Move audio decoding to separate method and fix incorrect decoding when there are...

diff --git a/src/lib/ffmpeg_decoder.cc b/src/lib/ffmpeg_decoder.cc
index 462db283ab8875dca384d96c045d44531513f4f7..ca019e06a9c5b1ea695aa87b436972b58b8a80d8 100644 (file)
--- a/src/lib/ffmpeg_decoder.cc
+++ b/src/lib/ffmpeg_decoder.cc
@@ -245,14 +245,7 @@ FFmpegDecoder::pass ()
                }
 
                if (_audio_stream && _opt.decode_audio) {
-                       while (avcodec_decode_audio4 (_audio_codec_context, _frame, &frame_finished, &_packet) >= 0 && frame_finished) {
-                               int const data_size = av_samples_get_buffer_size (
-                                       0, _audio_codec_context->channels, _frame->nb_samples, audio_sample_format (), 1
-                                       );
-
-                               assert (_audio_codec_context->channels == _film->audio_channels());
-                               Audio (deinterleave_audio (_frame->data, data_size));
-                       }
+                       decode_audio_packet ();
                }
 
                return true;
@@ -280,54 +273,7 @@ FFmpegDecoder::pass ()
                }
 
        } else if (ffa && _packet.stream_index == ffa->id() && _opt.decode_audio) {
-
-               int frame_finished;
-               if (avcodec_decode_audio4 (_audio_codec_context, _frame, &frame_finished, &_packet) >= 0 && frame_finished) {
-
-                       /* Where we are in the source, in seconds */
-                       double const source_pts_seconds = av_q2d (_format_context->streams[_packet.stream_index]->time_base)
-                               * av_frame_get_best_effort_timestamp(_frame);
-
-                       /* We only decode audio if we've had our first video packet through, and if it
-                          was before this packet.  Until then audio is thrown away.
-                       */
-                               
-                       if ((_first_video && _first_video.get() <= source_pts_seconds) || !_opt.decode_video) {
-
-                               if (!_first_audio && _opt.decode_video) {
-                                       _first_audio = source_pts_seconds;
-                                       
-                                       /* This is our first audio frame, and if we've arrived here we must have had our
-                                          first video frame.  Push some silence to make up any gap between our first
-                                          video frame and our first audio.
-                                       */
-                       
-                                       /* frames of silence that we must push */
-                                       int const s = rint ((_first_audio.get() - _first_video.get()) * ffa->sample_rate ());
-                                       
-                                       _film->log()->log (
-                                               String::compose (
-                                                       N_("First video at %1, first audio at %2, pushing %3 audio frames of silence for %4 channels (%5 bytes per sample)"),
-                                                       _first_video.get(), _first_audio.get(), s, ffa->channels(), bytes_per_audio_sample()
-                                                       )
-                                               );
-                                       
-                                       if (s) {
-                                               shared_ptr<AudioBuffers> audio (new AudioBuffers (ffa->channels(), s));
-                                               audio->make_silent ();
-                                               Audio (audio);
-                                       }
-                               }
-
-                               int const data_size = av_samples_get_buffer_size (
-                                       0, _audio_codec_context->channels, _frame->nb_samples, audio_sample_format (), 1
-                                       );
-                               
-                               assert (_audio_codec_context->channels == _film->audio_channels());
-                               Audio (deinterleave_audio (_frame->data, data_size));
-                       }
-               }
-                       
+               decode_audio_packet ();
        } else if (_subtitle_stream && _packet.stream_index == _subtitle_stream->id() && _opt.decode_subtitles && _first_video) {
 
                int got_subtitle;
@@ -744,3 +690,71 @@ FFmpegDecoder::frame_time () const
        return av_frame_get_best_effort_timestamp(_frame) * av_q2d (_format_context->streams[_video_stream]->time_base);
 }
 
+void
+FFmpegDecoder::decode_audio_packet ()
+{
+       shared_ptr<FFmpegAudioStream> ffa = dynamic_pointer_cast<FFmpegAudioStream> (_audio_stream);
+       assert (ffa);
+
+       /* Audio packets can contain multiple frames, so we may have to  call avcodec_decode_audio4
+          several times.
+       */
+       
+       AVPacket copy_packet = _packet;
+
+       while (copy_packet.size > 0) {
+
+               int frame_finished;
+               int const decode_result = avcodec_decode_audio4 (_audio_codec_context, _frame, &frame_finished, &copy_packet);
+               if (decode_result >= 0 && frame_finished) {
+                       
+                       /* Where we are in the source, in seconds */
+                       double const source_pts_seconds = av_q2d (_format_context->streams[copy_packet.stream_index]->time_base)
+                               * av_frame_get_best_effort_timestamp(_frame);
+                       
+                       /* We only decode audio if we've had our first video packet through, and if it
+                          was before this packet.  Until then audio is thrown away.
+                       */
+                       
+                       if ((_first_video && _first_video.get() <= source_pts_seconds) || !_opt.decode_video) {
+                               
+                               if (!_first_audio && _opt.decode_video) {
+                                       _first_audio = source_pts_seconds;
+                                       
+                                       /* This is our first audio frame, and if we've arrived here we must have had our
+                                          first video frame.  Push some silence to make up any gap between our first
+                                          video frame and our first audio.
+                                       */
+                                       
+                                       /* frames of silence that we must push */
+                                       int const s = rint ((_first_audio.get() - _first_video.get()) * ffa->sample_rate ());
+                                       
+                                       _film->log()->log (
+                                               String::compose (
+                                                       N_("First video at %1, first audio at %2, pushing %3 audio frames of silence for %4 channels (%5 bytes per sample)"),
+                                                       _first_video.get(), _first_audio.get(), s, ffa->channels(), bytes_per_audio_sample()
+                                                       )
+                                               );
+                                       
+                                       if (s) {
+                                               shared_ptr<AudioBuffers> audio (new AudioBuffers (ffa->channels(), s));
+                                               audio->make_silent ();
+                                               Audio (audio);
+                                       }
+                               }
+                               
+                               int const data_size = av_samples_get_buffer_size (
+                                       0, _audio_codec_context->channels, _frame->nb_samples, audio_sample_format (), 1
+                                       );
+                               
+                               assert (_audio_codec_context->channels == _film->audio_channels());
+                               Audio (deinterleave_audio (_frame->data, data_size));
+                       }
+               }
+
+               if (decode_result >= 0) {
+                       copy_packet.data += decode_result;
+                       copy_packet.size -= decode_result;
+               }
+       }
+}

diff --git a/src/lib/ffmpeg_decoder.h b/src/lib/ffmpeg_decoder.h
index c383b8d1325ef8eb82d8b20e16ddc2168a822407..1bb14ce9cfca0ea6d0ba2392c06b0e06b30725be 100644 (file)
--- a/src/lib/ffmpeg_decoder.h
+++ b/src/lib/ffmpeg_decoder.h
@@ -120,6 +120,8 @@ private:
        void setup_audio ();
        void setup_subtitle ();
 
+       void decode_audio_packet ();
+
        void maybe_add_subtitle ();
        boost::shared_ptr<AudioBuffers> deinterleave_audio (uint8_t** data, int size);