- audio converter managed by media interface handler

- added (yet unused) interface priorities

git-svn-id: svn://svn.code.sf.net/p/ultrastardx/svn/branches/experimental@2700 b956fd51-792f-4845-bead-9b4dfca2ff2c

16 files changed, 309 insertions, 149 deletions

diff --git a/mediaplugin/src/base/UMusic.pas b/mediaplugin/src/base/UMusic.pas
index 182fef4c..e93a1037 100644
--- a/mediaplugin/src/base/UMusic.pas
+++ b/mediaplugin/src/base/UMusic.pas
@@ -331,36 +331,31 @@ type
       procedure SetLoop(Enabled: boolean);  override;
   end;
 
-  TVideoDecodeStream = class
+  TAudioConvertStream = class
+    protected
+      fSrcFormatInfo: TAudioFormatInfo;
+      fDstFormatInfo: TAudioFormatInfo;
     public
-      function Open(const FileName: IPath): boolean; virtual; abstract;
-      procedure Close; virtual; abstract;
-
-      procedure SetLoop(Enable: boolean); virtual; abstract;
-      function GetLoop(): boolean; virtual; abstract;
-
-      procedure SetPosition(Time: real); virtual; abstract;
-      function GetPosition: real; virtual; abstract;
-
-      function GetFrameAspect(): real; virtual; abstract;
-      function GetFrame(Time: Extended): PByteArray; virtual; abstract;
+      constructor Create(SrcFormatInfo: TAudioFormatInfo;
+                      DstFormatInfo: TAudioFormatInfo);
+      destructor Destroy(); override;
 
-      function GetFrameWidth(): integer; virtual; abstract;
-      function GetFrameHeight(): integer; virtual; abstract;
-  end;
+      (**
+       * Converts the InputBuffer and stores the result in OutputBuffer.
+       * If the result is not -1, InputSize will be set to the actual number of
+       * input-buffer bytes used.
+       * Returns the number of bytes written to the output-buffer or -1 if an error occured.
+       *)
+      function Convert(InputBuffer: PByteArray; OutputBuffer: PByteArray; var InputSize: integer): integer; virtual; abstract;
 
-type
-  // soundcard output-devices information
-  TAudioOutputDevice = class
-    public
-      Name: UTF8String; // soundcard name
-  end;
-  TAudioOutputDeviceList = array of TAudioOutputDevice;
+      (**
+       * Destination/Source size ratio
+       *)
+      function GetRatio(): double; virtual; abstract;
 
-type
-  IGenericPlayback = Interface
-  ['{63A5EBC3-3F4D-4F23-8DFB-B5165FCE33DD}']
-      function GetName: String;
+      function GetOutputBufferSize(InputSize: integer): integer; virtual; abstract;
+      property SrcFormatInfo: TAudioFormatInfo read fSrcFormatInfo;
+      property DstFormatInfo: TAudioFormatInfo read fDstFormatInfo;
   end;
 
   IVideo = interface
@@ -377,40 +372,40 @@ type
 
       procedure SetScreen(Screen: integer);
       function GetScreen(): integer;
-      
+
       procedure SetScreenPosition(X, Y: double; Z: double = 0.0);
       procedure GetScreenPosition(var X, Y, Z: double);
 
-      procedure  SetWidth(Width: double);
-       function GetWidth(): double;
-      
-      procedure  SetHeight(Height: double);
-       function GetHeight(): double;
-      
+      procedure SetWidth(Width: double);
+      function GetWidth(): double;
+
+      procedure SetHeight(Height: double);
+      function GetHeight(): double;
+
       {**
        * Sub-image of the video frame to draw.
        * This can be used for zooming or similar purposes.
        *}
       procedure SetFrameRange(Range: TRectCoords);
       function GetFrameRange(): TRectCoords;
-      
+
       function GetFrameAspect(): real;
-      
+
       procedure SetAspectCorrection(AspectCorrection: TAspectCorrection);
       function GetAspectCorrection(): TAspectCorrection;
-      
+
 
       procedure SetAlpha(Alpha: double);
       function GetAlpha(): double;
-      
+
       procedure SetReflectionSpacing(Spacing: double);
       function GetReflectionSpacing(): double;
 
       procedure GetFrame(Time: Extended);
       procedure Draw();
       procedure DrawReflection();
-       
-       
+
+
       property Screen: integer read GetScreen;
       property Width: double read GetWidth write SetWidth;
       property Height: double read GetHeight write SetHeight;
@@ -422,7 +417,44 @@ type
       property Position: real read GetPosition write SetPosition;
   end;
 
-  IVideoPlayback = Interface( IGenericPlayback )
+  TVideoDecodeStream = class
+    public
+      function Open(const FileName: IPath): boolean; virtual; abstract;
+      procedure Close; virtual; abstract;
+
+      procedure SetLoop(Enable: boolean); virtual; abstract;
+      function GetLoop(): boolean; virtual; abstract;
+
+      procedure SetPosition(Time: real); virtual; abstract;
+      function GetPosition: real; virtual; abstract;
+
+      function GetFrameAspect(): real; virtual; abstract;
+      function GetFrame(Time: Extended): PByteArray; virtual; abstract;
+
+      function GetFrameWidth(): integer; virtual; abstract;
+      function GetFrameHeight(): integer; virtual; abstract;
+  end;
+
+type
+  // soundcard output-devices information
+  TAudioOutputDevice = class
+    public
+      Name: UTF8String; // soundcard name
+  end;
+  TAudioOutputDeviceList = array of TAudioOutputDevice;
+
+type
+  IMediaInterface = interface
+  ['{9C31F7EF-76DB-4EEC-949F-009A26D553A2}']
+      function GetName: String;
+      function GetPriority(): integer;
+  end;
+
+  IGenericPlayback = interface(IMediaInterface)
+  ['{63A5EBC3-3F4D-4F23-8DFB-B5165FCE33DD}']
+  end;
+
+  IVideoPlayback = interface(IGenericPlayback)
   ['{3574C40C-28AE-4201-B3D1-3D1F0759B131}']
       function Init(): boolean;
       function Finalize: boolean;
@@ -430,15 +462,15 @@ type
       function Open(const FileName: IPath): IVideo;
   end;
 
-  IVideoVisualization = Interface( IVideoPlayback )
+  IVideoVisualization = interface(IVideoPlayback)
   ['{5AC17D60-B34D-478D-B632-EB00D4078017}']
   end;
 
-  IAudioPlayback = Interface( IGenericPlayback )
+  IAudioPlayback = interface(IGenericPlayback)
   ['{E4AE0B40-3C21-4DC5-847C-20A87E0DFB96}']
       function InitializePlayback: boolean;
       function FinalizePlayback: boolean;
-      
+
       function GetOutputDeviceList(): TAudioOutputDeviceList;
 
       procedure SetAppVolume(Volume: single);
@@ -484,27 +516,25 @@ type
       function CreateVoiceStream(ChannelMap: integer; FormatInfo: TAudioFormatInfo): TAudioVoiceStream;
   end;
 
-  IGenericDecoder = Interface
+  IGenericDecoder = interface(IMediaInterface)
   ['{557B0E9A-604D-47E4-B826-13769F3E10B7}']
-      function GetName(): string;
       function InitializeDecoder(): boolean;
       function FinalizeDecoder(): boolean;
       //function IsSupported(const Filename: string): boolean;
   end;
 
-  IVideoDecoder = Interface( IGenericDecoder )
+  IVideoDecoder = interface(IGenericDecoder)
   ['{2F184B2B-FE69-44D5-9031-0A2462391DCA}']
       function Open(const FileName: IPath): TVideoDecodeStream;
   end;
 
-  IAudioDecoder = Interface( IGenericDecoder )
+  IAudioDecoder = interface(IGenericDecoder)
   ['{AB47B1B6-2AA9-4410-BF8C-EC79561B5478}']
       function Open(const Filename: IPath): TAudioDecodeStream;
   end;
 
-  IAudioInput = Interface
+  IAudioInput = interface(IMediaInterface)
   ['{A5C8DA92-2A0C-4AB2-849B-2F7448C6003A}']
-      function GetName: String;
       function InitializeRecord: boolean;
       function FinalizeRecord(): boolean;
 
@@ -512,31 +542,13 @@ type
       procedure CaptureStop;
   end;
 
-type
-  TAudioConverter = class
-    protected
-      fSrcFormatInfo: TAudioFormatInfo;
-      fDstFormatInfo: TAudioFormatInfo;
-    public
-      function Init(SrcFormatInfo: TAudioFormatInfo; DstFormatInfo: TAudioFormatInfo): boolean; virtual;
-      destructor Destroy(); override;
-
-      (**
-       * Converts the InputBuffer and stores the result in OutputBuffer.
-       * If the result is not -1, InputSize will be set to the actual number of
-       * input-buffer bytes used.
-       * Returns the number of bytes written to the output-buffer or -1 if an error occured.
-       *)
-      function Convert(InputBuffer: PByteArray; OutputBuffer: PByteArray; var InputSize: integer): integer; virtual; abstract;
-
-      (**
-       * Destination/Source size ratio
-       *)
-      function GetRatio(): double; virtual; abstract;
+  IAudioConverter = interface(IMediaInterface)
+  ['{01FB458C-D631-4CA2-9E39-BF1B0ACB1AD7}']
+      function Init(): boolean;
+      function Finalize(): boolean;
 
-      function GetOutputBufferSize(InputSize: integer): integer; virtual; abstract;
-      property SrcFormatInfo: TAudioFormatInfo read fSrcFormatInfo;
-      property DstFormatInfo: TAudioFormatInfo read fDstFormatInfo;
+      function Open(SrcFormatInfo: TAudioFormatInfo;
+                    DstFormatInfo: TAudioFormatInfo): TAudioConvertStream;
   end;
 
 (* TODO
@@ -607,12 +619,13 @@ procedure InitializeSound;
 procedure InitializeVideo;
 procedure FinalizeMedia;
 
-function  Visualization(): IVideoPlayback;
-function  VideoPlayback(): IVideoPlayback;
-function  VideoDecoder(): IVideoDecoder;
-function  AudioPlayback(): IAudioPlayback;
-function  AudioInput(): IAudioInput;
-function  AudioDecoders(): TInterfaceList;
+function Visualization(): IVideoPlayback;
+function VideoPlayback(): IVideoPlayback;
+function VideoDecoder(): IVideoDecoder;
+function AudioPlayback(): IAudioPlayback;
+function AudioInput(): IAudioInput;
+function AudioDecoders(): TInterfaceList;
+function AudioConverter(): IAudioConverter;
 
 function  MediaManager: TInterfaceList;
 
@@ -635,6 +648,7 @@ var
   DefaultVisualization : IVideoPlayback;
   DefaultAudioPlayback : IAudioPlayback;
   DefaultAudioInput    : IAudioInput;
+  DefaultAudioConverter: IAudioConverter;
   AudioDecoderList     : TInterfaceList;
   MediaInterfaceList   : TInterfaceList;
 
@@ -719,6 +733,11 @@ begin
   Result := AudioDecoderList;
 end;
 
+function AudioConverter(): IAudioConverter;
+begin
+  Result := DefaultAudioConverter;
+end;
+
 procedure FilterInterfaceList(const IID: TGUID; InList, OutList: TInterfaceList);
 var
   i: integer;
@@ -745,6 +764,7 @@ var
   InterfaceList: TInterfaceList;
   CurrentAudioDecoder: IAudioDecoder;
   CurrentAudioPlayback: IAudioPlayback;
+  CurrentAudioConverter: IAudioConverter;
   CurrentAudioInput: IAudioInput;
 begin
   // create a temporary list for interface enumeration
@@ -781,6 +801,21 @@ begin
     MediaManager.Remove(CurrentAudioPlayback);
   end;
 
+  // find and initialize converter interface
+  DefaultAudioConverter := nil;
+  FilterInterfaceList(IAudioConverter, MediaManager, InterfaceList);
+  for i := 0 to InterfaceList.Count-1 do
+  begin
+    CurrentAudioConverter := InterfaceList[i] as IAudioConverter;
+    if (CurrentAudioConverter.Init()) then
+    begin
+      DefaultAudioConverter := CurrentAudioConverter;
+      break;
+    end;
+    Log.LogError('Initialize failed, Removing - '+ CurrentAudioConverter.GetName);
+    MediaManager.Remove(CurrentAudioConverter);
+  end;
+
   // find and initialize input interface
   DefaultAudioInput := nil;
   FilterInterfaceList(IAudioInput, MediaManager, InterfaceList);
@@ -879,7 +914,9 @@ begin
   FreeAndNil(AudioDecoderList);
   DefaultAudioPlayback := nil;
   DefaultAudioInput := nil;
+  DefaultAudioConverter := nil;
   DefaultVideoPlayback := nil;
+  DefaultVideoDecoder := nil;
   DefaultVisualization := nil;
 
   // create temporary interface list
@@ -900,17 +937,22 @@ begin
   for i := 0 to InterfaceList.Count-1 do
     (InterfaceList[i] as IAudioDecoder).FinalizeDecoder();
 
+  // finalize audio converter interfaces
+  FilterInterfaceList(IAudioConverter, MediaManager, InterfaceList);
+  for i := 0 to InterfaceList.Count-1 do
+    (InterfaceList[i] as IAudioConverter).Finalize();
+
   // finalize video interfaces
   FilterInterfaceList(IVideoPlayback, MediaManager, InterfaceList);
   for i := 0 to InterfaceList.Count-1 do
     (InterfaceList[i] as IVideoPlayback).Finalize();
 
-  // finalize video interfaces
+  // finalize video decoder interfaces
   FilterInterfaceList(IVideoDecoder, MediaManager, InterfaceList);
   for i := 0 to InterfaceList.Count-1 do
     (InterfaceList[i] as IVideoDecoder).FinalizeDecoder();
 
-  // finalize audio decoder interfaces
+  // finalize visualization interfaces
   FilterInterfaceList(IVideoVisualization, MediaManager, InterfaceList);
   for i := 0 to InterfaceList.Count-1 do
     (InterfaceList[i] as IVideoVisualization).Finalize();
@@ -945,6 +987,7 @@ begin
   writeln( '--------------------------------------------------------------' );
   writeln( 'Registered Audio Playback Interface : ' + AudioPlayback.GetName );
   writeln( 'Registered Audio Input    Interface : ' + AudioInput.GetName    );
+  writeln( 'Registered Audio Converter Interface: ' + AudioConverter.GetName    );
   writeln( 'Registered Video Playback Interface : ' + VideoPlayback.GetName );
   writeln( 'Registered Video Decoder  Interface : ' + VideoDecoder.GetName );
   writeln( 'Registered Visualization  Interface : ' + Visualization.GetName );
@@ -1049,16 +1092,16 @@ begin
   end;
 end;
 
-{ TAudioConverter }
+{ TAudioConvertStream }
 
-function TAudioConverter.Init(SrcFormatInfo: TAudioFormatInfo; DstFormatInfo: TAudioFormatInfo): boolean;
+constructor TAudioConvertStream.Create(
+  SrcFormatInfo: TAudioFormatInfo; DstFormatInfo: TAudioFormatInfo);
 begin
   fSrcFormatInfo := SrcFormatInfo.Copy();
   fDstFormatInfo := DstFormatInfo.Copy();
-  Result := true;
 end;
 
-destructor TAudioConverter.Destroy();
+destructor TAudioConvertStream.Destroy();
 begin
   FreeAndNil(fSrcFormatInfo);
   FreeAndNil(fDstFormatInfo);
diff --git a/mediaplugin/src/base/URecord.pas b/mediaplugin/src/base/URecord.pas
index 5cddcc77..de567aba 100644
--- a/mediaplugin/src/base/URecord.pas
+++ b/mediaplugin/src/base/URecord.pas
@@ -176,6 +176,7 @@ type
       function UnifyDeviceName(const name: UTF8String; deviceIndex: integer): UTF8String;
     public
       function GetName: String;           virtual; abstract;
+      function GetPriority: integer;      virtual; abstract;
       function InitializeRecord: boolean; virtual; abstract;
       function FinalizeRecord: boolean;   virtual;
 
diff --git a/mediaplugin/src/media/UAudioConverter.pas b/mediaplugin/src/media/UAudioConverter.pas
index 7826c265..de6840ca 100644
--- a/mediaplugin/src/media/UAudioConverter.pas
+++ b/mediaplugin/src/media/UAudioConverter.pas
@@ -47,27 +47,30 @@ uses
   Math;
 
 type
-  {*
-   * Notes:
-   *  - 44.1kHz to 48kHz conversion or vice versa is not supported
-   *    by SDL 1.2 (will be introduced in 1.3).
-   *    No conversion takes place in this cases.
-   *    This is because SDL just converts differences in powers of 2.
-   *    So the result might not be that accurate.
-   *    This IS audible (voice to high/low) and it needs good synchronization
-   *    with the video or the lyrics timer.
-   *  - float<->int16 conversion is not supported (will be part of 1.3) and
-   *    SDL (<1.3) is not capable of handling floats at all.
-   *  -> Using FFmpeg or libsamplerate for resampling is preferred.
-   *     Use SDL for channel and format conversion only.
-   *}
-  TAudioConverter_SDL = class(TAudioConverter)
+  TAudioConverter_SDL = class(TInterfacedObject, IAudioConverter)
+    public
+      function GetName(): string;
+      function GetPriority(): integer;
+      function Init(): boolean;
+      function Finalize(): boolean;
+
+      function Open(SrcFormatInfo: TAudioFormatInfo;
+                    DstFormatInfo: TAudioFormatInfo): TAudioConvertStream;
+  end;
+
+  TAudioConvertStream_SDL = class(TAudioConvertStream)
     private
       cvt: TSDL_AudioCVT;
+      function Init(): boolean;
+    protected
+      constructor Create(SrcFormatInfo: TAudioFormatInfo;
+                    DstFormatInfo: TAudioFormatInfo);
     public
-      function Init(SrcFormatInfo: TAudioFormatInfo; DstFormatInfo: TAudioFormatInfo): boolean; override;
       destructor Destroy(); override;
 
+      class function Open(SrcFormatInfo: TAudioFormatInfo;
+                    DstFormatInfo: TAudioFormatInfo): TAudioConvertStream_SDL;
+
       function Convert(InputBuffer: PByteArray; OutputBuffer: PByteArray; var InputSize: integer): integer; override;
       function GetOutputBufferSize(InputSize: integer): integer; override;
       function GetRatio(): double; override;
@@ -115,18 +118,85 @@ type
   // if people sing along with the song.
   // But FFmpeg might offer a better quality/speed ratio than SRC_LINEAR.
   const
-    SRC_CONVERTER_TYPE = SRC_LINEAR; 
+    SRC_CONVERTER_TYPE = SRC_LINEAR;
   {$ENDIF}
 
 implementation
 
-function TAudioConverter_SDL.Init(srcFormatInfo: TAudioFormatInfo; dstFormatInfo: TAudioFormatInfo): boolean;
+{ TAudioConverter_SDL }
+
+function TAudioConverter_SDL.GetName(): string;
+begin
+  Result := 'AudioConverter_SDL';
+end;
+
+function TAudioConverter_SDL.GetPriority(): integer;
+begin
+  {* Notes:
+   *  - 44.1kHz to 48kHz conversion or vice versa is not supported
+   *    by SDL 1.2 (will be introduced in 1.3).
+   *    No conversion takes place in this cases.
+   *    This is because SDL just converts differences in powers of 2.
+   *    So the result might not be that accurate.
+   *    This IS audible (voice to high/low) and it needs good synchronization
+   *    with the video or the lyrics timer.
+   *  - float<->int16 conversion is not supported (will be part of 1.3) and
+   *    SDL (<1.3) is not capable of handling floats at all.
+   *  -> Using FFmpeg or libsamplerate for resampling is preferred.
+   *     Use SDL for channel and format conversion only.
+   *}
+  Result := 0;
+end;
+
+function TAudioConverter_SDL.Init(): boolean;
+begin
+  Result := true;
+end;
+
+function TAudioConverter_SDL.Finalize(): boolean;
+begin
+  Result := true;
+end;
+
+function TAudioConverter_SDL.Open(SrcFormatInfo: TAudioFormatInfo;
+  DstFormatInfo: TAudioFormatInfo): TAudioConvertStream;
+begin
+  Result := TAudioConvertStream_SDL.Open(SrcFormatInfo, DstFormatInfo);
+end;
+
+{ TAudioConvertStream_SDL }
+
+constructor TAudioConvertStream_SDL.Create(SrcFormatInfo: TAudioFormatInfo;
+  DstFormatInfo: TAudioFormatInfo);
+begin
+  inherited Create(SrcFormatInfo, DstFormatInfo);
+end;
+
+destructor TAudioConvertStream_SDL.Destroy();
+begin
+  inherited;
+end;
+
+class function TAudioConvertStream_SDL.Open(SrcFormatInfo: TAudioFormatInfo;
+  DstFormatInfo: TAudioFormatInfo): TAudioConvertStream_SDL;
+var
+  Stream: TAudioConvertStream_SDL;
+begin
+  Result := nil;
+  Stream := TAudioConvertStream_SDL.Create(SrcFormatInfo, DstFormatInfo);
+  if (not Stream.Init()) then
+  begin
+    Stream.Free;
+    Exit;
+  end;
+  Result := Stream;
+end;
+
+function TAudioConvertStream_SDL.Init(): boolean;
 var
   srcFormat: UInt16;
   dstFormat: UInt16;
 begin
-  inherited Init(SrcFormatInfo, DstFormatInfo);
-
   Result := false;
 
   if (not ConvertAudioFormatToSDL(srcFormatInfo.Format, srcFormat) or
@@ -147,29 +217,23 @@ begin
   Result := true;
 end;
 
-destructor TAudioConverter_SDL.Destroy();
-begin
-  // nothing to be done here
-  inherited;
-end;
-
 (*
  * Returns the size of the output buffer. This might be bigger than the actual
  * size of resampled audio data.
  *)
-function TAudioConverter_SDL.GetOutputBufferSize(InputSize: integer): integer;
+function TAudioConvertStream_SDL.GetOutputBufferSize(InputSize: integer): integer;
 begin
   // Note: len_ratio must not be used here. Even if the len_ratio is 1.0, len_mult might be 2.
   // Example: 44.1kHz/mono to 22.05kHz/stereo -> len_ratio=1, len_mult=2
   Result := InputSize * cvt.len_mult;
 end;
 
-function TAudioConverter_SDL.GetRatio(): double;
+function TAudioConvertStream_SDL.GetRatio(): double;
 begin
   Result := cvt.len_ratio;
 end;
 
-function TAudioConverter_SDL.Convert(InputBuffer: PByteArray; OutputBuffer: PByteArray; var InputSize: integer): integer;
+function TAudioConvertStream_SDL.Convert(InputBuffer: PByteArray; OutputBuffer: PByteArray; var InputSize: integer): integer;
 begin
   Result := -1;
 
@@ -457,4 +521,7 @@ end;
 
 {$ENDIF}
 
+initialization
+  MediaManager.add(TAudioConverter_SDL.Create);
+
 end.
\ No newline at end of file
diff --git a/mediaplugin/src/media/UAudioDecoderPlugin.pas b/mediaplugin/src/media/UAudioDecoderPlugin.pas
index 8298cf17..e518277c 100644
--- a/mediaplugin/src/media/UAudioDecoderPlugin.pas
+++ b/mediaplugin/src/media/UAudioDecoderPlugin.pas
@@ -56,7 +56,8 @@ type
     public
       constructor Create(Info: PMediaPluginInfo);
 
-      function GetName: string;
+      function GetName(): string;
+      function GetPriority(): integer;
 
       function InitializeDecoder(): boolean;
       function FinalizeDecoder(): boolean;
@@ -211,6 +212,11 @@ begin
   Result := 'Plugin:AudioDecoder:' + fPluginInfo.name;
 end;
 
+function TAudioDecoderPlugin.GetPriority(): integer;
+begin
+  Result := fPluginInfo.audioDecoder.priority;
+end;
+
 function TAudioDecoderPlugin.InitializeDecoder: boolean;
 begin
   //fPluginInfo.initialize();
diff --git a/mediaplugin/src/media/UAudioDecoder_Bass.pas b/mediaplugin/src/media/UAudioDecoder_Bass.pas
index d6d2425a..e08b91ff 100644
--- a/mediaplugin/src/media/UAudioDecoder_Bass.pas
+++ b/mediaplugin/src/media/UAudioDecoder_Bass.pas
@@ -73,6 +73,7 @@ type
   TAudioDecoder_Bass = class( TInterfacedObject, IAudioDecoder )
     public
       function GetName: string;
+      function GetPriority: integer;
 
       function InitializeDecoder(): boolean;
       function FinalizeDecoder(): boolean;
@@ -209,7 +210,12 @@ end;
 
 function TAudioDecoder_Bass.GetName: String;
 begin
-  result := 'BASS_Decoder';
+  Result := 'BASS_Decoder';
+end;
+
+function TAudioDecoder_Bass.GetPriority: integer;
+begin
+  Result := 90;
 end;
 
 function TAudioDecoder_Bass.InitializeDecoder(): boolean;
diff --git a/mediaplugin/src/media/UAudioInput_Bass.pas b/mediaplugin/src/media/UAudioInput_Bass.pas
index 0e79b343..f95c0aa1 100644
--- a/mediaplugin/src/media/UAudioInput_Bass.pas
+++ b/mediaplugin/src/media/UAudioInput_Bass.pas
@@ -59,6 +59,7 @@ type
       function EnumDevices(): boolean;
     public
       function GetName: String; override;
+      function GetPriority: integer; override;
       function InitializeRecord: boolean; override;
       function FinalizeRecord: boolean; override;
   end;
@@ -346,9 +347,14 @@ end;
 
 { TAudioInput_Bass }
 
-function  TAudioInput_Bass.GetName: String;
+function TAudioInput_Bass.GetName: String;
 begin
-  result := 'BASS_Input';
+  Result := 'BASS_Input';
+end;
+
+function TAudioInput_Bass.GetPriority: integer;
+begin
+  Result := 90;
 end;
 
 function TAudioInput_Bass.EnumDevices(): boolean;
diff --git a/mediaplugin/src/media/UAudioInput_Portaudio.pas b/mediaplugin/src/media/UAudioInput_Portaudio.pas
index c7364eb4..ad93c12a 100644
--- a/mediaplugin/src/media/UAudioInput_Portaudio.pas
+++ b/mediaplugin/src/media/UAudioInput_Portaudio.pas
@@ -61,6 +61,7 @@ type
       function EnumDevices(): boolean;
     public
       function GetName: string; override;
+      function GetPriority: integer; override;
       function InitializeRecord: boolean; override;
       function FinalizeRecord: boolean; override;
   end;
@@ -311,7 +312,12 @@ end;
 
 function TAudioInput_Portaudio.GetName: String;
 begin
-  result := 'Portaudio';
+  Result := 'Portaudio';
+end;
+
+function TAudioInput_Portaudio.GetPriority: integer;
+begin
+  Result := 40;
 end;
 
 function TAudioInput_Portaudio.EnumDevices(): boolean;
diff --git a/mediaplugin/src/media/UAudioPlaybackBase.pas b/mediaplugin/src/media/UAudioPlaybackBase.pas
index 5f317257..65528430 100644
--- a/mediaplugin/src/media/UAudioPlaybackBase.pas
+++ b/mediaplugin/src/media/UAudioPlaybackBase.pas
@@ -52,6 +52,7 @@ type
       function OpenDecodeStream(const Filename: IPath): TAudioDecodeStream;
     public
       function GetName: string; virtual; abstract;
+      function GetPriority: integer; virtual; abstract;
 
       function Open(const Filename: IPath): boolean; // true if succeed
       procedure Close;
diff --git a/mediaplugin/src/media/UAudioPlayback_Bass.pas b/mediaplugin/src/media/UAudioPlayback_Bass.pas
index 1d7a44dc..0cdf8624 100644
--- a/mediaplugin/src/media/UAudioPlayback_Bass.pas
+++ b/mediaplugin/src/media/UAudioPlayback_Bass.pas
@@ -121,6 +121,8 @@ type
       function CreatePlaybackStream(): TAudioPlaybackStream; override;
     public
       function GetName: String; override;
+      function GetPriority: integer; override;
+
       function InitializePlayback(): boolean; override;
       function FinalizePlayback: boolean; override;
       procedure SetAppVolume(Volume: single); override;
@@ -649,6 +651,11 @@ begin
   Result := 'BASS_Playback';
 end;
 
+function TAudioPlayback_Bass.GetPriority: integer;
+begin
+  Result := 90;
+end;
+
 function TAudioPlayback_Bass.EnumDevices(): boolean;
 var
   BassDeviceID: DWORD;
diff --git a/mediaplugin/src/media/UAudioPlayback_SDL.pas b/mediaplugin/src/media/UAudioPlayback_SDL.pas
index 8403ef03..cbc3056b 100644
--- a/mediaplugin/src/media/UAudioPlayback_SDL.pas
+++ b/mediaplugin/src/media/UAudioPlayback_SDL.pas
@@ -57,7 +57,8 @@ type
       function FinalizeAudioPlaybackEngine(): boolean;   override;
       function GetLatency(): double;                     override;
     public
-      function GetName: String;                          override;
+      function GetName: String; override;
+      function GetPriority: integer; override;
       procedure MixBuffers(dst, src: PByteArray; size: Cardinal; volume: Single); override;
   end;
 
@@ -77,6 +78,11 @@ begin
   Result := 'SDL_Playback';
 end;
 
+function TAudioPlayback_SDL.GetPriority: integer;
+begin
+  Result := 60;
+end;
+
 function TAudioPlayback_SDL.EnumDevices(): boolean;
 begin
   // Note: SDL does not provide Device-Selection capabilities (will be introduced in 1.3)
diff --git a/mediaplugin/src/media/UAudioPlayback_SoftMixer.pas b/mediaplugin/src/media/UAudioPlayback_SoftMixer.pas
index b8148b4a..39f71147 100644
--- a/mediaplugin/src/media/UAudioPlayback_SoftMixer.pas
+++ b/mediaplugin/src/media/UAudioPlayback_SoftMixer.pas
@@ -59,7 +59,7 @@ type
       SourceBufferSize:  integer;
       SourceBufferCount: integer; // number of available bytes in SourceBuffer
 
-      Converter: TAudioConverter;
+      Converter: TAudioConvertStream;
       Status:    TStreamStatus;
       InternalLock: PSDL_Mutex;
       SoundEffects: TList;
@@ -73,7 +73,6 @@ type
       procedure Reset();
 
       procedure ApplySoundEffects(Buffer: PByteArray; BufferSize: integer);
-      function InitFormatConversion(): boolean;
       procedure FlushBuffers();
 
       procedure LockSampleBuffer(); {$IFDEF HasInline}inline;{$ENDIF}
@@ -387,7 +386,9 @@ begin
     Exit;
   Self.SourceStream := SourceStream;
 
-  if not InitFormatConversion() then
+  Converter := AudioConverter.Open(SourceStream.GetAudioFormatInfo(),
+      GetAudioFormatInfo());
+  if (Converter = nil) then
   begin
     // reset decode-stream so it will not be freed on destruction
     Self.SourceStream := nil;
@@ -422,28 +423,6 @@ begin
   SDL_mutexV(InternalLock);
 end;
 
-function TGenericPlaybackStream.InitFormatConversion(): boolean;
-var
-  SrcFormatInfo: TAudioFormatInfo;
-  DstFormatInfo: TAudioFormatInfo;
-begin
-  Result := false;
-
-  SrcFormatInfo := SourceStream.GetAudioFormatInfo();
-  DstFormatInfo := GetAudioFormatInfo();
-
-  // TODO: selection should not be done here, use a factory (TAudioConverterFactory) instead 
-  {$IF Defined(UseFFmpegResample)}
-  Converter := TAudioConverterPlugin.Create();
-  {$ELSEIF Defined(UseSRCResample)}
-  Converter := TAudioConverter_SRC.Create();
-  {$ELSE}
-  Converter := TAudioConverter_SDL.Create();
-  {$IFEND}
-
-  Result := Converter.Init(SrcFormatInfo, DstFormatInfo);
-end;
-
 procedure TGenericPlaybackStream.Play();
 var
   Mixer: TAudioMixerStream;
diff --git a/mediaplugin/src/media/UMediaPlugin.pas b/mediaplugin/src/media/UMediaPlugin.pas
index 9f3c8160..762b5af0 100644
--- a/mediaplugin/src/media/UMediaPlugin.pas
+++ b/mediaplugin/src/media/UMediaPlugin.pas
@@ -91,6 +91,7 @@ type
 
   PAudioDecoderInfo = ^TAudioDecoderInfo;
   TAudioDecoderInfo = record
+    priority: cint;
     open: function(filename: PAnsiChar): PAudioDecodeStream; cdecl;
     close: procedure(stream: PAudioDecodeStream); cdecl;
     getLength: function(stream: PAudioDecodeStream): double; cdecl;
@@ -106,6 +107,7 @@ type
 
   PAudioConverterInfo = ^TAudioConverterInfo;
   TAudioConverterInfo = record
+    priority: cint;
     open: function(inputFormat: PCAudioFormatInfo; outputFormat: PCAudioFormatInfo): PAudioConvertStream; cdecl;
     close: procedure(stream: PAudioConvertStream); cdecl;
     convert: function(stream: PAudioConvertStream; input, output: PCuint8; numSamples: PCint): cint; cdecl;
@@ -115,6 +117,7 @@ type
 
   PVideoDecoderInfo = ^TVideoDecoderInfo;
   TVideoDecoderInfo = record
+    priority: cint;
     open: function(filename: PAnsiChar): PVideoDecodeStream; cdecl;
     close: procedure(stream: PVideoDecodeStream); cdecl;
     setLoop: procedure(stream: PVideoDecodeStream; enable: cbool); cdecl;
diff --git a/mediaplugin/src/media/UMedia_dummy.pas b/mediaplugin/src/media/UMedia_dummy.pas
index 46cbe6b8..1ada6603 100644
--- a/mediaplugin/src/media/UMedia_dummy.pas
+++ b/mediaplugin/src/media/UMedia_dummy.pas
@@ -49,6 +49,7 @@ type
     public
       constructor Create();
       function GetName: string;
+      function GetPriority: integer;
 
       function Init(): boolean;
       function Finalize(): boolean;
@@ -157,6 +158,7 @@ type
     public
       constructor Create();
       function GetName: string;
+      function GetPriority: integer;
 
       function Init(): boolean;
       function Finalize(): boolean;
@@ -169,6 +171,11 @@ begin
   Result := 'AudioDummy';
 end;
 
+function TAudio_Dummy.GetPriority: integer;
+begin
+  Result := -100;
+end;
+
 constructor TAudio_Dummy.Create();
 begin
   inherited;
@@ -469,6 +476,11 @@ begin
   Result := 'VideoDummy';
 end;
 
+function TVideoPlayback_Dummy.GetPriority: integer;
+begin
+  Result := -100;
+end;
+
 function TVideoPlayback_Dummy.Init(): boolean;
 begin
   Result := true;
diff --git a/mediaplugin/src/media/UVideo.pas b/mediaplugin/src/media/UVideo.pas
index 6caf9658..d7fab209 100644
--- a/mediaplugin/src/media/UVideo.pas
+++ b/mediaplugin/src/media/UVideo.pas
@@ -170,6 +170,7 @@ type
   TVideoPlayback_FFmpeg = class( TInterfacedObject, IVideoPlayback )
   public
     function GetName: String;
+    function GetPriority: integer;
 
     function Init(): boolean;
     function Finalize: boolean;
@@ -183,7 +184,12 @@ type
 
 function  TVideoPlayback_FFmpeg.GetName: String;
 begin
-  result := 'OpenGL_VideoPlayback';
+  Result := 'OpenGL_VideoPlayback';
+end;
+
+function TVideoPlayback_FFmpeg.GetPriority: integer;
+begin
+  Result := 80;
 end;
 
 function TVideoPlayback_FFmpeg.Init(): boolean;
@@ -236,7 +242,6 @@ function TVideo_FFmpeg.Open(const Decoder: TVideoDecodeStream): boolean;
 var
   glErr: GLenum;
 begin
-  Result := false;
   Reset();
 
   fDecoder := Decoder;
diff --git a/mediaplugin/src/media/UVideoDecoderPlugin.pas b/mediaplugin/src/media/UVideoDecoderPlugin.pas
index 684b6031..d513a0b3 100644
--- a/mediaplugin/src/media/UVideoDecoderPlugin.pas
+++ b/mediaplugin/src/media/UVideoDecoderPlugin.pas
@@ -45,7 +45,8 @@ type
   public
     constructor Create(Info: PMediaPluginInfo);
 
-    function GetName: String;
+    function GetName(): String;
+    function GetPriority(): integer;
 
     function InitializeDecoder(): boolean;
     function FinalizeDecoder: boolean;
@@ -98,11 +99,16 @@ begin
   fPluginInfo := Info;
 end;
 
-function  TVideoDecoderPlugin.GetName: String;
+function TVideoDecoderPlugin.GetName(): String;
 begin
   Result := 'Plugin:VideoDecoder:' + fPluginInfo.name;
 end;
 
+function TVideoDecoderPlugin.GetPriority(): integer;
+begin
+  Result := fPluginInfo.videoDecoder.priority;
+end;
+
 function TVideoDecoderPlugin.InitializeDecoder(): boolean;
 begin
   //fPluginInfo.initialize();
diff --git a/mediaplugin/src/media/UVisualizer.pas b/mediaplugin/src/media/UVisualizer.pas
index 1cdc3500..d7fc460c 100644
--- a/mediaplugin/src/media/UVisualizer.pas
+++ b/mediaplugin/src/media/UVisualizer.pas
@@ -183,6 +183,7 @@ type
 
     public
       function GetName: String;
+      function GetPriority: integer;
 
       function Init(): boolean;
       function Finalize(): boolean;
@@ -198,6 +199,11 @@ begin
   Result := 'ProjectM';
 end;
 
+function TVideoPlayback_ProjectM.GetPriority: integer;
+begin
+  Result := 80;
+end;
+
 function TVideoPlayback_ProjectM.Init(): boolean;
 begin
   Result := true;