jpegdec: try to fix different flipping behavior of inteljpegs.

This may need some trial and error to find exactly how to identify them
so please report any intel jpegs that get fliped wrong.

Fixes Ticket511

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/mjpegdec.c

@@ -1468,7 +1468,7 @@ static int mjpeg_decode_com(MJpegDecodeContext *s)
                 // printf("mjpeg: workarounding buggy AVID\n");
             } else if (!strcmp(cbuf, "CS=ITU601"))
                 s->cs_itu601 = 1;
-            else if ((len > 20 && !strncmp(cbuf, "Intel(R) JPEG Library", 21)) ||
+            else if ((len > 31 && !strncmp(cbuf, "Intel(R) JPEG Library, version 1", 32)) ||
                      (len > 19 && !strncmp(cbuf, "Metasoft MJPEG Codec", 20)))
                 s->flipped = 1;