theora alpha3 support (with maintaining backward compatibility, maybe we...

theora alpha3 support (with maintaining backward compatibility, maybe we should remove all backward compatibility codes after final theora release?)

Originally committed as revision 2527 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/vp3.c

@@ -2765,7 +2765,9 @@ static int vp3_decode_frame(AVCodecContext *avctx,
     {
 	s->last_quality_index = s->quality_index;
 	s->quality_index = get_bits(&gb, 6);
-	if ( s->keyframe)
+	if (s->theora >= 0x030300)
+	    skip_bits1(&gb);
+	if (s->keyframe)
 	{
 	    if (get_bits1(&gb))
 		av_log(s->avctx, AV_LOG_ERROR, "Theora: warning, unsupported keyframe coding type?!\n");
@@ -2924,9 +2926,12 @@ static int theora_decode_header(AVCodecContext *avctx, GetBitContext gb)
     av_log(avctx, AV_LOG_INFO, "Theora bitstream version %d.%d.%d\n",
 	major, minor, micro);
 
+    /* FIXME: endianess? */
+    s->theora = (major << 16) | (minor << 8) | micro;
+
     /* 3.3.0 aka alpha3 has the same frame orientation as original vp3 */
     /* but previous versions have the image flipped relative to vp3 */
-    if ((major <= 3) && (minor < 3))
+    if (s->theora < 0x030300)
     {
 	s->flipped_image = 1;
         av_log(avctx, AV_LOG_DEBUG, "Old (<alpha3) Theora bitstream, flipped image\n");
@@ -2946,12 +2951,19 @@ static int theora_decode_header(AVCodecContext *avctx, GetBitContext gb)
     skip_bits(&gb, 24); /* aspect numerator */
     skip_bits(&gb, 24); /* aspect denumerator */
     
-    skip_bits(&gb, 5); /* keyframe frequency force */
+    if (s->theora < 0x030300)
+	skip_bits(&gb, 5); /* keyframe frequency force */
     skip_bits(&gb, 8); /* colorspace */
     skip_bits(&gb, 24); /* bitrate */
 
     skip_bits(&gb, 6); /* last(?) quality index */
     
+    if (s->theora >= 0x030300)
+    {
+	skip_bits(&gb, 5); /* keyframe frequency force */
+	skip_bits(&gb, 5); /* spare bits */
+    }
+    
 //    align_get_bits(&gb);
     
     avctx->width = s->width;