[FFmpeg-trac] #904(swscale:new): yuv2rgb_mmx.c not allowing yuv422p

[FFmpeg]

#904: yuv2rgb_mmx.c not allowing yuv422p
--------------------------------+-----------------------------------
             Reporter:  ffong   |                    Owner:  michael
                 Type:  defect  |                   Status:  new
             Priority:  normal  |                Component:  swscale
              Version:  0.8.9   |               Resolution:
             Keywords:          |               Blocked By:
             Blocking:          |  Reproduced by developer:  0
Analyzed by developer:  0       |
--------------------------------+-----------------------------------

Comment (by ffong):

 The whole thing is very simple. Converting yuv422p to bgr24 on Intel with
 MMX would give warnings "No accelerated conversion from yuv422p to bgr24".
 It's expected from the current code at ffmpeg-0.8.9 release. But what I
 don't understand is, if it is not supporting yuv422p. How come there is a
 recent change to yuv2rgb_template.c that checks for yuv422p? I modified
 the code to allow yuv422p and it seems to do OK. Maybe some loss in chroma
 sampling but in general does not crash or anything. So I wonder if the
 rejection of yuv422p at libswscale/x86/yuv2rgb_mmx.c is necessary.

 Here is the console output.
 $ ../install-0.8.9/bin/ffmpeg.exe -i ../Huff_Conv2YUV.avi -pix_fmt bgr24
 -f ima
 ge2 '%03d.bmp' -t 5
 ffmpeg version 0.8.9, Copyright (c) 2000-2011 the FFmpeg developers
   built on Jan 10 2012 20:56:05 with gcc 4.6.1
   configuration: --prefix=/home/Frankie/ffmpeg-0.8.9/../install-0.8.9/
 --enable-
 gpl --enable-version3 --arch=x86 --enable-runtime-cpudetect --enable-
 w32threads
 --enable-memalign-hack --disable-avfilter --disable-postproc
   libavutil    51.  9. 1 / 51.  9. 1
   libavcodec   53.  8. 0 / 53.  8. 0
   libavformat  53.  5. 0 / 53.  5. 0
   libavdevice  53.  1. 1 / 53.  1. 1
   libswscale    2.  0. 0 /  2.  0. 0
 Input #0, avi, from '../Huff_Conv2YUV.avi':
   Duration: 00:00:23.00, start: 0.000000, bitrate: 65081 kb/s
     Stream #0.0: Video: huffyuv, yuv422p, 704x576, 25 tbr, 25 tbn, 25 tbc
 Output #0, image2, to '%03d.bmp':
   Metadata:
     encoder         : Lavf53.5.0
     Stream #0.0: Video: bmp, bgr24, 704x576, q=2-31, 200 kb/s, 90k tbn, 25
 tbc
 Stream mapping:
   Stream #0.0 -> #0.0
 Press [q] to stop, [?] for help
 [swscaler @ 0161b000] No accelerated colorspace conversion found from
 yuv422p to
  bgr24.
 frame=   29 fps=  0 q=0.0 size=      -0kB time=00:00:01.16 bitrate=
 -0.2kbits/s
 frame=   35 fps= 29 q=0.0 size=      -0kB time=00:00:01.40 bitrate=
 -0.1kbits/s
 frame=   38 fps= 15 q=0.0 size=      -0kB time=00:00:01.52 bitrate=
 -0.1kbits/s
 frame=   40 fps= 12 q=0.0 size=      -0kB time=00:00:01.60 bitrate=
 -0.1kbits/s
 frame=   43 fps= 11 q=0.0 size=      -0kB time=00:00:01.72 bitrate=
 -0.1kbits/s
 frame=   53 fps= 12 q=0.0 size=      -0kB time=00:00:02.12 bitrate=
 -0.1kbits/s
 frame=   60 fps= 12 q=0.0 size=      -0kB time=00:00:02.40 bitrate=
 -0.1kbits/s
 frame=   65 fps= 12 q=0.0 size=      -0kB time=00:00:02.60 bitrate=
 -0.1kbits/s
 frame=   71 fps= 12 q=0.0 size=      -0kB time=00:00:02.84 bitrate=
 -0.1kbits/s
 frame=   75 fps= 11 q=0.0 size=      -0kB time=00:00:03.00 bitrate=
 -0.1kbits/s
 frame=   80 fps= 11 q=0.0 size=      -0kB time=00:00:03.20 bitrate=
 -0.1kbits/s
 frame=   86 fps= 11 q=0.0 size=      -0kB time=00:00:03.44 bitrate=
 -0.1kbits/s
 frame=   91 fps= 11 q=0.0 size=      -0kB time=00:00:03.64 bitrate=
 -0.0kbits/s
 frame=   95 fps= 11 q=0.0 size=      -0kB time=00:00:03.80 bitrate=
 -0.0kbits/s
 frame=  101 fps= 11 q=0.0 size=      -0kB time=00:00:04.04 bitrate=
 -0.0kbits/s
 frame=  105 fps= 10 q=0.0 size=      -0kB time=00:00:04.20 bitrate=
 -0.0kbits/s
 frame=  110 fps= 10 q=0.0 size=      -0kB time=00:00:04.40 bitrate=
 -0.0kbits/s
 frame=  116 fps= 10 q=0.0 size=      -0kB time=00:00:04.64 bitrate=
 -0.0kbits/s
 frame=  120 fps= 10 q=0.0 size=      -0kB time=00:00:04.80 bitrate=
 -0.0kbits/s
 frame=  125 fps= 10 q=0.0 Lsize=      -0kB time=00:00:05.00 bitrate=
 -0.0kbits/
 s
 video:148507kB audio:0kB global headers:0kB muxing overhead -100.000014%

-- 
Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/904#comment:6>
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