Fix checking of frame channels vs stream channels.

The comment says that we're handling differences between channel
counts in the frame and stream but the code wasn't doing that.

2 files changed, 6 insertions, 7 deletions

diff --git a/src/lib/ffmpeg_decoder.cc b/src/lib/ffmpeg_decoder.cc
index ba96d71ff..a5b36d04f 100644
--- a/src/lib/ffmpeg_decoder.cc
+++ b/src/lib/ffmpeg_decoder.cc
@@ -219,8 +219,9 @@ FFmpegDecoder::pass ()
 /** @param data pointer to array of pointers to buffers.
  *  Only the first buffer will be used for non-planar data, otherwise there will be one per channel.
  */
+static
 shared_ptr<AudioBuffers>
-FFmpegDecoder::deinterleave_audio (AVFrame* frame)
+deinterleave_audio(shared_ptr<FFmpegAudioStream> stream, AVFrame* frame)
 {
 	auto format = static_cast<AVSampleFormat>(frame->format);
 
@@ -326,12 +327,12 @@ FFmpegDecoder::deinterleave_audio (AVFrame* frame)
 	case AV_SAMPLE_FMT_FLTP:
 	{
 		auto p = reinterpret_cast<float**> (frame->data);
-		DCPOMATIC_ASSERT (frame->channels <= channels);
+		DCPOMATIC_ASSERT(channels <= stream->channels());
 		/* Sometimes there aren't as many channels in the frame as in the stream */
-		for (int i = 0; i < frame->channels; ++i) {
+		for (int i = 0; i < channels; ++i) {
 			memcpy (data[i], p[i], frames * sizeof(float));
 		}
-		for (int i = frame->channels; i < channels; ++i) {
+		for (int i = channels; i < stream->channels(); ++i) {
 			audio->make_silent (i);
 		}
 	}
@@ -450,7 +451,7 @@ void
 FFmpegDecoder::process_audio_frame (shared_ptr<FFmpegAudioStream> stream)
 {
 	auto frame = audio_frame (stream);
-	auto data = deinterleave_audio (frame);
+	auto data = deinterleave_audio(stream, frame);
 
 	auto const time_base = stream->stream(_format_context)->time_base;
 
diff --git a/src/lib/ffmpeg_decoder.h b/src/lib/ffmpeg_decoder.h
index ce2476fb0..e1a023453 100644
--- a/src/lib/ffmpeg_decoder.h
+++ b/src/lib/ffmpeg_decoder.h
@@ -59,8 +59,6 @@ private:
 
 	bool flush ();
 
-	static std::shared_ptr<AudioBuffers> deinterleave_audio (AVFrame* frame);
-
 	AVSampleFormat audio_sample_format (std::shared_ptr<FFmpegAudioStream> stream) const;
 	int bytes_per_audio_sample (std::shared_ptr<FFmpegAudioStream> stream) const;