[FFmpeg-devel] [PATCH] fftools/ffmpeg_filter: at EOF, unref frame used for FPS conversion logic

[Steven Zhou]

fftools/ffmpeg_filter: at EOF, unref frame used for FPS conversion logic

Ever since commit 64f3feb added `avcodec_free_context(&enc->enc_ctx);` to
`enc_free()` the encoder context is closed before filtergraph output context. 
The filtergraph output context holds a reference to last AVFrame to pass through
it for FPS conversion purposes. This is problematic for HWFrameContexts which
may rely on encoder context to free HW AVFrames. This change unrefs the AVFrame
ref held by filtergraph output context during processing of EOF frame.

Signed-off-by: Steven Zhou <steven.zhou at netint.ca>
---
 fftools/ffmpeg_filter.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/fftools/ffmpeg_filter.c b/fftools/ffmpeg_filter.c
index a0dc4c745e..cf2d016b2d 100644
--- a/fftools/ffmpeg_filter.c
+++ b/fftools/ffmpeg_filter.c
@@ -2560,8 +2560,10 @@ static int fg_output_frame(OutputFilterPriv *ofp, FilterGraphThread *fgt,
         av_frame_move_ref(frame_prev, frame);
     }
 
-    if (!frame)
+    if (!frame) {
+        av_frame_unref(frame_prev);
         return close_output(ofp, fgt);
+    }
 
     return 0;
 }
-- 
2.25.1