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Clement Champetier
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Add AudioTransform: convert samples
* AudioTransform: does the same process as ColorTransform, but applied to audio. * AudioDesc: add a function to get a FrameDesc. * AudioRewrapper: use AudioTransform.
1 parent 3a719d0 commit 36de2c6

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6 files changed

+156
-22
lines changed

6 files changed

+156
-22
lines changed

‎app/SConscript

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Original file line numberDiff line numberDiff line change
@@ -69,6 +69,7 @@ audioRewrapper = env.Program(
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'avformat',
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'avcodec',
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'swscale',
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'swresample',
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]
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)
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‎app/audioRewrapper/audioRewrapper.cpp

Lines changed: 35 additions & 22 deletions
Original file line numberDiff line numberDiff line change
@@ -2,11 +2,15 @@
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#include <iomanip>
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#include <AvTranscoder/InputFile.hpp>
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#include <AvTranscoder/OutputFile.hpp>
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#include <AvTranscoder/AvInputStream.hpp>
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#include <AvTranscoder/InputStreamAudio.hpp>
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#include <AvTranscoder/OutputStreamAudio.hpp>
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9-
#include <AvTranscoder/OutputFile.hpp>
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#include <AvTranscoder/AudioTransform.hpp>
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void rewrapAudio( const char* inputfilename, const char* outputFilename )
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{
@@ -52,56 +56,65 @@ void transcodeAudio( const char* inputfilename, const char* outputFilename )
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InputFile inputFile( inputfilename );
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inputFile.analyse();
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59+
OutputFile outputFile( outputFilename );
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outputFile.setup();
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// init audio decoders
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InputStreamAudio inputStreamAudio( inputFile.getStream( 0 ) );
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inputFile.getStream( 0 ).setBufferred( true );
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OutputFile outputFile( outputFilename );
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outputFile.setup();
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outputFile.addAudioStream( inputFile.getStream( 0 ).getAudioDesc() );
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outputFile.beginWrap();
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66+
// init audio encoders
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OutputStreamAudio outputStreamAudio;
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AudioDesc& audioDesc = outputStreamAudio.getAudioDesc();
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audioDesc.setAudioCodec( "pcm_s16le" );
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audioDesc.setAudioCodec( "pcm_s24le" );
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audioDesc.setAudioParameters(
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inputFile.getStream( 0 ).getAudioDesc().getSampleRate(),
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inputFile.getStream( 0 ).getAudioDesc().getChannels(),
70-
inputFile.getStream( 0 ).getAudioDesc().getSampleFormat()
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AV_SAMPLE_FMT_S32//,inputFile.getStream( 0 ).getAudioDesc().getSampleFormat()
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);
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73-
DataStream codedFrame;
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if( ! outputStreamAudio.setup( ) )
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{
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std::cout << "error during initialising audio output stream" << std::endl;
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exit( -1 );
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}
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81-
// Transcoding
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std::cout << "start transcoding" << std::endl;
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outputFile.addAudioStream( audioDesc );
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outputFile.beginWrap();
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// init convert
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AudioTransform audioTransform;
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DataStream codedFrame;
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90+
// start transcoding process
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std::cout << "start transcoding" << std::endl;
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AudioFrame audioFrameSource( inputFile.getStream( 0 ).getAudioDesc().getFrameDesc() );
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AudioFrame audioFrameToEncode( audioDesc.getFrameDesc() );
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8496
size_t frame = 0;
85-
AudioFrameDesc audioFrameDesc;
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AudioFrame audioFrame( audioFrameDesc );
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while( inputStreamAudio.readNextFrame( audioFrame ) )
97+
while( inputStreamAudio.readNextFrame( audioFrameSource ) )
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{
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std::cout << "\rprocess frame " << (int)frame - 1 << std::endl << std::flush;
99+
std::cout << "\rprocess frame " << (int)frame - 1 << std::flush;
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93-
// convert
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outputStreamAudio.encodeFrame( audioFrame, codedFrame );
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audioTransform.convert( audioFrameSource, audioFrameToEncode );
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103+
outputStreamAudio.encodeFrame( audioFrameToEncode, codedFrame );
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outputFile.wrap( codedFrame, 0 );
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++frame;
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// if(frame == 10*48100)
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// break;
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}
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std::cout << std::endl;
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outputStreamAudio.encodeFrame( codedFrame );
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outputFile.wrap( codedFrame, 0 );
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// end of transcoding process
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outputFile.endWrap();
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}
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‎src/AvTranscoder/AudioTransform.cpp

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,74 @@
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#include "AudioTransform.hpp"
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#include "DatasStructures/AudioFrame.hpp"
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#include "common.hpp"
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extern "C" {
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#ifndef __STDC_CONSTANT_MACROS
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#define __STDC_CONSTANT_MACROS
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#endif
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#include <libavcodec/avcodec.h>
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#include <libavutil/opt.h>
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#include <libswresample/swresample.h>
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#if LIBAVCODEC_VERSION_MAJOR > 54
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#include <libavutil/frame.h>
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#endif
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}
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#include <stdexcept>
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namespace avtranscoder
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{
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AudioTransform::AudioTransform()
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: m_audioConvertContext( NULL )
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, m_isInit ( false )
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{
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}
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bool AudioTransform::init( const AudioFrame& src, const AudioFrame& dst )
29+
{
30+
m_audioConvertContext = swr_alloc();
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if( !m_audioConvertContext )
33+
{
34+
throw std::runtime_error( "unable to create audio convert context" );
35+
}
36+
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av_opt_set_int(m_audioConvertContext, "in_channel_layout", av_get_default_channel_layout( src.desc().getChannels() ), 0);
38+
av_opt_set_int(m_audioConvertContext, "out_channel_layout", av_get_default_channel_layout( dst.desc().getChannels() ), 0);
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av_opt_set_int(m_audioConvertContext, "in_sample_rate", src.desc().getSampleRate(), 0);
41+
av_opt_set_int(m_audioConvertContext, "out_sample_rate", dst.desc().getSampleRate(), 0);
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43+
av_opt_set_int(m_audioConvertContext, "in_sample_fmt", src.desc().getSampleFormat(), 0);
44+
av_opt_set_int(m_audioConvertContext, "out_sample_fmt", dst.desc().getSampleFormat(), 0);
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46+
if( swr_init( m_audioConvertContext ) < 0 )
47+
{
48+
swr_free( &m_audioConvertContext );
49+
throw std::runtime_error( "unable to open audio convert context" );
50+
}
51+
52+
return true;
53+
}
54+
55+
void AudioTransform::convert( const AudioFrame& src, AudioFrame& dst )
56+
{
57+
if( ! m_isInit )
58+
{
59+
m_isInit = init( src, dst );
60+
m_isInit = true;
61+
}
62+
63+
if( dst.getSize() != src.getSize() )
64+
dst.getBuffer().resize( src.getSize(), 0 );
65+
66+
const unsigned char* srcData = src.getPtr();
67+
unsigned char* dstData = dst.getPtr();
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69+
swr_convert( m_audioConvertContext, &dstData, dst.getSize(), &srcData, src.getSize() );
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71+
dst.setNbSamples( src.getNbSamples() );
72+
}
73+
74+
}

‎src/AvTranscoder/AudioTransform.hpp

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@@ -0,0 +1,30 @@
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#ifndef _AV_TRANSCODER_AUDIO_TRANSFORM_HPP
2+
#define _AV_TRANSCODER_AUDIO_TRANSFORM_HPP
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4+
#include "common.hpp"
5+
6+
class SwrContext;
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8+
namespace avtranscoder
9+
{
10+
11+
class AudioFrame;
12+
13+
class AvExport AudioTransform
14+
{
15+
public:
16+
AudioTransform();
17+
18+
void convert( const AudioFrame& src, AudioFrame& dst );
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20+
private:
21+
bool init( const AudioFrame& src, const AudioFrame& dst );
22+
23+
SwrContext* m_audioConvertContext;
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25+
bool m_isInit;
26+
};
27+
28+
}
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30+
#endif

‎src/AvTranscoder/DatasStructures/AudioDesc.cpp

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@@ -1,4 +1,5 @@
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#include "AudioDesc.hpp"
2+
#include "AudioFrame.hpp"
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34
extern "C" {
45
#ifndef __STDC_CONSTANT_MACROS
@@ -209,5 +210,16 @@ const AVSampleFormat AudioDesc::getSampleFormat() const
209210
return m_codecContext->sample_fmt;
210211
}
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213+
AudioFrameDesc AudioDesc::getFrameDesc() const
214+
{
215+
AudioFrameDesc audioFrameDesc;
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217+
audioFrameDesc.setChannels( m_codecContext->channels );
218+
audioFrameDesc.setSampleRate( m_codecContext->sample_rate );
219+
audioFrameDesc.setSampleFormat( m_codecContext->sample_fmt );
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221+
return audioFrameDesc;
222+
}
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}

‎src/AvTranscoder/DatasStructures/AudioDesc.hpp

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@@ -18,6 +18,8 @@ extern "C" {
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namespace avtranscoder
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{
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class AudioFrameDesc;
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2123
class AvExport AudioDesc
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{
2325
public:
@@ -48,6 +50,8 @@ class AvExport AudioDesc
4850
AVCodecContext* getCodecContext() const { return m_codecContext; }
4951
#endif
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53+
AudioFrameDesc getFrameDesc() const;
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private:
5256
void initCodecContext( );
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