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|
{* UltraStar Deluxe - Karaoke Game
*
* UltraStar Deluxe is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*
* $URL$
* $Id$
*}
unit UMediaCore_FFmpeg;
interface
{$IFDEF FPC}
{$MODE Delphi}
{$ENDIF}
{$I switches.inc}
uses
Classes,
ctypes,
sdl,
avcodec,
avformat,
avutil,
avio,
swscale,
UMusic,
ULog,
UPath;
type
PPacketQueue = ^TPacketQueue;
TPacketQueue = class
private
FirstListEntry: PAVPacketList;
LastListEntry: PAVPacketList;
PacketCount: integer;
Mutex: PSDL_Mutex;
Condition: PSDL_Cond;
Size: integer;
AbortRequest: boolean;
public
constructor Create();
destructor Destroy(); override;
function Put(Packet : PAVPacket): integer;
function PutStatus(StatusFlag: integer; StatusInfo: Pointer): integer;
procedure FreeStatusInfo(var Packet: TAVPacket);
function GetStatusInfo(var Packet: TAVPacket): Pointer;
function Get(var Packet: TAVPacket; Blocking: boolean): integer;
function GetSize(): integer;
procedure Flush();
procedure Abort();
function IsAborted(): boolean;
end;
const
STATUS_PACKET: PChar = 'STATUS_PACKET';
const
PKT_STATUS_FLAG_EOF = 1; // signal end-of-file
PKT_STATUS_FLAG_FLUSH = 2; // request the decoder to flush its avcodec decode buffers
PKT_STATUS_FLAG_ERROR = 3; // signal an error state
PKT_STATUS_FLAG_EMPTY = 4; // request the decoder to output empty data (silence or black frames)
type
TMediaCore_FFmpeg = class
private
AVCodecLock: PSDL_Mutex;
public
constructor Create();
destructor Destroy(); override;
class function GetInstance(): TMediaCore_FFmpeg;
function GetErrorString(ErrorNum: integer): string;
function FindStreamIDs(FormatCtx: PAVFormatContext; out FirstVideoStream, FirstAudioStream: integer ): boolean;
function FindAudioStreamIndex(FormatCtx: PAVFormatContext): integer;
function ConvertFFmpegToAudioFormat(FFmpegFormat: TAVSampleFormat; out Format: TAudioSampleFormat): boolean;
procedure LockAVCodec();
procedure UnlockAVCodec();
function AVFormatOpenInput(ps: PPAVFormatContext; filename: {const} PAnsiChar): Integer;
procedure AVFormatCloseInput(ps: PPAVFormatContext);
end;
implementation
uses
SysUtils,
UConfig;
{$IF LIBAVFORMAT_VERSION >= 54029104}
{ redeclaration of constants with the same names as deprecated
constants in order to reuse old callback definitions }
const
URL_RDONLY = 0; (**< read-only *)
URL_WRONLY = 1; (**< write-only *)
URL_RDWR = 2; (**< read-write *)
BLOCKSIZE = 4 * 1024;
{$ELSE}
function FFmpegStreamOpen(h: PURLContext; filename: PAnsiChar; flags: cint): cint; cdecl; forward;
function FFmpegStreamRead(h: PURLContext; buf: PByteArray; size: cint): cint; cdecl; forward;
function FFmpegStreamWrite(h: PURLContext; buf: PByteArray; size: cint): cint; cdecl; forward;
function FFmpegStreamSeek(h: PURLContext; pos: cint64; whence: cint): cint64; cdecl; forward;
function FFmpegStreamClose(h: PURLContext): cint; cdecl; forward;
const
UTF8FileProtocol: TURLProtocol = (
name: 'ufile';
url_open: FFmpegStreamOpen;
url_read: FFmpegStreamRead;
url_write: FFmpegStreamWrite;
url_seek: FFmpegStreamSeek;
url_close: FFmpegStreamClose;
);
{$ENDIF}
var
Instance: TMediaCore_FFmpeg;
function AV_VERSION_INT(a, b, c: cardinal): cuint;
begin
Result := (a shl 16) or (b shl 8) or c;
end;
procedure CheckVersions();
var
libVersion: cuint;
headerVersion: cuint;
function hexVerToStr(Version: cuint): string;
var
Major, Minor, Release: cardinal;
begin
Major := (Version shr 16) and $FF;;
Minor := (Version shr 8) and $FF;
Release := Version and $FF;
Result := Format('%d.%d.%d', [Major, Minor, Release]);
end;
begin
libVersion := avcodec_version();
headerVersion := AV_VERSION_INT(
LIBAVCODEC_VERSION_MAJOR,
LIBAVCODEC_VERSION_MINOR,
LIBAVCODEC_VERSION_RELEASE);
if (libVersion <> headerVersion) then
begin
Log.LogError(Format('%s header (%s) and DLL (%s) versions do not match.',
['libavcodec', hexVerToStr(headerVersion), hexVerToStr(libVersion)]));
end;
{$IF LIBAVFORMAT_VERSION >= 52020000} // 52.20.0
libVersion := avformat_version();
headerVersion := AV_VERSION_INT(
LIBAVFORMAT_VERSION_MAJOR,
LIBAVFORMAT_VERSION_MINOR,
LIBAVFORMAT_VERSION_RELEASE);
if (libVersion <> headerVersion) then
begin
Log.LogError(Format('%s header (%s) and DLL (%s) versions do not match.',
['libavformat', hexVerToStr(headerVersion), hexVerToStr(libVersion)]));
end;
{$IFEND}
{$IF LIBAVUTIL_VERSION >= 49008000} // 49.8.0
libVersion := avutil_version();
headerVersion := AV_VERSION_INT(
LIBAVUTIL_VERSION_MAJOR,
LIBAVUTIL_VERSION_MINOR,
LIBAVUTIL_VERSION_RELEASE);
if (libVersion <> headerVersion) then
begin
Log.LogError(Format('%s header (%s) and DLL (%s) versions do not match.',
['libavutil', hexVerToStr(headerVersion), hexVerToStr(libVersion)]));
end;
{$IFEND}
{$IF LIBSWSCALE_VERSION >= 000006001} // 0.6.1
libVersion := swscale_version();
headerVersion := AV_VERSION_INT(
LIBSWSCALE_VERSION_MAJOR,
LIBSWSCALE_VERSION_MINOR,
LIBSWSCALE_VERSION_RELEASE);
if (libVersion <> headerVersion) then
begin
Log.LogError(Format('%s header (%s) and DLL (%s) versions do not match.',
['libswscale', hexVerToStr(headerVersion), hexVerToStr(libVersion)]));
end;
{$IFEND}
end;
constructor TMediaCore_FFmpeg.Create();
begin
inherited;
CheckVersions();
{$IF LIBAVFORMAT_VERSION <= 52111000} // 52.110.0
av_register_protocol(@UTF8FileProtocol);
{$ELSEIF LIBAVFORMAT_VERSION < 54029104}
av_register_protocol2(@UTF8FileProtocol, sizeof(UTF8FileProtocol));
{$IFEND}
AVCodecLock := SDL_CreateMutex();
end;
destructor TMediaCore_FFmpeg.Destroy();
begin
SDL_DestroyMutex(AVCodecLock);
inherited;
end;
class function TMediaCore_FFmpeg.GetInstance(): TMediaCore_FFmpeg;
begin
if (not Assigned(Instance)) then
Instance := TMediaCore_FFmpeg.Create();
Result := Instance;
end;
procedure TMediaCore_FFmpeg.LockAVCodec();
begin
SDL_mutexP(AVCodecLock);
end;
procedure TMediaCore_FFmpeg.UnlockAVCodec();
begin
SDL_mutexV(AVCodecLock);
end;
function TMediaCore_FFmpeg.GetErrorString(ErrorNum: integer): string;
begin
{$IF LIBAVUTIL_VERSION < 50043000} // < 50.43.0
case ErrorNum of
AVERROR_IO: Result := 'AVERROR_IO';
AVERROR_NUMEXPECTED: Result := 'AVERROR_NUMEXPECTED';
AVERROR_INVALIDDATA: Result := 'AVERROR_INVALIDDATA';
AVERROR_NOMEM: Result := 'AVERROR_NOMEM';
AVERROR_NOFMT: Result := 'AVERROR_NOFMT';
AVERROR_NOTSUPP: Result := 'AVERROR_NOTSUPP';
AVERROR_NOENT: Result := 'AVERROR_NOENT';
AVERROR_PATCHWELCOME: Result := 'AVERROR_PATCHWELCOME';
else Result := 'AVERROR_#'+inttostr(ErrorNum);
end;
{$ELSE}
{$IFEND}
end;
{
@param(FormatCtx is a PAVFormatContext returned from av_open_input_file )
@param(FirstVideoStream is an OUT value of type integer, this is the index of the video stream)
@param(FirstAudioStream is an OUT value of type integer, this is the index of the audio stream)
@returns(@true on success, @false otherwise)
}
function TMediaCore_FFmpeg.FindStreamIDs(FormatCtx: PAVFormatContext; out FirstVideoStream, FirstAudioStream: integer): boolean;
var
i: integer;
Stream: PAVStream;
begin
// find the first video stream
FirstAudioStream := -1;
FirstVideoStream := -1;
for i := 0 to FormatCtx.nb_streams-1 do
begin
{$IF LIBAVFORMAT_VERSION <= 52111000} // <= 52.111.0
Stream := FormatCtx.streams[i];
{$ELSE}
Stream := PPAVStream(PtrUInt(FormatCtx.streams) + i * Sizeof(pointer))^;
{$IFEND}
{$IF LIBAVCODEC_VERSION < 52064000} // < 52.64.0
if (Stream.codec.codec_type = CODEC_TYPE_VIDEO) and
(FirstVideoStream < 0) then
begin
FirstVideoStream := i;
end;
if (Stream.codec.codec_type = CODEC_TYPE_AUDIO) and
(FirstAudioStream < 0) then
begin
FirstAudioStream := i;
end;
end;
{$ELSE}
if (Stream.codec.codec_type = AVMEDIA_TYPE_VIDEO) and
(FirstVideoStream < 0) then
begin
FirstVideoStream := i;
end;
if (Stream.codec.codec_type = AVMEDIA_TYPE_AUDIO) and
(FirstAudioStream < 0) then
begin
FirstAudioStream := i;
end;
end;
{$IFEND}
// return true if either an audio- or video-stream was found
Result := (FirstAudioStream > -1) or
(FirstVideoStream > -1) ;
end;
function TMediaCore_FFmpeg.FindAudioStreamIndex(FormatCtx: PAVFormatContext): integer;
var
i: integer;
StreamIndex: integer;
Stream: PAVStream;
begin
// find the first audio stream
StreamIndex := -1;
for i := 0 to FormatCtx^.nb_streams-1 do
begin
{$IF LIBAVFORMAT_VERSION <= 52111000} // <= 52.111.0
Stream := FormatCtx^.streams[i];
{$ELSE}
Stream := PPAVStream(PtrUInt(FormatCtx^.streams) + i * Sizeof(pointer))^;
{$IFEND}
{$IF LIBAVCODEC_VERSION < 52064000} // < 52.64.0
if (Stream.codec^.codec_type = CODEC_TYPE_AUDIO) then
{$ELSE}
if (Stream.codec^.codec_type = AVMEDIA_TYPE_AUDIO) then
{$IFEND}
begin
StreamIndex := i;
Break;
end;
end;
Result := StreamIndex;
end;
function TMediaCore_FFmpeg.ConvertFFmpegToAudioFormat(FFmpegFormat: TAVSampleFormat; out Format: TAudioSampleFormat): boolean;
begin
Result := true;
case FFmpegFormat of
AV_SAMPLE_FMT_U8: Format := asfU8;
AV_SAMPLE_FMT_S16: Format := asfS16;
AV_SAMPLE_FMT_S32: Format := asfS32;
AV_SAMPLE_FMT_FLT: Format := asfFloat;
AV_SAMPLE_FMT_DBL: Format := asfDouble;
else Result := false;
end;
end;
{**
* UTF-8 Filename wrapper based on:
* http://www.mail-archive.com/libav-user@mplayerhq.hu/msg02460.html
*}
{$IF LIBAVFORMAT_VERSION >= 54029104}
function FFmpegStreamOpen(Out h: Pointer; filename: PAnsiChar; flags: Integer): Integer;
{$ELSE}
function FFmpegStreamOpen(h: PURLContext; filename: PAnsiChar; flags: cint): cint; cdecl;
{$ENDIF}
var
Stream: TStream;
Mode: word;
ProtPrefix: string;
FilePath: IPath;
begin
// check for protocol prefix ('ufile:') and strip it
ProtPrefix := Format('%s:', ['ufile']);
if (StrLComp(filename, PChar(ProtPrefix), Length(ProtPrefix)) = 0) then
begin
Inc(filename, Length(ProtPrefix));
end;
FilePath := Path(filename);
if ((flags and URL_RDWR) = URL_RDWR) then
Mode := fmCreate
else if ((flags and URL_WRONLY) = URL_WRONLY) then
Mode := fmCreate // TODO: fmCreate is Read+Write -> reopen with fmOpenWrite
else
Mode := fmOpenRead or fmShareDenyWrite;
Result := 0;
try
Stream := TBinaryFileStream.Create(FilePath, Mode);
{$IF LIBAVFORMAT_VERSION >= 54029104}
h := Stream;
{$ELSE}
h.priv_data := Stream;
{$ENDIF}
except
{$IF LIBAVUTIL_VERSION < 50043000} // < 50.43.0
Result := AVERROR_NOENT;
{$ELSE}
Result := -1;
{$IFEND}
end;
end;
{$IF LIBAVFORMAT_VERSION >= 54029104}
function FFmpegStreamRead(h: Pointer; buf: PByteArray; size: cint): cint; cdecl;
{$ELSE}
function FFmpegStreamRead(h: PURLContext; buf: PByteArray; size: cint): cint; cdecl;
{$ENDIF}
var
Stream: TStream;
begin
{$IF LIBAVFORMAT_VERSION >= 54029104}
Stream := TStream(h);
{$ELSE}
Stream := TStream(h.priv_data);
{$ENDIF}
if (Stream = nil) then
raise EInvalidContainer.Create('FFmpegStreamRead on nil');
try
Result := Stream.Read(buf[0], size);
except
Result := -1;
end;
end;
{$IF LIBAVFORMAT_VERSION >= 54029104}
function FFmpegStreamWrite(h: Pointer; buf: PByteArray; size: cint): cint; cdecl;
{$ELSE}
function FFmpegStreamWrite(h: PURLContext; buf: PByteArray; size: cint): cint; cdecl;
{$ENDIF}
var
Stream: TStream;
begin
{$IF LIBAVFORMAT_VERSION >= 54029104}
Stream := TStream(h);
{$ELSE}
Stream := TStream(h.priv_data);
{$ENDIF}
if (Stream = nil) then
raise EInvalidContainer.Create('FFmpegStreamWrite on nil');
try
Result := Stream.Write(buf[0], size);
except
Result := -1;
end;
end;
{$IF LIBAVFORMAT_VERSION >= 54029104}
function FFmpegStreamSeek(h: Pointer; pos: cint64; whence: cint): cint64; cdecl;
{$ELSE}
function FFmpegStreamSeek(h: PURLContext; pos: cint64; whence: cint): cint64; cdecl;
{$ENDIF}
var
Stream : TStream;
Origin : TSeekOrigin;
begin
{$IF LIBAVFORMAT_VERSION >= 54029104}
Stream := TStream(h);
{$ELSE}
Stream := TStream(h.priv_data);
{$ENDIF}
if (Stream = nil) then
raise EInvalidContainer.Create('FFmpegStreamSeek on nil');
case whence of
0 {SEEK_SET}: Origin := soBeginning;
1 {SEEK_CUR}: Origin := soCurrent;
2 {SEEK_END}: Origin := soEnd;
AVSEEK_SIZE: begin
Result := Stream.Size;
Exit;
end
else
Origin := soBeginning;
end;
Result := Stream.Seek(pos, Origin);
end;
{$IF LIBAVFORMAT_VERSION >= 54029104}
function FFmpegStreamClose(h: Pointer): Integer;
{$ELSE}
function FFmpegStreamClose(h: PURLContext): cint; cdecl;
{$ENDIF}
var
Stream : TStream;
begin
{$IF LIBAVFORMAT_VERSION >= 54029104}
Stream := TStream(h);
{$ELSE}
Stream := TStream(h.priv_data);
{$ENDIF}
Stream.Free;
Result := 0;
end;
function TMediaCore_FFmpeg.AVFormatOpenInput(ps: PPAVFormatContext; filename: {const} PAnsiChar): Integer;
var
h: Pointer;
buffer: Pointer;
begin
{$IF LIBAVFORMAT_VERSION >= 54029104}
ps^ := avformat_alloc_context();
buffer := av_malloc(BLOCKSIZE);
FFmpegStreamOpen(h, filename, URL_RDONLY);
ps^^.pb := avio_alloc_context(buffer, BLOCKSIZE, 0, h, FFmpegStreamRead, FFmpegStreamWrite, FFmpegStreamSeek);
Result := avformat_open_input(ps, filename, nil, nil);
{$ELSE}
Result := 0;
{$ENDIF}
end;
procedure TMediaCore_FFmpeg.AVFormatCloseInput(ps: PPAVFormatContext);
begin
{$IF LIBAVFORMAT_VERSION >= 54029104}
av_free(ps^^.pb.buffer);
FFmpegStreamClose(ps^^.pb.opaque);
{ avformat_close_input frees AVIOContext pb, no avio_close needed }
{ avformat_close_input frees AVFormatContext, no additional avformat_free_context needed }
avformat_close_input(ps);
{$ENDIF}
end;
{ TPacketQueue }
constructor TPacketQueue.Create();
begin
inherited;
FirstListEntry := nil;
LastListEntry := nil;
PacketCount := 0;
Size := 0;
Mutex := SDL_CreateMutex();
Condition := SDL_CreateCond();
end;
destructor TPacketQueue.Destroy();
begin
Flush();
SDL_DestroyMutex(Mutex);
SDL_DestroyCond(Condition);
inherited;
end;
procedure TPacketQueue.Abort();
begin
SDL_LockMutex(Mutex);
AbortRequest := true;
SDL_CondBroadcast(Condition);
SDL_UnlockMutex(Mutex);
end;
function TPacketQueue.IsAborted(): boolean;
begin
SDL_LockMutex(Mutex);
Result := AbortRequest;
SDL_UnlockMutex(Mutex);
end;
function TPacketQueue.Put(Packet : PAVPacket): integer;
var
CurrentListEntry : PAVPacketList;
begin
Result := -1;
if (Packet = nil) then
Exit;
if (PChar(Packet^.data) <> STATUS_PACKET) then
begin
if (av_dup_packet(Packet) < 0) then
Exit;
end;
CurrentListEntry := av_malloc(SizeOf(TAVPacketList));
if (CurrentListEntry = nil) then
Exit;
CurrentListEntry^.pkt := Packet^;
CurrentListEntry^.next := nil;
SDL_LockMutex(Mutex);
try
if (LastListEntry = nil) then
FirstListEntry := CurrentListEntry
else
LastListEntry^.next := CurrentListEntry;
LastListEntry := CurrentListEntry;
Inc(PacketCount);
Size := Size + CurrentListEntry^.pkt.size;
SDL_CondSignal(Condition);
finally
SDL_UnlockMutex(Mutex);
end;
Result := 0;
end;
(**
* Adds a status packet (EOF, Flush, etc.) to the end of the queue.
* StatusInfo can be used to pass additional information to the decoder.
* Only assign nil or a valid pointer to data allocated with Getmem() to
* StatusInfo because the pointer will be disposed with Freemem() on a call
* to Flush(). If the packet is removed from the queue it is the decoder's
* responsibility to free the StatusInfo data with FreeStatusInfo().
*)
function TPacketQueue.PutStatus(StatusFlag: integer; StatusInfo: Pointer): integer;
var
TempPacket: PAVPacket;
begin
// create temp. package
TempPacket := av_malloc(SizeOf(TAVPacket));
if (TempPacket = nil) then
begin
Result := -1;
Exit;
end;
// init package
av_init_packet(TempPacket^);
TempPacket^.data := Pointer(STATUS_PACKET);
TempPacket^.flags := StatusFlag;
TempPacket^.priv := StatusInfo;
// put a copy of the package into the queue
Result := Put(TempPacket);
// data has been copied -> delete temp. package
av_free(TempPacket);
end;
procedure TPacketQueue.FreeStatusInfo(var Packet: TAVPacket);
begin
if (Packet.priv <> nil) then
FreeMem(Packet.priv);
end;
function TPacketQueue.GetStatusInfo(var Packet: TAVPacket): Pointer;
begin
Result := Packet.priv;
end;
function TPacketQueue.Get(var Packet: TAVPacket; Blocking: boolean): integer;
var
CurrentListEntry: PAVPacketList;
const
WAIT_TIMEOUT = 10; // timeout in ms
begin
Result := -1;
SDL_LockMutex(Mutex);
try
while (true) do
begin
if (AbortRequest) then
Exit;
CurrentListEntry := FirstListEntry;
if (CurrentListEntry <> nil) then
begin
FirstListEntry := CurrentListEntry^.next;
if (FirstListEntry = nil) then
LastListEntry := nil;
Dec(PacketCount);
Size := Size - CurrentListEntry^.pkt.size;
Packet := CurrentListEntry^.pkt;
av_free(CurrentListEntry);
Result := 1;
Break;
end
else if (not Blocking) then
begin
Result := 0;
Break;
end
else
begin
// block until a new package arrives,
// but do not wait till infinity to avoid deadlocks
if (SDL_CondWaitTimeout(Condition, Mutex, WAIT_TIMEOUT) = SDL_MUTEX_TIMEDOUT) then
begin
Result := 0;
Break;
end;
end;
end;
finally
SDL_UnlockMutex(Mutex);
end;
end;
function TPacketQueue.GetSize(): integer;
begin
SDL_LockMutex(Mutex);
Result := Size;
SDL_UnlockMutex(Mutex);
end;
procedure TPacketQueue.Flush();
var
CurrentListEntry, TempListEntry: PAVPacketList;
begin
SDL_LockMutex(Mutex);
CurrentListEntry := FirstListEntry;
while(CurrentListEntry <> nil) do
begin
TempListEntry := CurrentListEntry^.next;
// free status data
if (PChar(CurrentListEntry^.pkt.data) = STATUS_PACKET) then
FreeStatusInfo(CurrentListEntry^.pkt);
// free packet data
av_free_packet(@CurrentListEntry^.pkt);
// Note: param must be a pointer to a pointer!
av_freep(@CurrentListEntry);
CurrentListEntry := TempListEntry;
end;
LastListEntry := nil;
FirstListEntry := nil;
PacketCount := 0;
Size := 0;
SDL_UnlockMutex(Mutex);
end;
end.
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