fftools/ffmpeg: add muxer-input codec parameters to OutputStream

It stores codec parameters of the stream submitted to the muxer, which
may be different from the codec parameters in AVStream due to bitstream
filtering.

This avoids the confusing back and forth synchronisation between the
encoder, bitstream filters, and the muxer, now information flows only in
one direction. It also reduces the need for non-muxing code to access
AVStream.

1 files changed, 4 insertions, 2 deletions

diff --git a/fftools/ffmpeg_mux.c b/fftools/ffmpeg_mux.c
index eb64d8c3ff..40b439eea2 100644
--- a/fftools/ffmpeg_mux.c
+++ b/fftools/ffmpeg_mux.c
@@ -556,9 +556,9 @@ static int bsf_init(MuxStream *ms)
     int ret;
 
     if (!ctx)
-        return 0;
+        return avcodec_parameters_copy(ost->st->codecpar, ost->par_in);
 
-    ret = avcodec_parameters_copy(ctx->par_in, ost->st->codecpar);
+    ret = avcodec_parameters_copy(ctx->par_in, ost->par_in);
     if (ret < 0)
         return ret;
 
@@ -768,6 +768,8 @@ static void ost_free(OutputStream **post)
         av_fifo_freep2(&ms->muxing_queue);
     }
 
+    avcodec_parameters_free(&ost->par_in);
+
     av_bsf_free(&ms->bsf_ctx);
 
     av_frame_free(&ost->filtered_frame);