On Wed, Oct 23, 2019 at 02:32:54PM +0200, Marton Balint wrote: > > > On Wed, 23 Oct 2019, Limin Wang wrote: > > > > > > >ping, it's another approach to discard frozen frame, please comments. > > > > > >On Thu, Oct 10, 2019 at 11:48:40AM +0800, lance.lmw...@gmail.com wrote: > >>From: Limin Wang <lance.lmw...@gmail.com> > >> > >>As suggested by Paul to support frozen frames discard, please refer to: > >>https://patchwork.ffmpeg.org/patch/15423/ > >> > >>You can tested with below commands: > >> > >>./ffmpeg -f lavfi -i > >>"smptebars=duration=5:size=1280x720:rate=30,freezedetect,metadata=mode=select:key=lavfi.freezedetect.mafd:value=0.01:function=greater" > >> -f null - > >>frame= 1 fps=0.0 q=-0.0 Lsize=N/A time=00:00:00.03 bitrate=N/A > >>speed=2.14x > >> > >>Signed-off-by: Limin Wang <lance.lmw...@gmail.com> > >>--- > >> doc/filters.texi | 9 +++++++++ > >> libavfilter/vf_freezedetect.c | 7 +++++++ > >> 2 files changed, 16 insertions(+) > >> > >>diff --git a/doc/filters.texi b/doc/filters.texi > >>index 55a8ebae56..cfc10c8479 100644 > >>--- a/doc/filters.texi > >>+++ b/doc/filters.texi > >>@@ -10800,6 +10800,15 @@ timestamp of the first frame of the freeze. The > >> @code{lavfi.freezedetect.freeze_end} metadata keys are set on the first > >> frame > >> after the freeze. > >> > >>+The @code{lavfi.freezedetect.mafd} metadata key is set for all frames > >>except the > >>+first reference frame. You can use it to drop frozen frames by metadata > >>select > >>+mode. Note that in this way the first few frozen frames(the detection > >>interval) > >>+are dropped also. An example is as follows: > >>+@example > >>+freezedetect,metadata=mode=select:key=lavfi.freezedetect.mafd:value=0.001:function=greater > >>+@end example > > No, this is not what this is. This way you drop in the detection > interval even if no freeze is detected. So this approach is only > slightly different to selecting a very small (less than a frame) > detection interval.
If one frame is detected as frozen frame, it'll be dropped. The freezedetect.mafd will be the mafd between the next frame with the first frozen frame, if it's frozen frame(<threeshold), still, it'll be continued drop. So we may think it's not frozen frame if only one frame mafd less than the threshold, so you need set the threshold very small to avoid misdetecting. With detection interval, you can't avoid misdetect still if the threshold isn't good choose. > > So I don't see the point of this patch. > > Regards, > Marton > _______________________________________________ > 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". _______________________________________________ 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".
