framecrcenc: workaround design flaw in sidedata palette

This should be reverted once palettes are dealt with in a endian independant way
in packets
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavformat/framecrcenc.c

@@ -34,13 +34,22 @@ static int framecrc_write_packet(struct AVFormatContext *s, AVPacket *pkt)
     if (pkt->flags != AV_PKT_FLAG_KEY)
         av_strlcatf(buf, sizeof(buf), ", F=0x%0X", pkt->flags);
     if (pkt->side_data_elems) {
-        int i;
+        int i, j;
         av_strlcatf(buf, sizeof(buf), ", S=%d", pkt->side_data_elems);
 
         for (i=0; i<pkt->side_data_elems; i++) {
-            uint32_t side_data_crc = av_adler32_update(0,
-                                                    pkt->side_data[i].data,
-                                                    pkt->side_data[i].size);
+            uint32_t side_data_crc = 0;
+            if (HAVE_BIGENDIAN && AV_PKT_DATA_PALETTE == pkt->side_data[i].type) {
+                for (j=0; j<pkt->side_data[i].size; j++) {
+                    side_data_crc = av_adler32_update(side_data_crc,
+                                                      pkt->side_data[i].data + (j^3),
+                                                      1);
+                }
+            } else {
+                side_data_crc = av_adler32_update(0,
+                                                  pkt->side_data[i].data,
+                                                  pkt->side_data[i].size);
+            }
             av_strlcatf(buf, sizeof(buf), ", %8d, 0x%08x", pkt->side_data[i].size, side_data_crc);
         }
     }