waveform display

[kdenlive] / src / renderer.cpp

diff --git a/src/renderer.cpp b/src/renderer.cpp
index 600dcfad33af019b04cb9509272e52c0723828e8..80ae7c38cd97792af94b12325210b0dd0edbcd39 100644 (file)
--- a/src/renderer.cpp
+++ b/src/renderer.cpp
@@ -64,7 +64,7 @@ static void consumer_frame_show(mlt_consumer, Render * self, mlt_frame frame_ptr
 #ifdef Q_WS_MAC
     self->showFrame(frame);
 #endif
-
+       self->showAudio(frame);
     self->emitFrameNumber(mlt_frame_get_position(frame_ptr));
     if (self->sendFrameForAnalysis && frame_ptr->convert_image) {
         self->emitFrameUpdated(frame);
@@ -1493,6 +1493,47 @@ void Render::showFrame(Mlt::Frame& frame)
 }
 #endif
 
+void Render::showAudio(Mlt::Frame& frame)
+{
+       mlt_audio_format audio_format=mlt_audio_pcm;
+       int freq,num_channels,samples;
+       uint8_t* data=(uint8_t*)frame.get_audio(audio_format,freq,num_channels,samples);
+       if (!data)
+               return;
+       int value=0;
+       QByteArray channels;
+
+       for (int i=0;i<num_channels;i++){
+       /*      switch (audio_format)
+               {
+                       case 0:
+                               value=( ( (uint8_t*)data) [i]   );
+                               break;
+                       case 1:
+                               value=( ( (uint16_t*)data) [i]  >> 8 );
+                               break;
+                       case 2:
+                               value=( ((uint32_t*)data) [i] >> 16 );
+                               break;
+                       case 3:
+                               value=( ((float*)data) [i]*255);
+                               break;
+                       default:
+                               value=0;
+               }
+               */
+               long val=0;
+               int num_samples=20;
+               for (int s=0;s<samples;s+=samples/num_samples){
+                       val+=(data[i+s*num_channels]- 127);
+               }
+               channels.append(val/num_samples);
+       }
+
+
+       if (samples>0)
+               emit showAudioSignal(channels);
+}
 
 /*
  * MLT playlist direct manipulation.