[FFmpeg-devel] [PATCH] lavfi: store and propagate number of channels information in audio buffer properties

[Stefano Sabatini]

The channels field is required since the channel layout is not always
available.
---
 libavfilter/af_ashowinfo.c |    3 ++-
 libavfilter/avcodec.c      |    2 ++
 libavfilter/avfilter.h     |    1 +
 3 files changed, 5 insertions(+), 1 deletions(-)

diff --git a/libavfilter/af_ashowinfo.c b/libavfilter/af_ashowinfo.c
index 0d4bbb2..65f18f5 100644
--- a/libavfilter/af_ashowinfo.c
+++ b/libavfilter/af_ashowinfo.c
@@ -66,12 +66,13 @@ static int filter_samples(AVFilterLink *inlink, AVFilterBufferRef *samplesref)
 
     av_log(ctx, AV_LOG_INFO,
            "n:%d pts:%s pts_time:%s pos:%"PRId64" "
-           "fmt:%s chlayout:%s nb_samples:%d rate:%d "
+           "fmt:%s channels:%d chlayout:%s nb_samples:%d rate:%d "
            "checksum:%08X plane_checksum[%08X",
            showinfo->frame,
            av_ts2str(samplesref->pts), av_ts2timestr(samplesref->pts, &inlink->time_base),
            samplesref->pos,
            av_get_sample_fmt_name(samplesref->format),
+           samplesref->audio->channels,
            chlayout_str,
            samplesref->audio->nb_samples,
            samplesref->audio->sample_rate,
diff --git a/libavfilter/avcodec.c b/libavfilter/avcodec.c
index f452303..8d61fbc 100644
--- a/libavfilter/avcodec.c
+++ b/libavfilter/avcodec.c
@@ -46,6 +46,7 @@ int avfilter_copy_frame_props(AVFilterBufferRef *dst, const AVFrame *src)
     case AVMEDIA_TYPE_AUDIO:
         dst->audio->sample_rate         = src->sample_rate;
         dst->audio->channel_layout      = src->channel_layout;
+        dst->audio->channels            = src->channels;
         break;
     default:
         return AVERROR(EINVAL);
@@ -137,6 +138,7 @@ int avfilter_copy_buf_props(AVFrame *dst, const AVFilterBufferRef *src)
         dst->nb_samples          = src->audio->nb_samples;
         av_frame_set_sample_rate   (dst, src->audio->sample_rate);
         av_frame_set_channel_layout(dst, src->audio->channel_layout);
+        av_frame_set_channels      (dst, src->audio->channels);
         break;
     default:
         return AVERROR(EINVAL);
diff --git a/libavfilter/avfilter.h b/libavfilter/avfilter.h
index 91820dd..c9ef7db 100644
--- a/libavfilter/avfilter.h
+++ b/libavfilter/avfilter.h
@@ -110,6 +110,7 @@ typedef struct AVFilterBuffer {
  */
 typedef struct AVFilterBufferRefAudioProps {
     uint64_t channel_layout;    ///< channel layout of audio buffer
+    int channels;               ///< number of channels
     int nb_samples;             ///< number of audio samples per channel
     int sample_rate;            ///< audio buffer sample rate
 } AVFilterBufferRefAudioProps;
-- 
1.7.5.4