partial WRAW fourcc support, might need image flipping

Originally committed as revision 16000 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/raw.c

@@ -51,6 +51,7 @@ const PixelFormatTag ff_raw_pixelFormatTags[] = {
     /* quicktime */
     { PIX_FMT_UYVY422, MKTAG('2', 'v', 'u', 'y') },
     { PIX_FMT_UYVY422, MKTAG('A', 'V', 'U', 'I') }, /* FIXME merge both fields */
+    { PIX_FMT_PAL8,    MKTAG('W', 'R', 'A', 'W') },
 
     { PIX_FMT_NONE, 0 },
 };