytes > 0 then - while CurrentRow < ImageHeight do - begin - {Copy data into buffer} - CopyProc(CurrentPass, Data, @Encode_Buffer[BUFFER][0], Trans); - {Filter data} - Filter := FilterToEncode; - - {Compress data} - IDATZlibWrite(ZLIBStream, @Filter, 1); - IDATZlibWrite(ZLIBStream, @Encode_Buffer[Filter][0], Row_Bytes); - - {Move to the next row} - inc(CurrentRow, RowIncrement[CurrentPass]); - {Move pointer to the next line} - dec(Data, RowIncrement[CurrentPass] * Header.BytesPerRow); - inc(Trans, RowIncrement[CurrentPass] * ImageWidth); - end {while CurrentRow < ImageHeight} - - end {CurrentPass}; - - {Compress and finishes copying the remaining data} - FinishIDATZlib(ZLIBStream); -end; - -{Filters the row to be encoded and returns the best filter} -function TChunkIDAT.FilterToEncode: Byte; -var - Run, LongestRun, ii, jj: Cardinal; - Last, Above, LastAbove: Byte; -begin - {Selecting more filters using the Filters property from TPngObject} - {increases the chances to the file be much smaller, but decreases} - {the performace} - - {This method will creates the same line data using the different} - {filter methods and select the best} - - {Sub-filter} - if pfSub in Owner.Filters then - for ii := 0 to Row_Bytes - 1 do - begin - {There is no previous pixel when it's on the first pixel, so} - {set last as zero when in the first} - if (ii >= Offset) then - last := Encode_Buffer[BUFFER]^[ii - Offset] - else - last := 0; - Encode_Buffer[FILTER_SUB]^[ii] := Encode_Buffer[BUFFER]^[ii] - last; - end; - - {Up filter} - if pfUp in Owner.Filters then - for ii := 0 to Row_Bytes - 1 do - Encode_Buffer[FILTER_UP]^[ii] := Encode_Buffer[BUFFER]^[ii] - - Encode_Buffer[FILTER_NONE]^[ii]; - - {Average filter} - if pfAverage in Owner.Filters then - for ii := 0 to Row_Bytes - 1 do - begin - {Get the previous pixel, if the current pixel is the first, the} - {previous is considered to be 0} - if (ii >= Offset) then - last := Encode_Buffer[BUFFER]^[ii - Offset] - else - last := 0; - {Get the pixel above} - above := Encode_Buffer[FILTER_NONE]^[ii]; - - {Calculates formula to the average pixel} - Encode_Buffer[FILTER_AVERAGE]^[ii] := Encode_Buffer[BUFFER]^[ii] - - (above + last) div 2 ; - end; - - {Paeth filter (the slower)} - if pfPaeth in Owner.Filters then - begin - {Initialize} - last := 0; - lastabove := 0; - for ii := 0 to Row_Bytes - 1 do - begin - {In case this pixel is not the first in the line obtains the} - {previous one and the one above the previous} - if (ii >= Offset) then - begin - last := Encode_Buffer[BUFFER]^[ii - Offset]; - lastabove := Encode_Buffer[FILTER_NONE]^[ii - Offset]; - end; - {Obtains the pixel above} - above := Encode_Buffer[FILTER_NONE]^[ii]; - {Calculate paeth filter for this byte} - Encode_Buffer[FILTER_PAETH]^[ii] := Encode_Buffer[BUFFER]^[ii] - - PaethPredictor(last, above, lastabove); - end; - end; - - {Now calculates the same line using no filter, which is necessary} - {in order to have data to the filters when the next line comes} - CopyMemory(@Encode_Buffer[FILTER_NONE]^[0], - @Encode_Buffer[BUFFER]^[0], Row_Bytes); - - {If only filter none is selected in the filter list, we don't need} - {to proceed and further} - if (Owner.Filters = [pfNone]) or (Owner.Filters = []) then - begin - Result := FILTER_NONE; - exit; - end {if (Owner.Filters = [pfNone...}; - - {Check which filter is the best by checking which has the larger} - {sequence of the same byte, since they are best compressed} - LongestRun := 0; Result := FILTER_NONE; - for ii := FILTER_NONE TO FILTER_PAETH do - {Check if this filter was selected} - if TFilter(ii) in Owner.Filters then - begin - Run := 0; - {Check if it's the only filter} - if Owner.Filters = [TFilter(ii)] then - begin - Result := ii; - exit; - end; - - {Check using a sequence of four bytes} - for jj := 2 to Row_Bytes - 1 do - if (Encode_Buffer[ii]^[jj] = Encode_Buffer [ii]^[jj-1]) or - (Encode_Buffer[ii]^[jj] = Encode_Buffer [ii]^[jj-2]) then - inc(Run); {Count the number of sequences} - - {Check if this one is the best so far} - if (Run > LongestRun) then - begin - Result := ii; - LongestRun := Run; - end {if (Run > LongestRun)}; - - end {if TFilter(ii) in Owner.Filters}; -end; - -{TChunkPLTE implementation} - -{Returns an item in the palette} -function TChunkPLTE.GetPaletteItem(Index: Byte): TRGBQuad; -begin - {Test if item is valid, if not raise error} - if Index > Count - 1 then - Owner.RaiseError(EPNGError, EPNGUnknownPalEntryText) - else - {Returns the item} - Result := Header.BitmapInfo.bmiColors[Index]; -end; - -{Loads the palette chunk from a stream} -function TChunkPLTE.LoadFromStream(Stream: TStream; - const ChunkName: TChunkName; Size: Integer): Boolean; -type - pPalEntry = ^PalEntry; - PalEntry = record r, g, b: Byte end; -var - j : Integer; {For the FOR} - PalColor : pPalEntry; -begin - {Let ancestor load data and check CRC} - Result := inherited LoadFromStream(Stream, ChunkName, Size); - if not Result then exit; - - {This chunk must be divisible by 3 in order to be valid} - if (Size mod 3 <> 0) or (Size div 3 > 256) then - begin - {Raise error} - Result := FALSE; - Owner.RaiseError(EPNGInvalidPalette, EPNGInvalidPaletteText); - exit; - end {if Size mod 3 <> 0}; - - {Fill array with the palette entries} - fCount := Size div 3; - PalColor := Data; - FOR j := 0 TO fCount - 1 DO - with Header.BitmapInfo.bmiColors[j] do - begin - rgbRed := Owner.GammaTable[PalColor.r]; - rgbGreen := Owner.GammaTable[PalColor.g]; - rgbBlue := Owner.GammaTable[PalColor.b]; - rgbReserved := 0; - inc(PalColor); {Move to next palette entry} - end; -end; - -{Saves the PLTE chunk to a stream} -function TChunkPLTE.SaveToStream(Stream: TStream): Boolean; -var - J: Integer; - DataPtr: pByte; -begin - {Adjust size to hold all the palette items} - ResizeData(fCount * 3); - {Copy pointer to data} - DataPtr := fData; - - {Copy palette items} - with Header do - FOR j := 0 TO fCount - 1 DO - with BitmapInfo.bmiColors[j] do - begin - DataPtr^ := Owner.InverseGamma[rgbRed]; inc(DataPtr); - DataPtr^ := Owner.InverseGamma[rgbGreen]; inc(DataPtr); - DataPtr^ := Owner.InverseGamma[rgbBlue]; inc(DataPtr); - end {with BitmapInfo}; - - {Let ancestor do the rest of the work} - Result := inherited SaveToStream(Stream); -end; - -{Assigns from another PLTE chunk} -procedure TChunkPLTE.Assign(Source: TChunk); -begin - {Copy the number of palette items} - if Source is TChunkPLTE then - fCount := TChunkPLTE(Source).fCount - else - Owner.RaiseError(EPNGError, EPNGCannotAssignChunkText); -end; - -{TChunkgAMA implementation} - -{Assigns from another chunk} -procedure TChunkgAMA.Assign(Source: TChunk); -begin - {Copy the gamma value} - if Source is TChunkgAMA then - Gamma := TChunkgAMA(Source).Gamma - else - Owner.RaiseError(EPNGError, EPNGCannotAssignChunkText); -end; - -{Gamma chunk being created} -constructor TChunkgAMA.Create(Owner: TPngObject); -begin - {Call ancestor} - inherited Create(Owner); - Gamma := 1; {Initial value} -end; - -{Returns gamma value} -function TChunkgAMA.GetValue: Cardinal; -begin - {Make sure that the size is four bytes} - if DataSize <> 4 then - begin - {Adjust size and returns 1} - ResizeData(4); - Result := 1; - end - {If it's right, read the value} - else Result := Cardinal(ByteSwap(pCardinal(Data)^)) -end; - -function Power(Base, Exponent: Extended): Extended; -begin - if Exponent = 0.0 then - Result := 1.0 {Math rule} - else if (Base = 0) or (Exponent = 0) then Result := 0 - else - Result := Exp(Exponent * Ln(Base)); -end; - - -{Loading the chunk from a stream} -function TChunkgAMA.LoadFromStream(Stream: TStream; - const ChunkName: TChunkName; Size: Integer): Boolean; -var - i: Integer; - Value: Cardinal; -begin - {Call ancestor and test if it went ok} - Result := inherited LoadFromStream(Stream, ChunkName, Size); - if not Result then exit; - Value := Gamma; - {Build gamma table and inverse table for saving} - if Value <> 0 then - with Owner do - FOR i := 0 TO 255 DO - begin - GammaTable[I] := Round(Power((I / 255), 1 / - (Value / 100000 * 2.2)) * 255); - InverseGamma[Round(Power((I / 255), 1 / - (Value / 100000 * 2.2)) * 255)] := I; - end -end; - -{Sets the gamma value} -procedure TChunkgAMA.SetValue(const Value: Cardinal); -begin - {Make sure that the size is four bytes} - if DataSize <> 4 then ResizeData(4); - {If it's right, set the value} - pCardinal(Data)^ := ByteSwap(Value); -end; - -{TPngObject implementation} - -{Assigns from another object} -procedure TPngObject.Assign(Source: TPersistent); -begin - {Assigns contents from another TPNGObject} - if Source is TPNGObject then - AssignPNG(Source as TPNGObject) - {Copy contents from a TBitmap} - {$IFDEF UseDelphi}else if Source is TBitmap then - with Source as TBitmap do - AssignHandle(Handle, Transparent, - ColorToRGB(TransparentColor)){$ENDIF} - {Unknown source, let ancestor deal with it} - else - inherited; -end; - -{Clear all the chunks in the list} -procedure TPngObject.ClearChunks; -var - i: Integer; -begin - {Initialize gamma} - InitializeGamma(); - {Free all the objects and memory (0 chunks Bug fixed by Noel Sharpe)} - for i := 0 TO Integer(Chunks.Count) - 1 do - TChunk(Chunks.Item[i]).Free; - Chunks.Count := 0; -end; - -{Portable Network Graphics object being created} -constructor TPngObject.Create; -begin - {Let it be created} - inherited Create; - - {Initial properties} - TempPalette := 0; - fFilters := [pfSub]; - fCompressionLevel := 7; - fInterlaceMethod := imNone; - fMaxIdatSize := High(Word); - {Create chunklist object} - fChunkList := TPngList.Create(Self); -end; - -{Portable Network Graphics object being destroyed} -destructor TPngObject.Destroy; -begin - {Free object list} - ClearChunks; - fChunkList.Free; - {Free the temporary palette} - if TempPalette <> 0 then DeleteObject(TempPalette); - - {Call ancestor destroy} - inherited Destroy; -end; - -{Returns linesize and byte offset for pixels} -procedure TPngObject.GetPixelInfo(var LineSize, Offset: Cardinal); -begin - {There must be an Header chunk to calculate size} - if HeaderPresent then - begin - {Calculate number of bytes for each line} - LineSize := BytesForPixels(Header.Width, Header.ColorType, Header.BitDepth); - - {Calculates byte offset} - Case Header.ColorType of - {Grayscale} - COLOR_GRAYSCALE: - If Header.BitDepth = 16 Then - Offset := 2 - Else - Offset := 1 ; - {It always smaller or equal one byte, so it occupes one byte} - COLOR_PALETTE: - offset := 1; - {It might be 3 or 6 bytes} - COLOR_RGB: - offset := 3 * Header.BitDepth Div 8; - {It might be 2 or 4 bytes} - COLOR_GRAYSCALEALPHA: - offset := 2 * Header.BitDepth Div 8; - {4 or 8 bytes} - COLOR_RGBALPHA: - offset := 4 * Header.BitDepth Div 8; - else - Offset := 0; - End ; - - end - else - begin - {In case if there isn't any Header chunk} - Offset := 0; - LineSize := 0; - end; - -end; - -{Returns image height} -function TPngObject.GetHeight: Integer; -begin - {There must be a Header chunk to get the size, otherwise returns 0} - if HeaderPresent then - Result := TChunkIHDR(Chunks.Item[0]).Height - else Result := 0; -end; - -{Returns image width} -function TPngObject.GetWidth: Integer; -begin - {There must be a Header chunk to get the size, otherwise returns 0} - if HeaderPresent then - Result := Header.Width - else Result := 0; -end; - -{Returns if the image is empty} -function TPngObject.GetEmpty: Boolean; -begin - Result := (Chunks.Count = 0); -end; - -{Raises an error} -procedure TPngObject.RaiseError(ExceptionClass: ExceptClass; Text: String); -begin - raise ExceptionClass.Create(Text); -end; - -{Set the maximum size for IDAT chunk} -procedure TPngObject.SetMaxIdatSize(const Value: Cardinal); -begin - {Make sure the size is at least 65535} - if Value < High(Word) then - fMaxIdatSize := High(Word) else fMaxIdatSize := Value; -end; - -{$IFNDEF UseDelphi} - {Creates a file stream reading from the filename in the parameter and load} - procedure TPngObject.LoadFromFile(const Filename: String); - var - FileStream: TFileStream; - begin - {Test if the file exists} - if not FileExists(Filename) then - begin - {In case it does not exists, raise error} - RaiseError(EPNGNotExists, EPNGNotExistsText); - exit; - end; - - {Creates the file stream to read} - FileStream := TFileStream.Create(Filename, [fsmRead]); - LoadFromStream(FileStream); {Loads the data} - FileStream.Free; {Free file stream} - end; - - {Saves the current png image to a file} - procedure TPngObject.SaveToFile(const Filename: String); - var - FileStream: TFileStream; - begin - {Creates the file stream to write} - FileStream := TFileStream.Create(Filename, [fsmWrite]); - SaveToStream(FileStream); {Saves the data} - FileStream.Free; {Free file stream} - end; - -{$ENDIF} - -{Returns pointer to the chunk TChunkIHDR which should be the first} -function TPngObject.GetHeader: TChunkIHDR; -begin - {If there is a TChunkIHDR returns it, otherwise returns nil} - if (Chunks.Count <> 0) and (Chunks.Item[0] is TChunkIHDR) then - Result := Chunks.Item[0] as TChunkIHDR - else - begin - {No header, throw error message} - RaiseError(EPNGHeaderNotPresent, EPNGHeaderNotPresentText); - Result := nil - end -end; - -{Draws using partial transparency} -procedure TPngObject.DrawPartialTrans(DC: HDC; Rect: TRect); -type - {Access to pixels} - TPixelLine = Array[Word] of TRGBQuad; - pPixelLine = ^TPixelLine; -const - {Structure used to create the bitmap} - BitmapInfoHeader: TBitmapInfoHeader = - (biSize: sizeof(TBitmapInfoHeader); - biWidth: 100; - biHeight: 100; - biPlanes: 1; - biBitCount: 32; - biCompression: BI_RGB; - biSizeImage: 0; - biXPelsPerMeter: 0; - biYPelsPerMeter: 0; - biClrUsed: 0; - biClrImportant: 0); -var - {Buffer bitmap creation} - BitmapInfo : TBitmapInfo; - BufferDC : HDC; - BufferBits : Pointer; - OldBitmap, - BufferBitmap: HBitmap; - - {Transparency/palette chunks} - TransparencyChunk: TChunktRNS; - PaletteChunk: TChunkPLTE; - TransValue, PaletteIndex: Byte; - CurBit: Integer; - Data: PByte; - - {Buffer bitmap modification} - BytesPerRowDest, - BytesPerRowSrc, - BytesPerRowAlpha: Integer; - ImageSource, - AlphaSource : pByteArray; - ImageData : pPixelLine; - i, j : Integer; -begin - {Prepare to create the bitmap} - Fillchar(BitmapInfo, sizeof(BitmapInfo), #0); - BitmapInfoHeader.biWidth := Header.Width; - BitmapInfoHeader.biHeight := -1 * Header.Height; - BitmapInfo.bmiHeader := BitmapInfoHeader; - - {Create the bitmap which will receive the background, the applied} - {alpha blending and then will be painted on the background} - BufferDC := CreateCompatibleDC(0); - {In case BufferDC could not be created} - if (BufferDC = 0) then RaiseError(EPNGOutMemory, EPNGOutMemoryText); - BufferBitmap := CreateDIBSection(BufferDC, BitmapInfo, DIB_RGB_COLORS, - BufferBits, 0, 0); - {In case buffer bitmap could not be created} - if (BufferBitmap = 0) or (BufferBits = Nil) then - begin - if BufferBitmap <> 0 then DeleteObject(BufferBitmap); - DeleteDC(BufferDC); - RaiseError(EPNGOutMemory, EPNGOutMemoryText); - end; - - {Selects new bitmap and release old bitmap} - OldBitmap := SelectObject(BufferDC, BufferBitmap); - - {Draws the background on the buffer image} - StretchBlt(BufferDC, 0, 0, Header.Width, Header.height, DC, Rect.Left, - Rect.Top, Header.Width, Header.Height, SRCCOPY); - - {Obtain number of bytes for each row} - BytesPerRowAlpha := Header.Width; - BytesPerRowDest := (((BitmapInfo.bmiHeader.biBitCount * Width) + 31) - and not 31) div 8; {Number of bytes for each image row in destination} - BytesPerRowSrc := (((Header.BitmapInfo.bmiHeader.biBitCount * Header.Width) + - 31) and not 31) div 8; {Number of bytes for each image row in source} - - {Obtains image pointers} - ImageData := BufferBits; - AlphaSource := Header.ImageAlpha; - Longint(ImageSource) := Longint(Header.ImageData) + - Header.BytesPerRow * Longint(Header.Height - 1); - - case Header.BitmapInfo.bmiHeader.biBitCount of - {R, G, B images} - 24: - FOR j := 1 TO Header.Height DO - begin - {Process all the pixels in this line} - FOR i := 0 TO Header.Width - 1 DO - with ImageData[i] do - begin - rgbRed := (255+ImageSource[2+i*3] * AlphaSource[i] + rgbRed * (255 - - AlphaSource[i])) shr 8; - rgbGreen := (255+ImageSource[1+i*3] * AlphaSource[i] + rgbGreen * - (255 - AlphaSource[i])) shr 8; - rgbBlue := (255+ImageSource[i*3] * AlphaSource[i] + rgbBlue * - (255 - AlphaSource[i])) shr 8; - end; - - {Move pointers} - Longint(ImageData) := Longint(ImageData) + BytesPerRowDest; - Longint(ImageSource) := Longint(ImageSource) - BytesPerRowSrc; - Longint(AlphaSource) := Longint(AlphaSource) + BytesPerRowAlpha; - end; - {Palette images with 1 byte for each pixel} - 1,4,8: if Header.ColorType = COLOR_GRAYSCALEALPHA then - FOR j := 1 TO Header.Height DO - begin - {Process all the pixels in this line} - FOR i := 0 TO Header.Width - 1 DO - with ImageData[i], Header.BitmapInfo do begin - rgbRed := (255 + ImageSource[i] * AlphaSource[i] + - rgbRed * (255 - AlphaSource[i])) shr 8; - rgbGreen := (255 + ImageSource[i] * AlphaSource[i] + - rgbGreen * (255 - AlphaSource[i])) shr 8; - rgbBlue := (255 + ImageSource[i] * AlphaSource[i] + - rgbBlue * (255 - AlphaSource[i])) shr 8; - end; - - {Move pointers} - Longint(ImageData) := Longint(ImageData) + BytesPerRowDest; - Longint(ImageSource) := Longint(ImageSource) - BytesPerRowSrc; - Longint(AlphaSource) := Longint(AlphaSource) + BytesPerRowAlpha; - end - else {Palette images} - begin - {Obtain pointer to the transparency chunk} - TransparencyChunk := TChunktRNS(Chunks.ItemFromClass(TChunktRNS)); - PaletteChunk := TChunkPLTE(Chunks.ItemFromClass(TChunkPLTE)); - - FOR j := 1 TO Header.Height DO - begin - {Process all the pixels in this line} - i := 0; Data := @ImageSource[0]; - repeat - CurBit := 0; - - repeat - {Obtains the palette index} - case Header.BitDepth of - 1: PaletteIndex := (Data^ shr (7-(I Mod 8))) and 1; - 2,4: PaletteIndex := (Data^ shr ((1-(I Mod 2))*4)) and $0F; - else PaletteIndex := Data^; - end; - - {Updates the image with the new pixel} - with ImageData[i] do - begin - TransValue := TransparencyChunk.PaletteValues[PaletteIndex]; - rgbRed := (255 + PaletteChunk.Item[PaletteIndex].rgbRed * - TransValue + rgbRed * (255 - TransValue)) shr 8; - rgbGreen := (255 + PaletteChunk.Item[PaletteIndex].rgbGreen * - TransValue + rgbGreen * (255 - TransValue)) shr 8; - rgbBlue := (255 + PaletteChunk.Item[PaletteIndex].rgbBlue * - TransValue + rgbBlue * (255 - TransValue)) shr 8; - end; - - {Move to next data} - inc(i); inc(CurBit, Header.BitmapInfo.bmiHeader.biBitCount); - until CurBit >= 8; - {Move to next source data} - inc(Data); - until i >= Integer(Header.Width); - - {Move pointers} - Longint(ImageData) := Longint(ImageData) + BytesPerRowDest; - Longint(ImageSource) := Longint(ImageSource) - BytesPerRowSrc; - end - end {Palette images} - end {case Header.BitmapInfo.bmiHeader.biBitCount}; - - {Draws the new bitmap on the foreground} - StretchBlt(DC, Rect.Left, Rect.Top, Header.Width, Header.Height, BufferDC, - 0, 0, Header.Width, Header.Height, SRCCOPY); - - {Free bitmap} - SelectObject(BufferDC, OldBitmap); - DeleteObject(BufferBitmap); - DeleteDC(BufferDC); -end; - -{Draws the image into a canvas} -procedure TPngObject.Draw(ACanvas: TCanvas; const Rect: TRect); -var - Header: TChunkIHDR; -begin - {Quit in case there is no header, otherwise obtain it} - if (Chunks.Count = 0) or not (Chunks.GetItem(0) is TChunkIHDR) then Exit; - Header := Chunks.GetItem(0) as TChunkIHDR; - - {Copy the data to the canvas} - case Self.TransparencyMode of - {$IFDEF PartialTransparentDraw} - ptmPartial: - DrawPartialTrans(ACanvas{$IFDEF UseDelphi}.Handle{$ENDIF}, Rect); - {$ENDIF} - ptmBit: DrawTransparentBitmap(ACanvas{$IFDEF UseDelphi}.Handle{$ENDIF}, - Header.ImageData, Header.BitmapInfo.bmiHeader, - pBitmapInfo(@Header.BitmapInfo), Rect, - {$IFDEF UseDelphi}ColorToRGB({$ENDIF}TransparentColor) - {$IFDEF UseDelphi}){$ENDIF} - else - StretchDiBits(ACanvas{$IFDEF UseDelphi}.Handle{$ENDIF}, Rect.Left, - Rect.Top, Rect.Right - Rect.Left, Rect.Bottom - Rect.Top, 0, 0, - Header.Width, Header.Height, Header.ImageData, - pBitmapInfo(@Header.BitmapInfo)^, DIB_RGB_COLORS, SRCCOPY) - end {case} -end; - -{Characters for the header} -const - PngHeader: Array[0..7] of Char = (#137, #80, #78, #71, #13, #10, #26, #10); - -{Loads the image from a stream of data} -procedure TPngObject.LoadFromStream(Stream: TStream); -var - Header : Array[0..7] of Char; - HasIDAT : Boolean; - - {Chunks reading} - ChunkCount : Cardinal; - ChunkLength: Cardinal; - ChunkName : TChunkName; -begin - {Initialize before start loading chunks} - ChunkCount := 0; - ClearChunks(); - {Reads the header} - Stream.Read(Header[0], 8); - - {Test if the header matches} - if Header <> PngHeader then - begin - RaiseError(EPNGInvalidFileHeader, EPNGInvalidFileHeaderText); - Exit; - end; - - - HasIDAT := FALSE; - Chunks.Count := 10; - - {Load chunks} - repeat - inc(ChunkCount); {Increment number of chunks} - if Chunks.Count < ChunkCount then {Resize the chunks list if needed} - Chunks.Count := Chunks.Count + 10; - - {Reads chunk length and invert since it is in network order} - {also checks the Read method return, if it returns 0, it} - {means that no bytes was readed, probably because it reached} - {the end of the file} - if Stream.Read(ChunkLength, 4) = 0 then - begin - {In case it found the end of the file here} - Chunks.Count := ChunkCount - 1; - RaiseError(EPNGUnexpectedEnd, EPNGUnexpectedEndText); - end; - - ChunkLength := ByteSwap(ChunkLength); - {Reads chunk name} - Stream.Read(Chunkname, 4); - - {Here we check if the first chunk is the Header which is necessary} - {to the file in order to be a valid Portable Network Graphics image} - if (ChunkCount = 1) and (ChunkName <> 'IHDR') then - begin - Chunks.Count := ChunkCount - 1; - RaiseError(EPNGIHDRNotFirst, EPNGIHDRNotFirstText); - exit; - end; - - {Has a previous IDAT} - if (HasIDAT and (ChunkName = 'IDAT')) or (ChunkName = 'cHRM') then - begin - dec(ChunkCount); - Stream.Seek(ChunkLength + 4, soFromCurrent); - Continue; - end; - {Tell it has an IDAT chunk} - if ChunkName = 'IDAT' then HasIDAT := TRUE; - - {Creates object for this chunk} - Chunks.SetItem(ChunkCount - 1, CreateClassChunk(Self, ChunkName)); - - {Check if the chunk is critical and unknown} - {$IFDEF ErrorOnUnknownCritical} - if (TChunk(Chunks.Item[ChunkCount - 1]).ClassType = TChunk) and - ((Byte(ChunkName[0]) AND $20) = 0) and (ChunkName <> '') then - begin - Chunks.Count := ChunkCount; - RaiseError(EPNGUnknownCriticalChunk, EPNGUnknownCriticalChunkText); - end; - {$ENDIF} - - {Loads it} - try if not TChunk(Chunks.Item[ChunkCount - 1]).LoadFromStream(Stream, - ChunkName, ChunkLength) then break; - except - Chunks.Count := ChunkCount; - raise; - end; - - {Terminates when it reaches the IEND chunk} - until (ChunkName = 'IEND'); - - {Resize the list to the appropriate size} - Chunks.Count := ChunkCount; - - {Check if there is data} - if not HasIDAT then - RaiseError(EPNGNoImageData, EPNGNoImageDataText); -end; - -{Changing height is not supported} -procedure TPngObject.SetHeight(Value: Integer); -begin - RaiseError(EPNGError, EPNGCannotChangeSizeText); -end; - -{Changing width is not supported} -procedure TPngObject.SetWidth(Value: Integer); -begin - RaiseError(EPNGError, EPNGCannotChangeSizeText); -end; - -{$IFDEF UseDelphi} -{Saves to clipboard format (thanks to Antoine Pottern)} -procedure TPNGObject.SaveToClipboardFormat(var AFormat: Word; - var AData: THandle; var APalette: HPalette); -begin - with TBitmap.Create do - try - Width := Self.Width; - Height := Self.Height; - Self.Draw(Canvas, Rect(0, 0, Width, Height)); - SaveToClipboardFormat(AFormat, AData, APalette); - finally - Free; - end {try} -end; - -{Loads data from clipboard} -procedure TPngObject.LoadFromClipboardFormat(AFormat: Word; - AData: THandle; APalette: HPalette); -begin - with TBitmap.Create do - try - LoadFromClipboardFormat(AFormat, AData, APalette); - Self.AssignHandle(Handle, False, 0); - finally - Free; - end {try} -end; - -{Returns if the image is transparent} -function TPngObject.GetTransparent: Boolean; -begin - Result := (TransparencyMode <> ptmNone); -end; - -{$ENDIF} - -{Saving the PNG image to a stream of data} -procedure TPngObject.SaveToStream(Stream: TStream); -var - j: Integer; -begin - {Reads the header} - Stream.Write(PNGHeader[0], 8); - {Write each chunk} - FOR j := 0 TO Chunks.Count - 1 DO - Chunks.Item[j].SaveToStream(Stream) -end; - -{Prepares the Header chunk} -procedure BuildHeader(Header: TChunkIHDR; Handle: HBitmap; Info: pBitmap; - HasPalette: Boolean); -var - DC: HDC; -begin - {Set width and height} - Header.Width := Info.bmWidth; - Header.Height := abs(Info.bmHeight); - {Set bit depth} - if Info.bmBitsPixel >= 16 then - Header.BitDepth := 8 else Header.BitDepth := Info.bmBitsPixel; - {Set color type} - if Info.bmBitsPixel >= 16 then - Header.ColorType := COLOR_RGB else Header.ColorType := COLOR_PALETTE; - {Set other info} - Header.CompressionMethod := 0; {deflate/inflate} - Header.InterlaceMethod := 0; {no interlace} - - {Prepares bitmap headers to hold data} - Header.PrepareImageData(); - {Copy image data} - DC := CreateCompatibleDC(0); - GetDIBits(DC, Handle, 0, Header.Height, Header.ImageData, - pBitmapInfo(@Header.BitmapInfo)^, DIB_RGB_COLORS); - DeleteDC(DC); -end; - -{Loads the image from a resource} -procedure TPngObject.LoadFromResourceName(Instance: HInst; - const Name: String); -var - ResStream: TResourceStream; -begin - {Creates an especial stream to load from the resource} - try ResStream := TResourceStream.Create(Instance, Name, RT_RCDATA); - except RaiseError(EPNGCouldNotLoadResource, EPNGCouldNotLoadResourceText); - exit; end; - - {Loads the png image from the resource} - try - LoadFromStream(ResStream); - finally - ResStream.Free; - end; -end; - -{Loads the png from a resource ID} -procedure TPngObject.LoadFromResourceID(Instance: HInst; ResID: Integer); -begin - LoadFromResourceName(Instance, String(ResID)); -end; - -{Assigns this tpngobject to another object} -procedure TPngObject.AssignTo(Dest: TPersistent); -{$IFDEF UseDelphi} -var - DeskDC: HDC; - TRNS: TChunkTRNS; -{$ENDIF} -begin - {If the destination is also a TPNGObject make it assign} - {this one} - if Dest is TPNGObject then - TPNGObject(Dest).AssignPNG(Self) - {$IFDEF UseDelphi} - {In case the destination is a bitmap} - else if (Dest is TBitmap) and HeaderPresent then - begin - {Device context} - DeskDC := GetDC(0); - {Copy the data} - TBitmap(Dest).Handle := CreateDIBitmap(DeskDC, - Header.BitmapInfo.bmiHeader, CBM_INIT, Header.ImageData, - pBitmapInfo(@Header.BitmapInfo)^, DIB_RGB_COLORS); - ReleaseDC(0, DeskDC); - {Tests for the best pixelformat} - case Header.BitmapInfo.bmiHeader.biBitCount of - 1: TBitmap(Dest).PixelFormat := pf1Bit; - 4: TBitmap(Dest).PixelFormat := pf4Bit; - 8: TBitmap(Dest).PixelFormat := pf8Bit; - 24: TBitmap(Dest).PixelFormat := pf24Bit; - 32: TBitmap(Dest).PixelFormat := pf32Bit; - end {case Header.BitmapInfo.bmiHeader.biBitCount}; - - {Copy transparency mode} - if (TransparencyMode = ptmBit) then - begin - TRNS := Chunks.ItemFromClass(TChunkTRNS) as TChunkTRNS; - TBitmap(Dest).TransparentColor := TRNS.TransparentColor; - TBitmap(Dest).Transparent := True - end {if (TransparencyMode = ptmBit)} - - end - else - {Unknown destination kind, } - inherited AssignTo(Dest); - {$ENDIF} -end; - -{Assigns from a bitmap object} -procedure TPngObject.AssignHandle(Handle: HBitmap; Transparent: Boolean; - TransparentColor: ColorRef); -var - BitmapInfo: Windows.TBitmap; - HasPalette: Boolean; - - {Chunks} - Header: TChunkIHDR; - PLTE: TChunkPLTE; - IDAT: TChunkIDAT; - IEND: TChunkIEND; - TRNS: TChunkTRNS; -begin - {Obtain bitmap info} - GetObject(Handle, SizeOf(BitmapInfo), @BitmapInfo); - - {Only bit depths 1, 4 and 8 needs a palette} - HasPalette := (BitmapInfo.bmBitsPixel < 16); - - {Clear old chunks and prepare} - ClearChunks(); - - {Create the chunks} - Header := TChunkIHDR.Create(Self); - if HasPalette then PLTE := TChunkPLTE.Create(Self) else PLTE := nil; - if Transparent then TRNS := TChunkTRNS.Create(Self) else TRNS := nil; - IDAT := TChunkIDAT.Create(Self); - IEND := TChunkIEND.Create(Self); - - {Add chunks} - TPNGPointerList(Chunks).Add(Header); - if HasPalette then TPNGPointerList(Chunks).Add(PLTE); - if Transparent then TPNGPointerList(Chunks).Add(TRNS); - TPNGPointerList(Chunks).Add(IDAT); - TPNGPointerList(Chunks).Add(IEND); - - {This method will fill the Header chunk with bitmap information} - {and copy the image data} - BuildHeader(Header, Handle, @BitmapInfo, HasPalette); - {In case there is a image data, set the PLTE chunk fCount variable} - {to the actual number of palette colors which is 2^(Bits for each pixel)} - if HasPalette then PLTE.fCount := 1 shl BitmapInfo.bmBitsPixel; - - {In case it is a transparent bitmap, prepares it} - if Transparent then TRNS.TransparentColor := TransparentColor; - -end; - -{Assigns from another PNG} -procedure TPngObject.AssignPNG(Source: TPNGObject); -var - J: Integer; -begin - {Copy properties} - InterlaceMethod := Source.InterlaceMethod; - MaxIdatSize := Source.MaxIdatSize; - CompressionLevel := Source.CompressionLevel; - Filters := Source.Filters; - - {Clear old chunks and prepare} - ClearChunks(); - Chunks.Count := Source.Chunks.Count; - {Create chunks and makes a copy from the source} - FOR J := 0 TO Chunks.Count - 1 DO - with Source.Chunks do - begin - Chunks.SetItem(J, TChunkClass(TChunk(Item[J]).ClassType).Create(Self)); - TChunk(Chunks.Item[J]).Assign(TChunk(Item[J])); - end {with}; -end; - -{Returns a alpha data scanline} -function TPngObject.GetAlphaScanline(const LineIndex: Integer): pByteArray; -begin - with Header do - if (ColorType = COLOR_RGBALPHA) or (ColorType = COLOR_GRAYSCALEALPHA) then - Longint(Result) := Longint(ImageAlpha) + (LineIndex * Longint(Width)) - else Result := nil; {In case the image does not use alpha information} -end; - -{$IFDEF Store16bits} -{Returns a png data extra scanline} -function TPngObject.GetExtraScanline(const LineIndex: Integer): Pointer; -begin - with Header do - Longint(Result) := (Longint(ExtraImageData) + ((Longint(Height) - 1) * - BytesPerRow)) - (LineIndex * BytesPerRow); -end; -{$ENDIF} - -{Returns a png data scanline} -function TPngObject.GetScanline(const LineIndex: Integer): Pointer; -begin - with Header do - Longint(Result) := (Longint(ImageData) + ((Longint(Height) - 1) * - BytesPerRow)) - (LineIndex * BytesPerRow); -end; - -{Initialize gamma table} -procedure TPngObject.InitializeGamma; -var - i: Integer; -begin - {Build gamma table as if there was no gamma} - FOR i := 0 to 255 do - begin - GammaTable[i] := i; - InverseGamma[i] := i; - end {for i} -end; - -{Returns the transparency mode used by this png} -function TPngObject.GetTransparencyMode: TPNGTransparencyMode; -var - TRNS: TChunkTRNS; -begin - with Header do - begin - Result := ptmNone; {Default result} - {Gets the TRNS chunk pointer} - TRNS := Chunks.ItemFromClass(TChunkTRNS) as TChunkTRNS; - - {Test depending on the color type} - case ColorType of - {This modes are always partial} - COLOR_RGBALPHA, COLOR_GRAYSCALEALPHA: Result := ptmPartial; - {This modes support bit transparency} - COLOR_RGB, COLOR_GRAYSCALE: if TRNS <> nil then Result := ptmBit; - {Supports booth translucid and bit} - COLOR_PALETTE: - {A TRNS chunk must be present, otherwise it won't support transparency} - if TRNS <> nil then - if TRNS.BitTransparency then - Result := ptmBit else Result := ptmPartial - end {case} - - end {with Header} -end; - -{Add a text chunk} -procedure TPngObject.AddtEXt(const Keyword, Text: String); -var - TextChunk: TChunkTEXT; -begin - TextChunk := Chunks.Add(TChunkText) as TChunkTEXT; - TextChunk.Keyword := Keyword; - TextChunk.Text := Text; -end; - -{Add a text chunk} -procedure TPngObject.AddzTXt(const Keyword, Text: String); -var - TextChunk: TChunkzTXt; -begin - TextChunk := Chunks.Add(TChunkText) as TChunkzTXt; - TextChunk.Keyword := Keyword; - TextChunk.Text := Text; -end; - -{Removes the image transparency} -procedure TPngObject.RemoveTransparency; -var - TRNS: TChunkTRNS; -begin - TRNS := Chunks.ItemFromClass(TChunkTRNS) as TChunkTRNS; - if TRNS <> nil then Chunks.RemoveChunk(TRNS) -end; - -{Generates alpha information} -procedure TPngObject.CreateAlpha; -var - TRNS: TChunkTRNS; -begin - {Generates depending on the color type} - with Header do - case ColorType of - {Png allocates different memory space to hold alpha information} - {for these types} - COLOR_GRAYSCALE, COLOR_RGB: - begin - {Transform into the appropriate color type} - if ColorType = COLOR_GRAYSCALE then - ColorType := COLOR_GRAYSCALEALPHA - else ColorType := COLOR_RGBALPHA; - {Allocates memory to hold alpha information} - GetMem(ImageAlpha, Integer(Width) * Integer(Height)); - FillChar(ImageAlpha^, Integer(Width) * Integer(Height), #255); - end; - {Palette uses the TChunktRNS to store alpha} - COLOR_PALETTE: - begin - {Gets/creates TRNS chunk} - if Chunks.ItemFromClass(TChunkTRNS) = nil then - TRNS := Chunks.Add(TChunkTRNS) as TChunkTRNS - else - TRNS := Chunks.ItemFromClass(TChunkTRNS) as TChunkTRNS; - - {Prepares the TRNS chunk} - with TRNS do - begin - Fillchar(PaletteValues[0], 256, 255); - fDataSize := 1 shl Header.BitDepth; - fBitTransparency := False - end {with Chunks.Add}; - end; - end {case Header.ColorType} - -end; - -{Returns transparent color} -function TPngObject.GetTransparentColor: TColor; -var - TRNS: TChunkTRNS; -begin - TRNS := Chunks.ItemFromClass(TChunkTRNS) as TChunkTRNS; - {Reads the transparency chunk to get this info} - if Assigned(TRNS) then Result := TRNS.TransparentColor - else Result := 0 -end; - -{$OPTIMIZATION OFF} -procedure TPngObject.SetTransparentColor(const Value: TColor); -var - TRNS: TChunkTRNS; -begin - if HeaderPresent then - {Tests the ColorType} - case Header.ColorType of - {Not allowed for this modes} - COLOR_RGBALPHA, COLOR_GRAYSCALEALPHA: Self.RaiseError( - EPNGCannotChangeTransparent, EPNGCannotChangeTransparentText); - {Allowed} - COLOR_PALETTE, COLOR_RGB, COLOR_GRAYSCALE: - begin - TRNS := Chunks.ItemFromClass(TChunkTRNS) as TChunkTRNS; - if not Assigned(TRNS) then TRNS := Chunks.Add(TChunkTRNS) as TChunkTRNS; - - {Sets the transparency value from TRNS chunk} - TRNS.TransparentColor := {$IFDEF UseDelphi}ColorToRGB({$ENDIF}Value{$IFDEF UseDelphi}){$ENDIF} - end {COLOR_PALETTE, COLOR_RGB, COLOR_GRAYSCALE)} - end {case} -end; - -{Returns if header is present} -function TPngObject.HeaderPresent: Boolean; -begin - Result := ((Chunks.Count <> 0) and (Chunks.Item[0] is TChunkIHDR)) -end; - -{Returns pixel for png using palette and grayscale} -function GetByteArrayPixel(const png: TPngObject; const X, Y: Integer): TColor; -var - ByteData: Byte; - DataDepth: Byte; -begin - with png, Header do - begin - {Make sure the bitdepth is not greater than 8} - DataDepth := BitDepth; - if DataDepth > 8 then DataDepth := 8; - {Obtains the byte containing this pixel} - ByteData := pByteArray(png.Scanline[Y])^[X div (8 div DataDepth)]; - {Moves the bits we need to the right} - ByteData := (ByteData shr ((8 - DataDepth) - - (X mod (8 div DataDepth)) * DataDepth)); - {Discard the unwanted pixels} - ByteData:= ByteData and ($FF shr (8 - DataDepth)); - - {For palette mode map the palette entry and for grayscale convert and - returns the intensity} - case ColorType of - COLOR_PALETTE: - with TChunkPLTE(png.Chunks.ItemFromClass(TChunkPLTE)).Item[ByteData] do - Result := rgb(GammaTable[rgbRed], GammaTable[rgbGreen], - GammaTable[rgbBlue]); - COLOR_GRAYSCALE: - begin - ByteData := GammaTable[ByteData * ((1 shl DataDepth) + 1)]; - Result := rgb(ByteData, ByteData, ByteData); - end; - else Result := 0; - end {case}; - end {with} -end; - -{In case vcl units are not being used} -{$IFNDEF UseDelphi} -function ColorToRGB(const Color: TColor): COLORREF; -begin - Result := Color -end; -{$ENDIF} - -{Sets a pixel for grayscale and palette pngs} -procedure SetByteArrayPixel(const png: TPngObject; const X, Y: Integer; - const Value: TColor); -const - ClearFlag: Array[1..8] of Integer = (1, 3, 0, 15, 0, 0, 0, $FF); -var - ByteData: pByte; - DataDepth: Byte; - ValEntry: Byte; -begin - with png.Header do - begin - {Map into a palette entry} - ValEntry := GetNearestPaletteIndex(Png.Palette, ColorToRGB(Value)); - - {16 bits grayscale extra bits are discarted} - DataDepth := BitDepth; - if DataDepth > 8 then DataDepth := 8; - {Gets a pointer to the byte we intend to change} - ByteData := @pByteArray(png.Scanline[Y])^[X div (8 div DataDepth)]; - {Clears the old pixel data} - ByteData^ := ByteData^ and not (ClearFlag[DataDepth] shl ((8 - DataDepth) - - (X mod (8 div DataDepth)) * DataDepth)); - - {Setting the new pixel} - ByteData^ := ByteData^ or (ValEntry shl ((8 - DataDepth) - - (X mod (8 div DataDepth)) * DataDepth)); - end {with png.Header} -end; - -{Returns pixel when png uses RGB} -function GetRGBLinePixel(const png: TPngObject; - const X, Y: Integer): TColor; -begin - with pRGBLine(png.Scanline[Y])^[X] do - Result := RGB(rgbtRed, rgbtGreen, rgbtBlue) -end; - -{Sets pixel when png uses RGB} -procedure SetRGBLinePixel(const png: TPngObject; - const X, Y: Integer; Value: TColor); -begin - with pRGBLine(png.Scanline[Y])^[X] do - begin - rgbtRed := GetRValue(Value); - rgbtGreen := GetGValue(Value); - rgbtBlue := GetBValue(Value) - end -end; - -{Sets a pixel} -procedure TPngObject.SetPixels(const X, Y: Integer; const Value: TColor); -begin - if (X in [0..Width - 1]) and (Y in [0..Height - 1]) then - with Header do - begin - if ColorType in [COLOR_GRAYSCALE, COLOR_PALETTE] then - SetByteArrayPixel(Self, X, Y, Value) - else - SetRGBLinePixel(Self, X, Y, Value) - end {with} -end; - -{Returns a pixel} -function TPngObject.GetPixels(const X, Y: Integer): TColor; -begin - if (X in [0..Width - 1]) and (Y in [0..Height - 1]) then - with Header do - begin - if ColorType in [COLOR_GRAYSCALE, COLOR_PALETTE] then - Result := GetByteArrayPixel(Self, X, Y) - else - Result := GetRGBLinePixel(Self, X, Y) - end {with} - else Result := 0 -end; - -{Returns the image palette} -function TPngObject.GetPalette: HPALETTE; -var - LogPalette: TMaxLogPalette; - i: Integer; -begin - {Palette is avaliable for COLOR_PALETTE and COLOR_GRAYSCALE modes} - if (Header.ColorType in [COLOR_PALETTE, COLOR_GRAYSCALE]) then - begin - {In case the pal} - if TempPalette = 0 then - with LogPalette do - begin - {Prepares the new palette} - palVersion := $300; - palNumEntries := 256; - {Copy entries} - for i := 0 to LogPalette.palNumEntries - 1 do - begin - palPalEntry[i].peRed := Header.BitmapInfo.bmiColors[i].rgbRed; - palPalEntry[i].peGreen := Header.BitmapInfo.bmiColors[i].rgbGreen; - palPalEntry[i].peBlue := Header.BitmapInfo.bmiColors[i].rgbBlue; - palPalEntry[i].peFlags := 0; - end {for i}; - {Creates the palette} - TempPalette := CreatePalette(pLogPalette(@LogPalette)^); - end {with LogPalette, if Temppalette = 0} - end {if Header.ColorType in ...}; - Result := TempPalette; -end; - -initialization - {Initialize} - ChunkClasses := nil; - {crc table has not being computed yet} - crc_table_computed := FALSE; - {Register the necessary chunks for png} - RegisterCommonChunks; - {Registers TPNGObject to use with TPicture} - {$IFDEF UseDelphi}{$IFDEF RegisterGraphic} - TPicture.RegisterFileFormat('PNG', 'Portable Network Graphics', TPNGObject); - {$ENDIF}{$ENDIF} -finalization - {$IFDEF UseDelphi}{$IFDEF RegisterGraphic} - TPicture.UnregisterGraphicClass(TPNGObject); - {$ENDIF}{$ENDIF} - {Free chunk classes} - FreeChunkClassList; -end. - - -- cgit v1.2.3