From 80c8c05457d1a7ba37a15b7150e6797dd4dac8e1 Mon Sep 17 00:00:00 2001 From: Seungha Yang Date: Thu, 24 Oct 2019 00:25:28 +0900 Subject: [PATCH] avviddec: Enforce allocate new AVFrame per input frame ... if ffmpeg would reuse the allocated AVBuffer. Reused AVFrame by the ffmpeg seems to break our decoding flow since the reused AVFrame holds the initial opaque data (GstVideoCodecFrame in this case), so we couldn't trace the our in/out frames. To enforce get_buffer() call per output frame, hold another reference to the AVBuffer in order to mark the AVBuffer as not writable. Fixes: https://gitlab.freedesktop.org/gstreamer/gst-libav/issues/62 --- ext/libav/gstavviddec.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/ext/libav/gstavviddec.c b/ext/libav/gstavviddec.c index d544567f88..f04a33864f 100644 --- a/ext/libav/gstavviddec.c +++ b/ext/libav/gstavviddec.c @@ -773,6 +773,12 @@ gst_ffmpegviddec_can_direct_render (GstFFMpegVidDec * ffmpegdec) AV_CODEC_CAP_DR1); } +static void +gst_ffmpegviddec_avbuffer_unref (AVBufferRef * avbuffer) +{ + av_buffer_unref (&avbuffer); +} + /* called when ffmpeg wants us to allocate a buffer to write the decoded frame * into. We try to give it memory from our pool */ static int @@ -866,6 +872,16 @@ gst_ffmpegviddec_get_buffer2 (AVCodecContext * context, AVFrame * picture, } picture->buf[0] = av_buffer_create (NULL, 0, dummy_free_buffer, dframe, 0); + if ((flags & AV_GET_BUFFER_FLAG_REF) == AV_GET_BUFFER_FLAG_REF) { + /* decoder might reuse this AVFrame and it would result to no more + * get_buffer() call if the AVFrame's AVBuffer is writable + * (meaning that the refcount of AVBuffer == 1). + * To enforce get_buffer() for the every output frame, hold another ref here + */ + gst_video_codec_frame_set_user_data (frame, + av_buffer_ref (picture->buf[0]), + (GDestroyNotify) gst_ffmpegviddec_avbuffer_unref); + } GST_LOG_OBJECT (ffmpegdec, "returned frame %p", dframe->buffer);