fix decoding of rawvideo cyuv

[ami_stuff]

cyuv can be Creative YUV or rawvideo, curerently rawvideo is not identified correctly and fails to decode

​http://samples.mplayerhq.hu/V-codecs/CYUV.AVI

C:\>ffmpeg -i CYUV.AVI -vcodec msmpeg4v2 out.avi
ffmpeg version N-43287-gcde4741 Copyright (c) 2000-2012 the FFmpeg developers
  built on Aug  7 2012 02:22:47 with gcc 4.5.0 (GCC) 20100414 (Fedora MinGW 4.5.
0-1.fc14)
  configuration: --prefix=/var/www/users/research/ffmpeg/snapshots/build --arch=
x86 --target-os=mingw32 --cross-prefix=i686-pc-mingw32- --cc='ccache i686-pc-min
gw32-gcc' --enable-w32threads --enable-memalign-hack --enable-runtime-cpudetect
--enable-cross-compile --enable-static --disable-shared --extra-libs='-lws2_32 -
lwinmm -lpthread' --extra-cflags='--static -I/var/www/users/research/ffmpeg/snap
shots/build/include' --extra-ldflags='-static -L/var/www/users/research/ffmpeg/s
napshots/build/lib' --enable-bzlib --enable-zlib --enable-gpl --enable-version3
--enable-nonfree --enable-libx264 --enable-libspeex --enable-libtheora --enable-
libvorbis --enable-libfaac --enable-libxvid --enable-libopencore-amrnb --enable-
libopencore-amrwb --enable-libmp3lame --enable-libvpx --disable-decoder=libvpx
  libavutil      51. 66.101 / 51. 66.101
  libavcodec     54. 49.100 / 54. 49.100
  libavformat    54. 22.101 / 54. 22.101
  libavdevice    54.  2.100 / 54.  2.100
  libavfilter     3.  5.102 /  3.  5.102
  libswscale      2.  1.101 /  2.  1.101
  libswresample   0. 15.100 /  0. 15.100
  libpostproc    52.  0.100 / 52.  0.100
Guessed Channel Layout for  Input Stream #0.1 : mono
Input #0, avi, from 'CYUV.AVI':
  Duration: 00:00:00.93, start: 0.000000, bitrate: 18582 kb/s
    Stream #0:0: Video: cyuv (cyuv / 0x76757963), yuv411p, 320x240, 15 tbr, 15 t
bn, 15 tbc
    Stream #0:1: Audio: pcm_u8 ([1][0][0][0] / 0x0001), 11025 Hz, mono, u8, 88 k
b/s
Output #0, avi, to 'out.avi':
  Metadata:
    ISFT            : Lavf54.22.101
    Stream #0:0: Video: msmpeg4v2 (MP42 / 0x3234504D), yuv420p, 320x240, q=2-31,
 200 kb/s, 15 tbn, 15 tbc
    Stream #0:1: Audio: mp3 (U[0][0][0] / 0x0055), 11025 Hz, mono, s16
Stream mapping:
  Stream #0:0 -> #0:0 (cyuv -> msmpeg4v2)
  Stream #0:1 -> #0:1 (pcm_u8 -> libmp3lame)
Press [q] to stop, [?] for help
[cyuv @ 0x1ead700] got a buffer with 153600 bytes when 57648 were expected
Error while decoding stream #0:0: Error number -1 occurred
[cyuv @ 0x1ead700] got a buffer with 153600 bytes when 57648 were expected
Error while decoding stream #0:0: Error number -1 occurred
[cyuv @ 0x1ead700] got a buffer with 153600 bytes when 57648 were expected
Error while decoding stream #0:0: Error number -1 occurred
[cyuv @ 0x1ead700] got a buffer with 153600 bytes when 57648 were expected
Error while decoding stream #0:0: Error number -1 occurred
[cyuv @ 0x1ead700] got a buffer with 153600 bytes when 57648 were expected
Error while decoding stream #0:0: Error number -1 occurred
[cyuv @ 0x1ead700] got a buffer with 153600 bytes when 57648 were expected
Error while decoding stream #0:0: Error number -1 occurred
[cyuv @ 0x1ead700] got a buffer with 153600 bytes when 57648 were expected
Error while decoding stream #0:0: Error number -1 occurred
[cyuv @ 0x1ead700] got a buffer with 153600 bytes when 57648 were expected
Error while decoding stream #0:0: Error number -1 occurred
[cyuv @ 0x1ead700] got a buffer with 153600 bytes when 57648 were expected
Error while decoding stream #0:0: Error number -1 occurred
[cyuv @ 0x1ead700] got a buffer with 153600 bytes when 57648 were expected
Error while decoding stream #0:0: Error number -1 occurred
[cyuv @ 0x1ead700] got a buffer with 153600 bytes when 57648 were expected
Error while decoding stream #0:0: Error number -1 occurred
[cyuv @ 0x1ead700] got a buffer with 153600 bytes when 57648 were expected
Error while decoding stream #0:0: Error number -1 occurred
[cyuv @ 0x1ead700] got a buffer with 153600 bytes when 57648 were expected
Error while decoding stream #0:0: Error number -1 occurred
[cyuv @ 0x1ead700] got a buffer with 153600 bytes when 57648 were expected
Error while decoding stream #0:0: Error number -1 occurred
frame=    0 fps=0.0 q=0.0 Lsize=      12kB time=00:00:00.00 bitrate=   0.0kbits/
s
video:0kB audio:2kB subtitle:0 global headers:0kB muxing overhead 498.086124%