> On 07/05/2023 2:16 PM CDT James Zern <jzern-at-google....@ffmpeg.org> wrote: > > > On Wed, Jul 5, 2023 at 12:15 PM James Zern <jz...@google.com> wrote: > > > > Hi, > > > > +ffmpeg-dev. I took the wrong email off the reply. > > > On Mon, Jul 3, 2023 at 10:08 PM David Lemler <david@lemler.family> wrote: > > > > > > Prevent the fifo used in encoding VPx videos from filling up and stopping > > > encode when it reaches 21845 items, which happens when the video has more > > > than > > > that number of frames. > > > > > > > What failure do you see, a memory allocation error? 21845 sounds > > somewhat arbitrary, maybe specific to your machine, so I'd leave it > > off the comment and commit message. > >
When running a command like the following to perform the first pass of a 2-pass VP9 encode: ffmpeg -i input.mp4 -c:v libvpx-vp9 -b:v 0 -crf 31 -pass 1 -an \ -deadline best -threads 8 -row-mt 1 -f null /dev/null ffmpeg exited with the error: Error submitting video frame to the encoder Conversion failed! and the ffmpeg2pass-0.log file existed but was empty. I've tested and reproduced the issue on Intel x86-64 on Windows (10 22H2, gyan.dev build) and Linux (Debian 12, own compiled build), and on AMD EPYC x86-64 on Linux (Debian 12, own compiled build). I believe the number of frames is (1024 * 1024) / sizeof(FrameData); see lavc/libvpxenc.c the call to av_fifo_alloc2 around line 999 and lavutil/fifo.c the assignment of f->auto_grow_limit around line 72. I'm not sure if that calculation would change on different systems/architectures. During testing, I added a debug log below the can_grow assignment ternary in fifo_check_space in lavutil/fifo.c logging out the values of need_grow, can_grow, f->auto_grow_limit, and f->nb_elems and noticed that as the encode was happening, the nb_elems value kept increasing and can_grow kept decreasing until nb_elems got to f->auto_grow_limit and can_grow to 0, at which point the encode failed with the error mentioned previously. This is the first time I've contributed to FFmpeg (or a project that uses a mailing list), so I'm still becoming familiar with standard practices for commit formatting and development. If that value is dependent on variables like compiler or architecture or you otherwise think I should remove it, let me know and I'll re-submit a modified patch. > > > This problem occurs when performing the first pass of a 2-pass encode, as > > > otherwise, the fifo is properly drained, preventing it from overflowing. > > > > > > Problem is fixed by manually draining the fifo when performing the first > > > pass > > > of a 2-pass encode. > > > > > > Fixes the regression originally introduced in > > > 5bda4ec6c3cb6f286bb40dee4457c3c26e0f78cb > > > > > > > Anton, any comments here? > > > > > Signed-off-by: David Lemler <david@lemler.family> > > > --- > > > libavcodec/libvpxenc.c | 6 ++++++ > > > 1 file changed, 6 insertions(+) > > > > > > diff --git a/libavcodec/libvpxenc.c b/libavcodec/libvpxenc.c > > > index 8833df2d68..e4ab13e6ab 100644 > > > --- a/libavcodec/libvpxenc.c > > > +++ b/libavcodec/libvpxenc.c > > > @@ -1452,6 +1452,12 @@ static int queue_frames(AVCodecContext *avctx, > > > struct > > > vpx_codec_ctx *encoder, > > > memcpy((uint8_t*)stats->buf + stats->sz, > > > pkt->data.twopass_stats.buf, > > > pkt->data.twopass_stats.sz); > > > stats->sz += pkt->data.twopass_stats.sz; > > > + /* Drain the fifo if it has any items in it to prevent it > > > from > > > + filling up when performing the first pass of a 2-pass > > > encode > > > if > > > + the video has more than 21845 frames. */ > > > + if (av_fifo_can_read(ctx->fifo) > 0) { > > > > Another option would be to avoid calling frame_data_submit() in the first > > pass. > > > > > + av_fifo_drain2(ctx->fifo, 1); > > > + } > > > break; > > > } > > > case VPX_CODEC_PSNR_PKT: > > > -- > > > 2.41.0.windows.1 > > > _______________________________________________ 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".