[FFmpeg-trac] #63(undetermined:new): Purple bars appear when scaling a video with ffmpeg for windows

[FFmpeg]

#63: Purple bars appear when scaling a video with ffmpeg for windows
-------------------------------------+---------------------------
Reporter:  thebombzen                |       Owner:
    Type:  defect                    |      Status:  new
Priority:  normal                    |   Component:  undetermined
 Version:  git                       |  Resolution:
Keywords:  purple bars scale glitch  |  Blocked By:
Blocking:                            |  Reproduced:  0
Analyzed:  0                         |
-------------------------------------+---------------------------

Comment (by thebombzen):

 I found what is causing the problem. When compiled with --enable-runtime-
 cpudetect, the purple bars appear, but they disappear when it is compiled
 without it. This is the ffmpeg output from when it is compiled with
 --enable-runtime-cpudetect:

 [Leo at chessman ~]$ ./ffmpeg_g.exe -v 9 -loglevel 99 -i No-purple-bars.y4m
 -s 800x450 Yes-purple-bars.y4m
 ffmpeg version git-N-29343-g8a68697, Copyright (c) 2000-2011 the FFmpeg
 developers
   built on Apr 24 2011 18:28:28 with gcc 4.5.3 20110401 (prerelease)
   configuration: --enable-runtime-cpudetect --arch=i686 --target-
 os=mingw32 --enable-cross-compile --cross-
 prefix=/usr/i686-w64-mingw32/bin/ --enable-memalign-hack
   libavutil    51.  0. 0 / 51.  0. 0
   libavcodec   53.  1. 0 / 53.  1. 0
   libavformat  53.  0. 3 / 53.  0. 3
   libavdevice  53.  0. 0 / 53.  0. 0
   libavfilter   2.  0. 0 /  2.  0. 0
   libswscale    0. 13. 0 /  0. 13. 0
 [NULL @ 0012C400] Format yuv4mpegpipe probed with size=2048 and score=100
 [yuv4mpegpipe @ 0012C400] Probe buffer size limit 5000000 reached
 [yuv4mpegpipe @ 0012C400] Estimating duration from bitrate, this may be
 inaccurate
 Input #0, yuv4mpegpipe, from 'No-purple-bars.y4m':
   Duration: N/A, bitrate: N/A
     Stream #0.0, 2, 100/1199: Video: rawvideo, yuv420p, 1920x1080,
 100/1199, PAR 1:1 DAR 16:9, 11.99 tbr, 11.99 tbn, 11.99 tbc
 fixme:msvcrt:MSVCRT__wsopen_s : pmode 0x01b6 ignored
 [buffer @ 00173080] w:1920 h:1080 pixfmt:yuv420p
 [scale @ 001733A0] w:1920 h:1080 fmt:yuv420p -> w:800 h:450 fmt:yuv420p
 flags:0x4
 Output #0, yuv4mpegpipe, to 'Yes-purple-bars.y4m':
   Metadata:
     encoder         : Lavf53.0.3
     Stream #0.0, 0, 1/90000: Video: rawvideo, yuv420p, 800x450 [PAR 1:1
 DAR 16:9], 100/1199, q=2-31, 200 kb/s, 90k tbn, 11.99 tbc
 Stream mapping:
   Stream #0.0 -> #0.0
 Press [q] to stop encoding
 frame=   13 fps=  0 q=0.0 Lsize=    6856kB time=1.08
 bitrate=51798.0kbits/s
 video:0kB audio:0kB global headers:0kB muxing overhead inf%

 When I compiled without it, the purple bars weren't there and this is the
 output:

 [Leo at chessman ~]$ ./ffmpeg_g.exe -v 9 -loglevel 99 -i No-purple-bars.y4m
 -s 800x450 Yes-purple-bars.y4m
 ffmpeg version git-N-29343-g8a68697, Copyright (c) 2000-2011 the FFmpeg
 developers
   built on Apr 24 2011 18:35:51 with gcc 4.5.3 20110401 (prerelease)
   configuration: --arch=i686 --target-os=mingw32 --enable-cross-compile
 --cross-prefix=/usr/i686-w64-mingw32/bin/ --enable-memalign-hack
   libavutil    51.  0. 0 / 51.  0. 0
   libavcodec   53.  1. 0 / 53.  1. 0
   libavformat  53.  0. 3 / 53.  0. 3
   libavdevice  53.  0. 0 / 53.  0. 0
   libavfilter   2.  0. 0 /  2.  0. 0
   libswscale    0. 13. 0 /  0. 13. 0
 [NULL @ 0012C400] Format yuv4mpegpipe probed with size=2048 and score=100
 [yuv4mpegpipe @ 0012C400] Probe buffer size limit 5000000 reached
 [yuv4mpegpipe @ 0012C400] Estimating duration from bitrate, this may be
 inaccurate
 Input #0, yuv4mpegpipe, from 'No-purple-bars.y4m':
   Duration: N/A, bitrate: N/A
     Stream #0.0, 2, 100/1199: Video: rawvideo, yuv420p, 1920x1080,
 100/1199, PAR 1:1 DAR 16:9, 11.99 tbr, 11.99 tbn, 11.99 tbc
 fixme:msvcrt:MSVCRT__wsopen_s : pmode 0x01b6 ignored
 [buffer @ 00173080] w:1920 h:1080 pixfmt:yuv420p
 [scale @ 001733A0] w:1920 h:1080 fmt:yuv420p -> w:800 h:450 fmt:yuv420p
 flags:0xa0000004
 Output #0, yuv4mpegpipe, to 'Yes-purple-bars.y4m':
   Metadata:
     encoder         : Lavf53.0.3
     Stream #0.0, 0, 1/90000: Video: rawvideo, yuv420p, 800x450 [PAR 1:1
 DAR 16:9], 100/1199, q=2-31, 200 kb/s, 90k tbn, 11.99 tbc
 Stream mapping:
   Stream #0.0 -> #0.0
 Press [q] to stop encoding
 frame=   13 fps=  0 q=0.0 Lsize=    6856kB time=1.08
 bitrate=51798.0kbits/s
 video:0kB audio:0kB global headers:0kB muxing overhead inf%

-- 
Ticket URL: <http://ffmpeg.org/trac/ffmpeg/ticket/63#comment:5>
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