[FFmpeg-trac] #2053(FFplay:new): ffplay's frame step not accurate

[FFmpeg]

#2053: ffplay's frame step not accurate
--------------------------------------+-----------------------------------
               Reporter:  ubitux      |                  Owner:
                   Type:  defect      |                 Status:  new
               Priority:  normal      |              Component:  FFplay
                Version:  git-master  |               Keywords:  framestep
             Blocked By:              |               Blocking:
Reproduced by developer:  0           |  Analyzed by developer:  0
--------------------------------------+-----------------------------------
 Frame stepping in ffplay doesn't work that well. It seems there is some
 kind of race. Start playing a relatively big video (with the drawtext
 filter as shown below to print the frame id), and switch to step-by-step
 mode ('s').

 {{{
 ☭ ./ffplay ~/samples/big_buck_bunny_1080p_h264.mov -vf
 drawtext=text=%{n}:expansion=normal:fontcolor=yellow:fontsize=50:fontfile=LiberationMono
 ffplay version N-48100-g3f72dbe Copyright (c) 2003-2012 the FFmpeg
 developers
   built on Dec 22 2012 12:54:34 with gcc 4.7.2 (GCC)
   configuration: --enable-gpl --enable-fontconfig --enable-libfreetype
 --enable-libmp3lame --enable-libvorbis --enable-libxvid --enable-libx264
 --enable-libvpx --enable-libtheora --enable-x11grab --enable-libopenjpeg
 --enable-libass --enable-libmodplug --enable-libv4l2 --cc=colorgcc
 --samples=/home/ubitux/fate-samples --prefix=/tmp/ffinstall --enable-
 runtime-cpudetect --enable-libcelt
   libavutil      52. 12.100 / 52. 12.100
   libavcodec     54. 81.100 / 54. 81.100
   libavformat    54. 49.102 / 54. 49.102
   libavdevice    54.  3.102 / 54.  3.102
   libavfilter     3. 29.100 /  3. 29.100
   libswscale      2.  1.103 /  2.  1.103
   libswresample   0. 17.102 /  0. 17.102
   libpostproc    52.  2.100 / 52.  2.100
 Input #0, mov,mp4,m4a,3gp,3g2,mj2, from
 '/home/ubitux/samples/big_buck_bunny_1080p_h264.mov':
   Metadata:
     major_brand     : qt
     minor_version   : 537199360
     compatible_brands: qt
     creation_time   : 2008-05-27 18:40:35
     timecode        : 00:00:00:00
   Duration: 00:09:56.46, start: 0.000000, bitrate: 9725 kb/s
     Stream #0:0(eng): Video: h264 (Main) (avc1 / 0x31637661), yuv420p,
 1920x1080, 9282 kb/s, 24 fps, 24 tbr, 2400 tbn, 4800 tbc
     Metadata:
       creation_time   : 2008-05-27 18:40:35
       handler_name    : Apple Alias Data Handler
     Stream #0:1(eng): Data: none (tmcd / 0x64636D74)
     Metadata:
       creation_time   : 2008-05-27 18:40:35
       handler_name    : Apple Alias Data Handler
       timecode        : 00:00:00:00
     Stream #0:2(eng): Audio: aac (mp4a / 0x6134706D), 48000 Hz, 5.1, fltp,
 437 kb/s
     Metadata:
       creation_time   : 2008-05-27 18:40:35
       handler_name    : Apple Alias Data Handler
 Frame changed from size:0x0 to size:1920x108001KB sq=    0B f=0/0
 }}}

 Now look at the counter; sometimes (1 out of 10-20 frames, not
 reproducible with the same frame id between different runs) the frame
 doesn't increment (and need one or two more key hits), or increment too
 quickly (often skip 1 frame).

-- 
Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/2053>
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