[FFmpeg-trac] #7121(undetermined:new): Changing framerate of an MJPEG stream with piping drops malformed images

[FFmpeg]

#7121: Changing framerate of an MJPEG stream with piping drops malformed images
-------------------------------------+-------------------------------------
             Reporter:  firesharker  |                    Owner:
                 Type:  defect       |                   Status:  new
             Priority:  normal       |                Component:
              Version:  unspecified  |  undetermined
             Keywords:               |               Resolution:
             Blocking:               |               Blocked By:
Analyzed by developer:  0            |  Reproduced by developer:  0
-------------------------------------+-------------------------------------

Comment (by firesharker):

 Tested with the 20180402 nightly build and 3.2.4

 {{{
 $ ffmpeg -i test.avi -c copy -f image2pipe - | ffmpeg -f image2pipe
 -framerate 10 -i - -c copy out.avi
 ffmpeg version N-45595-g5710fdaea-static https://johnvansickle.com/ffmpeg/
 ffmpeg version N-45595-g5710fdaea-static https://johnvansickle.com/ffmpeg/
 Copyright (c) 2000-2018 the FFmpeg developers
  Copyright (c) 2000-2018 the FFmpeg developers  built with gcc 6.3.0
 (Debian 6.3.0-18+deb9u1) 20170516

   configuration: --enable-gpl --enable-version3 --enable-static --disable-
 debug --disable-ffplay --disable-indev=sndio --disable-outdev=sndio
 --cc=gcc-6 --enable-fontconfig --enable-frei0r --enable-gnutls --enable-
 gray --enable-libfribidi --enable-libass --enable-libfreetype --enable-
 libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-
 libopenjpeg --enable-librubberband --enable-libsoxr --enable-libspeex
 --enable-libvorbis --enable-libopus --enable-libtheora --enable-libvidstab
 --enable-libvo-amrwbenc --enable-libvpx --enable-libwebp --enable-libx264
 --enable-libx265 --enable-libxvid --enable-libzimg
   built with gcc 6.3.0 (Debian 6.3.0-18+deb9u1) 20170516
   configuration: --enable-gpl --enable-version3 --enable-static --disable-
 debug --disable-ffplay --disable-indev=sndio --disable-outdev=sndio
 --cc=gcc-6 --enable-fontconfig --enable-frei0r --enable-gnutls --enable-
 gray --enable-libfribidi --enable-libass --enable-libfreetype --enable-
 libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-
 libopenjpeg --enable-librubberband --enable-libsoxr --enable-libspeex
 --enable-libvorbis --enable-libopus --enable-libtheora --enable-libvidstab
 --enable-libvo-amrwbenc --enable-libvpx --enable-libwebp --enable-libx264
 --enable-libx265 --enable-libxvid --enable-libzimg
   libavutil      56. 12.100 / 56. 12.100
   libavcodec     58. 17.100 / 58. 17.100
   libavformat    58. 10.100 / 58. 10.100
   libavdevice    58.  2.100 / 58.  2.100
   libavutil      56. 12.100 / 56. 12.100
   libavfilter     7. 14.100 /  7. 14.100
   libavcodec     58. 17.100 / 58. 17.100
   libswscale      5.  0.102 /  5.  0.102
   libavformat    58. 10.100 / 58. 10.100
   libswresample   3.  0.101 /  3.  0.101
   libavdevice    58.  2.100 / 58.  2.100
   libpostproc    55.  0.100 / 55.  0.100
   libavfilter     7. 14.100 /  7. 14.100
   libswscale      5.  0.102 /  5.  0.102
   libswresample   3.  0.101 /  3.  0.101
   libpostproc    55.  0.100 / 55.  0.100
 Input #0, avi, from 'test.avi':
   Metadata:
     encoder         : Lavf57.56.101
   Duration: 00:00:25.00, start: 0.000000, bitrate: 699 kb/s
     Stream #0:0: Video: mjpeg (MJPG / 0x47504A4D), yuvj420p(pc,
 bt470bg/unknown/unknown), 1280x720, 726 kb/s, 1 fps, 1 tbr, 1 tbn, 1 tbc
 Output #0, image2pipe, to 'pipe:':
   Metadata:
     encoder         : Lavf58.10.100
     Stream #0:0: Video: mjpeg (MJPG / 0x47504A4D), yuvj420p(pc,
 bt470bg/unknown/unknown), 1280x720, q=2-31, 726 kb/s, 1 fps, 1 tbr, 1 tbn,
 1 tbc
 Stream mapping:
   Stream #0:0 -> #0:0 (copy)
 Press [q] to stop, [?] for help
 frame=   25 fps=0.0 q=-1.0 Lsize=    2128kB time=00:00:25.00 bitrate=
 697.4kbits/s speed=9.12e+03x
 video:2128kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB
 muxing overhead: 0.000000%
 Input #0, image2pipe, from 'pipe:':
   Duration: N/A, bitrate: N/A
     Stream #0:0: Video: mjpeg, yuvj420p(pc, bt470bg/unknown/unknown),
 1280x720, 10 fps, 10 tbr, 10 tbn, 10 tbc
 Output #0, avi, to 'out.avi':
   Metadata:
     ISFT            : Lavf58.10.100
     Stream #0:0: Video: mjpeg (MJPG / 0x47504A4D), yuvj420p(pc,
 bt470bg/unknown/unknown), 1280x720, q=2-31, 10 fps, 10 tbr, 10 tbn, 10 tbc
 Stream mapping:
   Stream #0:0 -> #0:0 (copy)
 frame=    3 fps=0.0 q=-1.0 Lsize=    2134kB time=00:00:00.30
 bitrate=58270.5kbits/s speed= 341x
 video:2128kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB
 muxing overhead: 0.264203%

 }}}

 (My [https://video.stackexchange.com/questions/23674/how-to-change-
 framerate-with-ffmpeg-without-re-encoding original SE question])

--
Ticket URL: <https://trac.ffmpeg.org/ticket/7121#comment:4>
FFmpeg <https://ffmpeg.org>
FFmpeg issue tracker