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-rw-r--r--mediaplugin/src/media/UAudioConverter_SRC.pas335
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diff --git a/mediaplugin/src/media/UAudioConverter_SRC.pas b/mediaplugin/src/media/UAudioConverter_SRC.pas
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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 UAudioConverter_SRC;
+
+interface
+
+{$IFDEF FPC}
+ {$MODE Delphi}
+{$ENDIF}
+
+{$I switches.inc}
+
+uses
+ UMusic,
+ ULog,
+ samplerate,
+ UMediaPlugin,
+ SysUtils,
+ Math;
+
+type
+ TAudioConverter_SRC = 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_SRC = class(TAudioConvertStream)
+ private
+ ConverterState: PSRC_STATE;
+ ConversionData: SRC_DATA;
+ FormatConverter: TAudioConvertStream;
+ function Init(): boolean;
+ protected
+ constructor Create(SrcFormatInfo: TAudioFormatInfo;
+ DstFormatInfo: TAudioFormatInfo);
+ public
+ destructor Destroy(); override;
+
+ class function Open(SrcFormatInfo: TAudioFormatInfo;
+ DstFormatInfo: TAudioFormatInfo): TAudioConvertStream_SRC;
+
+ function Convert(InputBuffer: PByteArray; OutputBuffer: PByteArray; var InputSize: integer): integer; override;
+ function GetOutputBufferSize(InputSize: integer): integer; override;
+ function GetRatio(): double; override;
+ end;
+
+ // Note: SRC (=libsamplerate) provides several converters with different quality
+ // speed trade-offs. The SINC-types are slow but offer best quality.
+ // The SRC_SINC_* converters are too slow for realtime conversion,
+ // (SRC_SINC_FASTEST is approx. ten times slower than SRC_LINEAR) resulting
+ // in audible clicks and pops.
+ // SRC_LINEAR is very fast and should have a better quality than SRC_ZERO_ORDER_HOLD
+ // because it interpolates the samples. Normal "non-audiophile" users should not
+ // be able to hear a difference between the SINC_* ones and LINEAR. Especially
+ // 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;
+
+implementation
+
+uses
+ ctypes,
+ UAudioConverter_SDL;
+
+{ TAudioConverter_SRC }
+
+function TAudioConverter_SRC.GetName(): string;
+begin
+ Result := 'AudioConverter_SRC';
+end;
+
+function TAudioConverter_SRC.GetPriority(): integer;
+begin
+ Result := 30;
+end;
+
+function TAudioConverter_SRC.Init(): boolean;
+begin
+ Result := true;
+end;
+
+function TAudioConverter_SRC.Finalize(): boolean;
+begin
+ Result := true;
+end;
+
+function TAudioConverter_SRC.Open(SrcFormatInfo: TAudioFormatInfo;
+ DstFormatInfo: TAudioFormatInfo): TAudioConvertStream;
+begin
+ Result := TAudioConvertStream_SRC.Open(SrcFormatInfo, DstFormatInfo);
+end;
+
+{ TAudioConvertStream_SRC }
+
+constructor TAudioConvertStream_SRC.Create(SrcFormatInfo: TAudioFormatInfo;
+ DstFormatInfo: TAudioFormatInfo);
+begin
+ inherited Create(SrcFormatInfo, DstFormatInfo);
+end;
+
+destructor TAudioConvertStream_SRC.Destroy();
+begin
+ if (ConverterState <> nil) then
+ src_delete(ConverterState);
+ FormatConverter.Free;
+ inherited;
+end;
+
+class function TAudioConvertStream_SRC.Open(SrcFormatInfo: TAudioFormatInfo;
+ DstFormatInfo: TAudioFormatInfo): TAudioConvertStream_SRC;
+var
+ Stream: TAudioConvertStream_SRC;
+begin
+ Result := nil;
+ Stream := TAudioConvertStream_SRC.Create(SrcFormatInfo, DstFormatInfo);
+ if (not Stream.Init()) then
+ begin
+ Stream.Free;
+ Exit;
+ end;
+ Result := Stream;
+end;
+
+function TAudioConvertStream_SRC.Init(): boolean;
+var
+ error: integer;
+ TempSrcFormatInfo: TAudioFormatInfo;
+ TempDstFormatInfo: TAudioFormatInfo;
+begin
+ Result := false;
+
+ FormatConverter := nil;
+
+ // SRC does not handle channel or format conversion
+ if ((SrcFormatInfo.Channels <> DstFormatInfo.Channels) or
+ not (SrcFormatInfo.Format in [asfS16, asfFloat])) then
+ begin
+ // SDL can not convert to float, so we have to convert to SInt16 first
+ TempSrcFormatInfo := TAudioFormatInfo.Create(
+ SrcFormatInfo.Channels, SrcFormatInfo.SampleRate, SrcFormatInfo.Format);
+ TempDstFormatInfo := TAudioFormatInfo.Create(
+ DstFormatInfo.Channels, SrcFormatInfo.SampleRate, asfS16);
+
+ // init format/channel conversion
+ FormatConverter := TAudioConvertStream_SDL.Open(TempSrcFormatInfo, TempDstFormatInfo);
+
+ // this info was copied so we do not need it anymore
+ TempSrcFormatInfo.Free;
+ TempDstFormatInfo.Free;
+
+ // leave if the format is not supported
+ if (FormatConverter = nil) then
+ Exit;
+
+ // adjust our copy of the input audio-format for SRC conversion
+ Self.SrcFormatInfo.Channels := DstFormatInfo.Channels;
+ Self.SrcFormatInfo.Format := asfS16;
+ end;
+
+ if ((DstFormatInfo.Format <> asfS16) and
+ (DstFormatInfo.Format <> asfFloat)) then
+ begin
+ Log.LogError('Unsupported output format', 'TAudioConverter_SRC.Init');
+ Exit;
+ end;
+
+ ConversionData.src_ratio := DstFormatInfo.SampleRate / SrcFormatInfo.SampleRate;
+ if (src_is_valid_ratio(ConversionData.src_ratio) = 0) then
+ begin
+ Log.LogError('Invalid samplerate ratio', 'TAudioConverter_SRC.Init');
+ Exit;
+ end;
+
+ ConverterState := src_new(SRC_CONVERTER_TYPE, DstFormatInfo.Channels, @error);
+ if (ConverterState = nil) then
+ begin
+ Log.LogError('src_new() failed: ' + src_strerror(error), 'TAudioConverter_SRC.Init');
+ Exit;
+ end;
+
+ Result := true;
+end;
+
+function TAudioConvertStream_SRC.Convert(InputBuffer: PByteArray; OutputBuffer: PByteArray; var InputSize: integer): integer;
+var
+ FloatInputBuffer: PSingle;
+ FloatOutputBuffer: PSingle;
+ TempBuffer: PByteArray;
+ TempSize: integer;
+ NumSamples: integer;
+ OutputSize: integer;
+ error: integer;
+begin
+ Result := -1;
+
+ TempBuffer := nil;
+
+ // format conversion with external converter (to correct number of channels and format)
+ if (assigned(FormatConverter)) then
+ begin
+ TempSize := FormatConverter.GetOutputBufferSize(InputSize);
+ GetMem(TempBuffer, TempSize);
+ InputSize := FormatConverter.Convert(InputBuffer, TempBuffer, InputSize);
+ InputBuffer := TempBuffer;
+ end;
+
+ if (InputSize <= 0) then
+ begin
+ // avoid div-by-zero problems
+ if (InputSize = 0) then
+ Result := 0;
+ if (TempBuffer <> nil) then
+ FreeMem(TempBuffer);
+ Exit;
+ end;
+
+ if (SrcFormatInfo.Format = asfFloat) then
+ begin
+ FloatInputBuffer := PSingle(InputBuffer);
+ end else begin
+ NumSamples := InputSize div AudioSampleSize[SrcFormatInfo.Format];
+ GetMem(FloatInputBuffer, NumSamples * SizeOf(Single));
+ src_short_to_float_array(PCshort(InputBuffer), PCfloat(FloatInputBuffer), NumSamples);
+ end;
+
+ // calculate approx. output size
+ OutputSize := Ceil(InputSize * ConversionData.src_ratio);
+
+ if (DstFormatInfo.Format = asfFloat) then
+ begin
+ FloatOutputBuffer := PSingle(OutputBuffer);
+ end else begin
+ NumSamples := OutputSize div AudioSampleSize[DstFormatInfo.Format];
+ GetMem(FloatOutputBuffer, NumSamples * SizeOf(Single));
+ end;
+
+ with ConversionData do
+ begin
+ data_in := PCFloat(FloatInputBuffer);
+ input_frames := InputSize div SrcFormatInfo.FrameSize;
+ data_out := PCFloat(FloatOutputBuffer);
+ output_frames := OutputSize div DstFormatInfo.FrameSize;
+ // TODO: set this to 1 at end of file-playback
+ end_of_input := 0;
+ end;
+
+ error := src_process(ConverterState, @ConversionData);
+ if (error <> 0) then
+ begin
+ Log.LogError(src_strerror(error), 'TAudioConverter_SRC.Convert');
+ if (SrcFormatInfo.Format <> asfFloat) then
+ FreeMem(FloatInputBuffer);
+ if (DstFormatInfo.Format <> asfFloat) then
+ FreeMem(FloatOutputBuffer);
+ if (TempBuffer <> nil) then
+ FreeMem(TempBuffer);
+ Exit;
+ end;
+
+ if (SrcFormatInfo.Format <> asfFloat) then
+ FreeMem(FloatInputBuffer);
+
+ if (DstFormatInfo.Format <> asfFloat) then
+ begin
+ NumSamples := ConversionData.output_frames_gen * DstFormatInfo.Channels;
+ src_float_to_short_array(PCfloat(FloatOutputBuffer), PCshort(OutputBuffer), NumSamples);
+ FreeMem(FloatOutputBuffer);
+ end;
+
+ // free format conversion buffer if used
+ if (TempBuffer <> nil) then
+ FreeMem(TempBuffer);
+
+ if (assigned(FormatConverter)) then
+ InputSize := ConversionData.input_frames_used * FormatConverter.SrcFormatInfo.FrameSize
+ else
+ InputSize := ConversionData.input_frames_used * SrcFormatInfo.FrameSize;
+
+ // set result to output size according to SRC
+ Result := ConversionData.output_frames_gen * DstFormatInfo.FrameSize;
+end;
+
+function TAudioConvertStream_SRC.GetOutputBufferSize(InputSize: integer): integer;
+begin
+ Result := Ceil(InputSize * GetRatio());
+end;
+
+function TAudioConvertStream_SRC.GetRatio(): double;
+begin
+ // if we need additional channel/format conversion, use this ratio
+ if (assigned(FormatConverter)) then
+ Result := FormatConverter.GetRatio()
+ else
+ Result := 1.0;
+
+ // now the SRC ratio (Note: the format might change from SInt16 to float)
+ Result := Result *
+ ConversionData.src_ratio *
+ (DstFormatInfo.FrameSize / SrcFormatInfo.FrameSize);
+end;
+
+initialization
+ MediaManager.add(TAudioConverter_SRC.Create);
+
+end. \ No newline at end of file