Hi Gyan, On Sun, Jul 18, 2021 at 12:24 PM Gyan Doshi <ffm...@gyani.pro> wrote: > > > > On 2021-07-18 09:32, Linjie Fu wrote: > > On Wed, Jul 7, 2021 at 9:42 AM Linjie Fu <linjie.justin...@gmail.com> wrote: > >> On Sun, Jul 4, 2021 at 10:50 PM Linjie Fu <fulin...@zju.edu.cn> wrote: > >>> From: Linjie Fu <linjie.justin...@gmail.com> > >>> > >>> Skip the logic of frame rate emulation until the input reaches the > >>> specified start time. > >>> > >>> Test CMD: > >>> $ffmpeg -re -ss 30 -i input.mp4 -pix_fmt yuv420p -f sdl2 - > >>> > >>> Before the patch: > >>> first time to got frame, it takes 257305 us > >>> After this patch: > >>> first time to got frame, it takes 48879 us > >>> > >>> Signed-off-by: Linjie Fu <linjie.justin...@gmail.com> > >>> --- > >>> [v2]: fixed the mixed declaration and code warning > >>> Calculate the time to get the first frame: > >>> https://github.com/fulinjie/ffmpeg/commit/2aa4762e1e65709997b1ab9dd596332244db80ed > >>> fftools/ffmpeg.c | 8 ++++++-- > >>> 1 file changed, 6 insertions(+), 2 deletions(-) > >>> > >>> diff --git a/fftools/ffmpeg.c b/fftools/ffmpeg.c > >>> index e97d879cb3..c8849e4250 100644 > >>> --- a/fftools/ffmpeg.c > >>> +++ b/fftools/ffmpeg.c > >>> @@ -4221,10 +4221,14 @@ static int get_input_packet(InputFile *f, > >>> AVPacket **pkt) > >>> { > >>> if (f->rate_emu) { > >>> int i; > >>> + int64_t pts; > >>> + int64_t now; > >>> for (i = 0; i < f->nb_streams; i++) { > >>> InputStream *ist = input_streams[f->ist_index + i]; > >>> - int64_t pts = av_rescale(ist->dts, 1000000, AV_TIME_BASE); > >>> - int64_t now = av_gettime_relative() - ist->start; > >>> + if (!ist->got_output) > >>> + continue; > >>> + pts = av_rescale(ist->dts, 1000000, AV_TIME_BASE); > >>> + now = av_gettime_relative() - ist->start; > >>> if (pts > now) > >>> return AVERROR(EAGAIN); > >>> } > >>> -- > >>> 2.31.1 > >> ping, thx. > >> > > Another ping, thx. > > I pushed changes to this code yesterday. I don't think it's required > anymore, but do test. >
Thanks for the review, tested after applying the readrate patch, I'm afraid that it's not identical as hope, since ist->nb_packets would increase no matter input stream got output or not: (lldb) p ist->nb_packets (uint64_t) $4 = 1 (lldb) p ist->got_output (int) $5 = 0 Hence we still need to add the check for ist->got_output, or replace the ist->nb_packets. Also there is a new warning caught by the check in patchwork, probably "mixed declaration and code warning". Will send patches to rebase and fix. - linjie _______________________________________________ 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".
