CODEWITHSUNDEEP
videoffmpeg
dkrikun
dkrikun

Reputation: 1328

ffmpeg sdl output framerate too high

I'm using the following command-line to play a video via SDL:

ffmpeg -i input.mkv -f sdl "Video"

The video is being played too fast, ffmpeg prints that the framerate is ~500 (not constant, just playing as fast as possible) I've tried to limit the framerate as follows, but none of this has any effect:

ffmpeg -i input.mkv -r 25 -f sdl "Video"  
ffmpeg -i input.mkv -f sdl -r 25 "Video"  
ffmpeg -i input.mkv -framerate 25 -f sdl "Video"  
ffmpeg -i input.mkv -f sdl -framerate 25 "Video"

I'm using ffmpeg version ffmpeg-20150605-git-7be0f48-win64-static on Windows 7.
ffplay input.mkv works pretty well.

Thank you!

EDIT: console output for ffmpeg -i input.mkv -r 25 -f sdl "Video" follows:

ffmpeg version N-72662-g7be0f48 Copyright (c) 2000-2015 the FFmpeg developers
  built with gcc 4.9.2 (GCC)
  configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-av
isynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enab
le-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --
enable-libdcadec --enable-libfreetype --enable-libgme --enable-libgsm --enable-l
ibilbc --enable-libmodplug --enable-libmfx --enable-libmp3lame --enable-libopenc
ore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --ena
ble-librtmp --enable-libschroedinger --enable-libsoxr --enable-libspeex --enable
-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-aacenc --enabl
e-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable
-libwebp --enable-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --e
nable-lzma --enable-decklink --enable-zlib
  libavutil      54. 26.101 / 54. 26.101
  libavcodec     56. 41.101 / 56. 41.101
  libavformat    56. 34.100 / 56. 34.100
  libavdevice    56.  4.100 / 56.  4.100
  libavfilter     5. 16.101 /  5. 16.101
  libswscale      3.  1.101 /  3.  1.101
  libswresample   1.  2.100 /  1.  2.100
  libpostproc    53.  3.100 / 53.  3.100
Input #0, matroska,webm, from 'input.mkv':
  Metadata:
    ENCODER         : Lavf56.34.100
  Duration: 00:20:00.20, start: 0.000000, bitrate: 1006 kb/s
    Stream #0:0: Video: h264 (High), yuv420p, 720x304, SAR 1:1 DAR 45:19, 23.98
fps, 23.98 tbr, 1k tbn, 47.95 tbc (default)
    Metadata:
      BPS             : 813254
      BPS-eng         : 813254
      DURATION        : 02:13:35.090000000
      DURATION-eng    : 02:13:35.090000000
      NUMBER_OF_FRAMES: 192170
      NUMBER_OF_FRAMES-eng: 192170
      NUMBER_OF_BYTES : 814788601
      NUMBER_OF_BYTES-eng: 814788601
      _STATISTICS_WRITING_APP: mkvmerge v7.0.0 ('Where We Going') 32bit built on
 Jun  9 2014 15:08:34
      _STATISTICS_WRITING_APP-eng: mkvmerge v7.0.0 ('Where We Going') 32bit buil
t on Jun  9 2014 15:08:34
      _STATISTICS_WRITING_DATE_UTC: 2015-01-07 06:01:37
      _STATISTICS_WRITING_DATE_UTC-eng: 2015-01-07 06:01:37
      _STATISTICS_TAGS: BPS DURATION NUMBER_OF_FRAMES NUMBER_OF_BYTES
      _STATISTICS_TAGS-eng: BPS DURATION NUMBER_OF_FRAMES NUMBER_OF_BYTES
    Stream #0:1(eng): Audio: aac (LC), 48000 Hz, 5.1, fltp (default)
    Metadata:
      LANGUAGE        : eng
      BPS             : 185184
      BPS-eng         : 185184
      DURATION        : 02:13:35.125000000
      DURATION-eng    : 02:13:35.125000000
      NUMBER_OF_FRAMES: 375709
      NUMBER_OF_FRAMES-eng: 375709
      NUMBER_OF_BYTES : 185534548
      NUMBER_OF_BYTES-eng: 185534548
      _STATISTICS_WRITING_APP: mkvmerge v7.0.0 ('Where We Going') 32bit built on
 Jun  9 2014 15:08:34
      _STATISTICS_WRITING_APP-eng: mkvmerge v7.0.0 ('Where We Going') 32bit buil
t on Jun  9 2014 15:08:34
      _STATISTICS_WRITING_DATE_UTC: 2015-01-07 06:01:37
      _STATISTICS_WRITING_DATE_UTC-eng: 2015-01-07 06:01:37
      _STATISTICS_TAGS: BPS DURATION NUMBER_OF_FRAMES NUMBER_OF_BYTES
      _STATISTICS_TAGS-eng: BPS DURATION NUMBER_OF_FRAMES NUMBER_OF_BYTES
Output #0, sdl, to 'Video':
  Metadata:
    encoder         : Lavf56.34.100
    Stream #0:0: Video: rawvideo (I420 / 0x30323449), yuv420p, 720x304 [SAR 1:1
DAR 45:19], q=2-31, 200 kb/s, 25 fps, 25 tbn, 25 tbc (default)
    Metadata:
      BPS             : 813254
      BPS-eng         : 813254
      DURATION        : 02:13:35.090000000
      DURATION-eng    : 02:13:35.090000000
      NUMBER_OF_FRAMES: 192170
      NUMBER_OF_FRAMES-eng: 192170
      NUMBER_OF_BYTES : 814788601
      NUMBER_OF_BYTES-eng: 814788601
      _STATISTICS_WRITING_APP: mkvmerge v7.0.0 ('Where We Going') 32bit built on
 Jun  9 2014 15:08:34
      _STATISTICS_WRITING_APP-eng: mkvmerge v7.0.0 ('Where We Going') 32bit buil
t on Jun  9 2014 15:08:34
      _STATISTICS_WRITING_DATE_UTC: 2015-01-07 06:01:37
      _STATISTICS_WRITING_DATE_UTC-eng: 2015-01-07 06:01:37
      _STATISTICS_TAGS: BPS DURATION NUMBER_OF_FRAMES NUMBER_OF_BYTES
      _STATISTICS_TAGS-eng: BPS DURATION NUMBER_OF_FRAMES NUMBER_OF_BYTES
      encoder         : Lavc56.41.101 rawvideo
Stream mapping:
  Stream #0:0 -> #0:0 (h264 (native) -> rawvideo (native))
Press [q] to stop, [?] for help
frame=28726 fps=244 q=0.0 Lsize=N/A time=00:20:00.20 bitrate=N/A
video:9210274kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxi
ng overhead: unknown

Upvotes: 2

Views: 2647

Answers (1)

dkrikun
dkrikun

Reputation: 1328

After experimenting and reading docs, I have eventually figured the answer to my question:

ffmpeg -re -i input.mkv -f sdl "Video"

Explanation: both -r, -framerate options as well as fps filter all affect the produced video framerate and write it as metadata to the output file to be later consumed by a video player. For sdl (and some others) this has no effect because the video is just being outputted to and OpenGL surface, frame by frame. The speed at which this is performed depends solely on the ffmpeg processing speed (which in my case was somewhere ~500fps). In order to restrict this, -re option exists, which sets the processing speed to that defined by the input.

Upvotes: 4

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