On Thu, 19. Aug 16:55, Ming Qian wrote: > client need to resume the decoding process > after it dequeues the source change event. > no matter what's the return value of v4l2_resolution_changed(). > if the client doesn't resume the decoding process, > the decoder may keep waiting > > in documentation of v4l2 stateful decoder, we can see the following > description: > The client must continue the sequence as described below to > continue the decoding process. > 1. Dequeue the source change event. > Important > A source change triggers an implicit decoder drain, > similar to the explicit Drain sequence. The decoder is > stopped after it completes. The decoding process must be > resumed with either a pair of calls to > VIDIOC_STREAMOFF() and VIDIOC_STREAMON() on the CAPTURE > queue, or a call to VIDIOC_DECODER_CMD() with the > V4L2_DEC_CMD_START command. > 2. Continue with the Capture Setup sequence.
Please also add that this fixes decoding of https://streams.videolan.org/ffmpeg/incoming/720p60.mp4 on RPi4. > > Signed-off-by: Ming Qian <ming.q...@nxp.com> > --- > libavcodec/v4l2_context.c | 52 ++++++++++++++++++++++++--------------- > 1 file changed, 32 insertions(+), 20 deletions(-) > > diff --git a/libavcodec/v4l2_context.c b/libavcodec/v4l2_context.c > index dda5157698c3..b08f0015c2e5 100644 > --- a/libavcodec/v4l2_context.c > +++ b/libavcodec/v4l2_context.c > @@ -153,6 +153,21 @@ static inline void v4l2_save_to_context(V4L2Context* > ctx, struct v4l2_format_upd > } > } > > +static int v4l2_start_decode(V4L2Context *ctx) > +{ > + struct v4l2_decoder_cmd cmd = { > + .cmd = V4L2_DEC_CMD_START, > + .flags = 0, > + }; > + int ret; > + > + ret = ioctl(ctx_to_m2mctx(ctx)->fd, VIDIOC_DECODER_CMD, &cmd); > + if (ret) > + return AVERROR(errno); > + > + return 0; > +} > + > /** > * handle resolution change event and end of stream event > * returns 1 if reinit was successful, negative if it failed > @@ -163,7 +178,7 @@ static int v4l2_handle_event(V4L2Context *ctx) > V4L2m2mContext *s = ctx_to_m2mctx(ctx); > struct v4l2_format cap_fmt = s->capture.format; > struct v4l2_event evt = { 0 }; > - int reinit, ret; > + int ret; > > ret = ioctl(s->fd, VIDIOC_DQEVENT, &evt); > if (ret < 0) { > @@ -185,35 +200,29 @@ static int v4l2_handle_event(V4L2Context *ctx) > return 0; > } > > - reinit = v4l2_resolution_changed(&s->capture, &cap_fmt); > - if (reinit) { > + if (v4l2_resolution_changed(&s->capture, &cap_fmt)) { > s->capture.height = v4l2_get_height(&cap_fmt); > s->capture.width = v4l2_get_width(&cap_fmt); > s->capture.sample_aspect_ratio = v4l2_get_sar(&s->capture); > + } else { > + v4l2_start_decode(ctx); > + return 0; > } You can minimize the diff just by adding this part and the definition for v4l2_start_decode(). Then have a separate commit that cleans up and removes the reinit variable. > > - if (reinit) > - s->reinit = 1; > + s->reinit = 1; > > - if (reinit) { > - if (s->avctx) > - ret = ff_set_dimensions(s->avctx, s->capture.width, > s->capture.height); > - if (ret < 0) > - av_log(logger(ctx), AV_LOG_WARNING, "update avcodec height and > width\n"); > + if (s->avctx) > + ret = ff_set_dimensions(s->avctx, s->capture.width, > s->capture.height); > + if (ret < 0) > + av_log(logger(ctx), AV_LOG_WARNING, "update avcodec height and > width\n"); > > - ret = ff_v4l2_m2m_codec_reinit(s); > - if (ret) { > - av_log(logger(ctx), AV_LOG_ERROR, "v4l2_m2m_codec_reinit\n"); > - return AVERROR(EINVAL); > - } > - goto reinit_run; > + ret = ff_v4l2_m2m_codec_reinit(s); > + if (ret) { > + av_log(logger(ctx), AV_LOG_ERROR, "v4l2_m2m_codec_reinit\n"); > + return AVERROR(EINVAL); > } > > - /* dummy event received */ > - return 0; > - > /* reinit executed */ > -reinit_run: > return 1; > } > > @@ -551,6 +560,9 @@ int ff_v4l2_context_set_status(V4L2Context* ctx, uint32_t > cmd) > int type = ctx->type; > int ret; > > + if (ctx->streamon == (cmd == VIDIOC_STREAMON)) > + return 0; > + This change looks unrelated. > ret = ioctl(ctx_to_m2mctx(ctx)->fd, cmd, &type); > if (ret < 0) > return AVERROR(errno); Thanks, -- Andriy _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
