Fix: compensate codec latency in positive offset

.gitignore

@@ -12,8 +12,10 @@
 *.la
 *.a
 
-build
+build*
 dist
+install*
+test/**/test*[.wav|.avi|.mov|.h264|.mxf]
 
 # CMake
 CMakeCache.txt

src/AvTranscoder/decoder/AudioDecoder.cpp

@@ -121,6 +121,10 @@ bool AudioDecoder::decodeNextFrame(IFrame& frameBuffer)
             return false;
         }
     }
+
+    if(decodeNextFrame)
+        incrementNbDecodedFrames(frameBuffer.getAVFrame().nb_samples);
+
     return decodeNextFrame;
 }
 

src/AvTranscoder/decoder/AudioGenerator.cpp

@@ -58,6 +58,8 @@ bool AudioGenerator::decodeNextFrame(IFrame& frameBuffer)
         LOG_DEBUG("Convert data of the audio specified when decode next frame")
         _audioTransform.convert(*_inputFrame, frameBuffer);
     }
+
+    incrementNbDecodedFrames(_silent->getNbSamplesPerChannel());
     return true;
 }
 

src/AvTranscoder/decoder/IDecoder.hpp

@@ -10,7 +10,16 @@ namespace avtranscoder
 
 class AvExport IDecoder
 {
+protected:
+    IDecoder()
+        : _decoded_frames_counter(0)
+    {
+    }
+
 public:
+
+
+
     virtual ~IDecoder(){};
 
     /**
@@ -51,6 +60,16 @@ class AvExport IDecoder
      * @note Not sense for generators.
      */
     virtual void flushDecoder() {}
+
+    size_t getNbDecodedFrames() { return _decoded_frames_counter; }
+
+protected:
+    void incrementNbDecodedFrames(const size_t& nb_frames = 1) {
+        _decoded_frames_counter += nb_frames;
+    }
+
+private:
+    size_t _decoded_frames_counter;
 };
 }
 

src/AvTranscoder/decoder/VideoDecoder.cpp

@@ -114,6 +114,10 @@ bool VideoDecoder::decodeNextFrame(IFrame& frameBuffer)
             return false;
         }
     }
+
+    if(decodeNextFrame)
+        incrementNbDecodedFrames();
+
     return decodeNextFrame;
 }
 

src/AvTranscoder/decoder/VideoGenerator.cpp

@@ -51,6 +51,8 @@ bool VideoGenerator::decodeNextFrame(IFrame& frameBuffer)
         LOG_DEBUG("Convert data of the image specified when decode next frame")
         _videoTransform.convert(*_inputFrame, frameBuffer);
     }
+
+    incrementNbDecodedFrames();
     return true;
 }
 

src/AvTranscoder/transcoder/StreamTranscoder.cpp

@@ -617,7 +617,20 @@ bool StreamTranscoder::processFrame()
     // Manage offset
     if(_offset > 0)
     {
-        const bool endOfOffset = _outputStream->getStreamDuration() >= _offset;
+        bool endOfOffset = false;
+        if(_currentDecoder == _generators.at(0))
+        {
+            const double fps = 1.0 * _outputEncoder->getCodec().getAVCodecContext().time_base.den /
+                (_outputEncoder->getCodec().getAVCodecContext().time_base.num * _outputEncoder->getCodec().getAVCodecContext().ticks_per_frame);
+            const double frame_duration = 1.0 / fps;
+            const double generated_duration = _currentDecoder->getNbDecodedFrames() * frame_duration;
+            endOfOffset = generated_duration >= _offset;
+        }
+        else
+        {
+            endOfOffset = _outputStream->getStreamDuration() >= _offset;
+        }
+
         if(endOfOffset)
         {
             LOG_INFO("End of positive offset")
@@ -704,6 +717,7 @@ bool StreamTranscoder::processTranscode()
     assert(_outputEncoder != NULL);
     assert(! _decodedData.empty());
     assert(_transform != NULL);
+    assert(_generators.size() == _inputDecoders.size());
 
     LOG_DEBUG("StreamTranscoder::processTranscode")
 
@@ -750,8 +764,7 @@ bool StreamTranscoder::processTranscode()
         }
     }
 
-    // Transform
-    CodedData data;
+    // Check decoding status
     bool continueProcess = true;
     for(size_t index = 0; index < decodingStatus.size(); ++index)
     {
@@ -760,6 +773,17 @@ bool StreamTranscoder::processTranscode()
             if(!_filterGraph->hasFilters() || !_filterGraph->hasBufferedFrames(index))
             {
                 continueProcess = false;
+                if(_needToSwitchToGenerator)
+                {
+                    switchToGeneratorDecoder();
+                    LOG_INFO("Force reallocation of the decoded data buffers since the decoders could have cleared them.")
+                    for(std::vector<IFrame*>::iterator it = _decodedData.begin(); it != _decodedData.end(); ++it)
+                    {
+                        if(! (*it)->isDataAllocated())
+                            (*it)->allocateData();
+                    }
+                    return processTranscode();
+                }
                 break;
             }
             LOG_DEBUG("Some frames remain into filter graph buffer " << index);
@@ -771,8 +795,10 @@ bool StreamTranscoder::processTranscode()
         }
     }
 
+    CodedData data;
     if(continueProcess)
     {
+        // Transform
         IFrame* dataToTransform = NULL;
         if(_filterGraph->hasFilters())
         {