[FFmpeg-trac] #2053(FFplay:new): ffplay's frame step not accurate
FFmpeg
trac at avcodec.org
Sat Dec 22 16:19:46 CET 2012
#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>
FFmpeg <http://ffmpeg.org>
FFmpeg issue tracker
More information about the FFmpeg-trac
mailing list