[FFmpeg-devel] [PATCH] vf_fps: when reading EOF, using current_pts to duplicate the last frame if needed.
Thierry Foucu
tfoucu at gmail.com
Tue Sep 12 00:03:08 EEST 2017
See new patch.
Getting 12 frame out when down-sample (instead of 13)
===================================
I tried it against ticket 2674 and here is the output:
ffmpeg -loglevel verbose -i 24fps.avi -vf fps=12 -y 12fps.avi
ffmpeg version N-87234-g9a32769f5e Copyright (c) 2000-2017 the FFmpeg
developers
built with gcc 4.8 (Ubuntu 4.8.4-2ubuntu1~14.04.3)
configuration:
libavutil 55. 74.100 / 55. 74.100
libavcodec 57.105.100 / 57.105.100
libavformat 57. 81.100 / 57. 81.100
libavdevice 57. 8.100 / 57. 8.100
libavfilter 6.103.100 / 6.103.100
libswscale 4. 7.103 / 4. 7.103
libswresample 2. 8.100 / 2. 8.100
Input #0, avi, from '24fps.avi':
Metadata:
encoder : Lavf57.81.100
Duration: 00:00:01.00, start: 0.000000, bitrate: 368 kb/s
Stream #0:0: Video: mpeg4 (Simple Profile), 1 reference frame (FMP4 /
0x34504D46), yuv420p(left), 320x240 [SAR 1:1 DAR 4:3], 24 fps, 24 tbr, 24
tbn, 24 tbc
Stream mapping:
Stream #0:0 -> #0:0 (mpeg4 (native) -> mpeg4 (native))
Press [q] to stop, [?] for help
[Parsed_fps_0 @ 0x304e4a0] fps=12/1
[graph 0 input from stream 0:0 @ 0x31c0aa0] w:320 h:240 pixfmt:yuv420p
tb:1/24 fr:24/1 sar:1/1 sws_param:flags=2
Output #0, avi, to '12fps.avi':
Metadata:
ISFT : Lavf57.81.100
Stream #0:0: Video: mpeg4, 1 reference frame (FMP4 / 0x34504D46),
yuv420p(left), 320x240 [SAR 1:1 DAR 4:3], q=2-31, 200 kb/s, 12 fps, 12 tbn,
12 tbc
Metadata:
encoder : Lavc57.105.100 mpeg4
Side data:
cpb: bitrate max/min/avg: 0/0/200000 buffer size: 0 vbv_delay: -1
No more output streams to write to, finishing.
frame= 12 fps=0.0 q=2.0 Lsize= 26kB time=00:00:01.00 bitrate=
211.3kbits/s speed=39.8x
video:20kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB
muxing overhead: 29.731853%
Input file #0 (24fps.avi):
Input stream #0:0 (video): 24 packets read (39693 bytes); 24 frames
decoded;
Total: 24 packets (39693 bytes) demuxed
Output file #0 (12fps.avi):
Output stream #0:0 (video): 12 frames encoded; 12 packets muxed (20362
bytes);
Total: 12 packets (20362 bytes) muxed
[Parsed_fps_0 @ 0x304e4a0] 24 frames in, 12 frames out; 12 frames dropped,
0 frames duplicated.
getting 48 frames out instead of 47
=====================================================
ffmpeg -loglevel verbose -i 24fps.avi -vf fps=48 -y 48fps.avi
ffmpeg version N-87234-g9a32769f5e Copyright (c) 2000-2017 the FFmpeg
developers
built with gcc 4.8 (Ubuntu 4.8.4-2ubuntu1~14.04.3)
configuration:
libavutil 55. 74.100 / 55. 74.100
libavcodec 57.105.100 / 57.105.100
libavformat 57. 81.100 / 57. 81.100
libavdevice 57. 8.100 / 57. 8.100
libavfilter 6.103.100 / 6.103.100
libswscale 4. 7.103 / 4. 7.103
libswresample 2. 8.100 / 2. 8.100
Input #0, avi, from '24fps.avi':
Metadata:
encoder : Lavf57.81.100
Duration: 00:00:01.00, start: 0.000000, bitrate: 368 kb/s
Stream #0:0: Video: mpeg4 (Simple Profile), 1 reference frame (FMP4 /
0x34504D46), yuv420p(left), 320x240 [SAR 1:1 DAR 4:3], 24 fps, 24 tbr, 24
tbn, 24 tbc
Stream mapping:
Stream #0:0 -> #0:0 (mpeg4 (native) -> mpeg4 (native))
Press [q] to stop, [?] for help
[Parsed_fps_0 @ 0x34ea4a0] fps=48/1
[graph 0 input from stream 0:0 @ 0x365ca20] w:320 h:240 pixfmt:yuv420p
tb:1/24 fr:24/1 sar:1/1 sws_param:flags=2
Output #0, avi, to '48fps.avi':
Metadata:
ISFT : Lavf57.81.100
Stream #0:0: Video: mpeg4, 1 reference frame (FMP4 / 0x34504D46),
yuv420p(left), 320x240 [SAR 1:1 DAR 4:3], q=2-31, 200 kb/s, 48 fps, 48 tbn,
48 tbc
Metadata:
encoder : Lavc57.105.100 mpeg4
Side data:
cpb: bitrate max/min/avg: 0/0/200000 buffer size: 0 vbv_delay: -1
No more output streams to write to, finishing.
frame= 48 fps=0.0 q=2.0 Lsize= 67kB time=00:00:01.00 bitrate=
552.9kbits/s speed=28.2x
video:61kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB
muxing overhead: 11.158647%
Input file #0 (24fps.avi):
Input stream #0:0 (video): 24 packets read (39693 bytes); 24 frames
decoded;
Total: 24 packets (39693 bytes) demuxed
Output file #0 (48fps.avi):
Output stream #0:0 (video): 48 frames encoded; 48 packets muxed (62176
bytes);
Total: 48 packets (62176 bytes) muxed
[Parsed_fps_0 @ 0x34ea4a0] 24 frames in, 48 frames out; 0 frames dropped,
23 frames duplicated.
On Fri, Sep 8, 2017 at 4:33 PM, Thomas Mundt <tmundt75 at gmail.com> wrote:
> Hi Thierry,
>
> 2017-09-08 19:03 GMT+02:00 Thierry Foucu <tfoucu at gmail.com>:
>
> > ---
> > libavfilter/vf_fps.c | 42 ++++++++++++++++++++++++++++++
> > +++++++-----
> > tests/ref/fate/filter-fps | 6 ++++++
> > tests/ref/fate/filter-fps-r | 4 ++++
> > 3 files changed, 47 insertions(+), 5 deletions(-)
> >
> > diff --git a/libavfilter/vf_fps.c b/libavfilter/vf_fps.c
> > index 20ccd797d1..e450723173 100644
> > --- a/libavfilter/vf_fps.c
> > +++ b/libavfilter/vf_fps.c
> > @@ -34,6 +34,8 @@
> > #include "libavutil/opt.h"
> > #include "libavutil/parseutils.h"
> >
> > +#define FF_INTERNAL_FIELDS 1
> > +#include "framequeue.h"
> > #include "avfilter.h"
> > #include "internal.h"
> > #include "video.h"
> > @@ -137,13 +139,43 @@ static int request_frame(AVFilterLink *outlink)
> > AVFrame *buf;
> >
> > av_fifo_generic_read(s->fifo, &buf, sizeof(buf), NULL);
> > - buf->pts = av_rescale_q(s->first_pts,
> > ctx->inputs[0]->time_base,
> > - outlink->time_base) + s->frames_out;
> > + if (av_fifo_size(s->fifo)) {
> > + buf->pts = av_rescale_q(s->first_pts,
> > ctx->inputs[0]->time_base,
> > + outlink->time_base) +
> > s->frames_out;
> >
> > - if ((ret = ff_filter_frame(outlink, buf)) < 0)
> > - return ret;
> > + if ((ret = ff_filter_frame(outlink, buf)) < 0)
> > + return ret;
> >
> > - s->frames_out++;
> > + s->frames_out++;
> > + } else {
> > + /* This is the last frame, we may have to duplicate it
> to
> > match
> > + * the last frame duration */
> > + int j;
> > + int delta = av_rescale_q_rnd(ctx->inputs[
> 0]->current_pts
> > - s->first_pts,
> > + ctx->inputs[0]->time_base,
> > + outlink->time_base,
> > s->rounding) - s->frames_out ;
> > + if (delta > 0 ) {
> > + for (j = 0; j < delta; j++) {
> > + AVFrame *dup = av_frame_clone(buf);
> > +
> > + av_log(ctx, AV_LOG_DEBUG, "Duplicating
> frame.\n");
> > + dup->pts = av_rescale_q(s->first_pts,
> > ctx->inputs[0]->time_base,
> > + outlink->time_base) +
> > s->frames_out;
> > +
> > + if ((ret = ff_filter_frame(outlink, dup)) < 0)
> > + return ret;
> > +
> > + s->frames_out++;
> > + }
> > + } else {
> > + buf->pts = av_rescale_q(s->first_pts,
> > ctx->inputs[0]->time_base,
> > + outlink->time_base) +
> > s->frames_out;
> > +
> > + if ((ret = ff_filter_frame(outlink, buf)) < 0)
> > + return ret;
> > + s->frames_out++;
> > + }
> > + }
> > }
> > return 0;
> > }
> >
>
> Your patch only resolves wrong framerate conversion durations for output
> fps > input fps. I think the EOF misbehaviour should be solved for any
> conversion.
> I wrote a similar patch some months ago:
> http://ffmpeg.org/pipermail/ffmpeg-devel/2017-March/209085.html
> It was rejected because of the use of pkt_duration, like your first patch,
> and the dupliction of non-trivial code. Also it used average frame duration
> when pkt_duration was not available.
> Now, after the patches Nicolas wrote and pushed the last weeks, it should
> be possible to find a general solution.
> Check the example at ticket #2674 for testing several framerate
> conversions.
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel at ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
>
More information about the ffmpeg-devel
mailing list