Increase Sierra VMD palette dynamics.

libavcodec/vmdav.c

@@ -265,6 +265,7 @@ static void vmd_decode(VmdVideoContext *s)
             g = *p++ * 4;
             b = *p++ * 4;
             palette32[i] = 0xFF << 24 | r << 16 | g << 8 | b;
+            palette32[i] |= palette32[i] >> 6 & 0x30303;
         }
     }
     if (p < p_end) {