--- trunk/xvidcore/src/bitstream/mbcoding.c	2004/07/10 17:42:18	1485
+++ trunk/xvidcore/src/bitstream/mbcoding.c	2004/07/10 17:49:31	1486
@@ -19,7 +19,7 @@
  *  along with this program ; if not, write to the Free Software
  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  *
- * $Id: mbcoding.c,v 1.46 2004-03-22 22:36:23 edgomez Exp $
+ * $Id: mbcoding.c,v 1.47 2004-07-10 17:49:31 edgomez Exp $
  *
  ****************************************************************************/
 
@@ -958,6 +958,8 @@
 
 }
 
+#define GET_BITS(cache, n) ((cache)>>(32-(n)))
+
 static __inline int
 get_coeff(Bitstream * bs,
 		  int *run,
@@ -970,11 +972,13 @@
 	int32_t level;
 	REVERSE_EVENT *reverse_event;
 
+	uint32_t cache = BitstreamShowBits(bs, 32);
+	
 	if (short_video_header)		/* inter-VLCs will be used for both intra and inter blocks */
 		intra = 0;
 
-	if (BitstreamShowBits(bs, 7) != ESCAPE) {
-		reverse_event = &DCT3D[intra][BitstreamShowBits(bs, 12)];
+	if (GET_BITS(cache, 7) != ESCAPE) {
+		reverse_event = &DCT3D[intra][GET_BITS(cache, 12)];
 
 		if ((level = reverse_event->event.level) == 0)
 			goto error;
@@ -982,31 +986,35 @@
 		*last = reverse_event->event.last;
 		*run  = reverse_event->event.run;
 
-		BitstreamSkip(bs, reverse_event->len);
+		/* Don't forget to update the bitstream position */
+		BitstreamSkip(bs, reverse_event->len+1);
 
-		return BitstreamGetBits(bs, 1) ? -level : level;
+		return (GET_BITS(cache, reverse_event->len+1)&0x01) ? -level : level;
 	}
 
-	BitstreamSkip(bs, 7);
+	/* flush 7bits of cache */
+	cache <<= 7;
 
 	if (short_video_header) {
 		/* escape mode 4 - H.263 type, only used if short_video_header = 1  */
-		*last = BitstreamGetBit(bs);
-		*run = BitstreamGetBits(bs, 6);
-		level = BitstreamGetBits(bs, 8);
+		*last =  GET_BITS(cache, 1);
+		*run  = (GET_BITS(cache, 7) &0x3f);
+		level = (GET_BITS(cache, 15)&0xff);
 
 		if (level == 0 || level == 128)
 			DPRINTF(XVID_DEBUG_ERROR, "Illegal LEVEL for ESCAPE mode 4: %d\n", level);
 
+		/* We've "eaten" 22 bits */
+		BitstreamSkip(bs, 22);
+
 		return (level << 24) >> 24;
 	}
 
-	mode = BitstreamShowBits(bs, 2);
+	if ((mode = GET_BITS(cache, 2)) < 3) {
+		const int skip[3] = {1, 1, 2};
+		cache <<= skip[mode];
 
-	if (mode < 3) {
-		BitstreamSkip(bs, (mode == 2) ? 2 : 1);
-
-		reverse_event = &DCT3D[intra][BitstreamShowBits(bs, 12)];
+		reverse_event = &DCT3D[intra][GET_BITS(cache, 12)];
 
 		if ((level = reverse_event->event.level) == 0)
 			goto error;
@@ -1014,23 +1022,28 @@
 		*last = reverse_event->event.last;
 		*run  = reverse_event->event.run;
 
-		BitstreamSkip(bs, reverse_event->len);
-
-		if (mode < 2)			/* first escape mode, level is offset */
+		if (mode < 2) {
+			/* first escape mode, level is offset */
 			level += max_level[intra][*last][*run];
-		else					/* second escape mode, run is offset */
+		} else {
+			/* second escape mode, run is offset */
 			*run += max_run[intra][*last][level] + 1;
+		}
+		
+		/* Update bitstream position */
+		BitstreamSkip(bs, 7 + skip[mode] + reverse_event->len + 1);
 
-		return BitstreamGetBits(bs, 1) ? -level : level;
+		return (GET_BITS(cache, reverse_event->len+1)&0x01) ? -level : level;
 	}
 
 	/* third escape mode - fixed length codes */
-	BitstreamSkip(bs, 2);
-	*last = BitstreamGetBits(bs, 1);
-	*run = BitstreamGetBits(bs, 6);
-	BitstreamSkip(bs, 1);		/* marker */
-	level = BitstreamGetBits(bs, 12);
-	BitstreamSkip(bs, 1);		/* marker */
+	cache <<= 2;
+	*last =  GET_BITS(cache, 1);
+	*run  = (GET_BITS(cache, 7)&0x3f);
+	level = (GET_BITS(cache, 20)&0xfff);
+	
+	/* Update bitstream position */
+	BitstreamSkip(bs, 30);
 
 	return (level << 20) >> 20;
 
@@ -1072,12 +1085,17 @@
 }
 
 void
-get_inter_block(Bitstream * bs,
-				int16_t * block,
-				int direction)
+get_inter_block_h263(
+		Bitstream * bs,
+		int16_t * block,
+		int direction,
+		const int quant,
+		const uint16_t *matrix)
 {
 
 	const uint16_t *scan = scan_tables[direction];
+	const uint16_t quant_m_2 = quant << 1;
+	const uint16_t quant_add = (quant & 1 ? quant : quant - 1);
 	int p;
 	int level;
 	int run;
@@ -1092,17 +1110,58 @@
 		}
 		p += run;
 
-		block[scan[p]] = level;
+		if (level < 0) {
+			level = level*quant_m_2 - quant_add;
+			block[scan[p]] = (level >= -2048 ? level : -2048);
+		} else {
+			level = level * quant_m_2 + quant_add;
+			block[scan[p]] = (level <= 2047 ? level : 2047);
+		}		
+		p++;
+	} while (!last);
+}
+
+void
+get_inter_block_mpeg(
+		Bitstream * bs,
+		int16_t * block,
+		int direction,
+		const int quant,
+		const uint16_t *matrix)
+{
+	const uint16_t *scan = scan_tables[direction];
+	uint32_t sum = 0;
+	int p;
+	int level;
+	int run;
+	int last;
 
-		DPRINTF(XVID_DEBUG_COEFF,"block[%i] %i\n", scan[p], level);
-		/* DPRINTF(XVID_DEBUG_COEFF,"block[%i] %i %08x\n", scan[p], level, BitstreamShowBits(bs, 32)); */
+	p = 0;
+	do {
+		level = get_coeff(bs, &run, &last, 0, 0);
+		if (run == -1) {
+			DPRINTF(XVID_DEBUG_ERROR,"fatal: invalid run");
+			break;
+		}
+		p += run;
 
-		if (level < -2047 || level > 2047) {
-			DPRINTF(XVID_DEBUG_ERROR,"warning: inter overflow %i\n", level);
+		if (level < 0) {
+			level = ((2 * -level + 1) * matrix[scan[p]] * quant) >> 4;
+			block[scan[p]] = (level <= 2048 ? -level : -2048);
+		} else {
+			level = ((2 *  level + 1) * matrix[scan[p]] * quant) >> 4;
+			block[scan[p]] = (level <= 2047 ? level : 2047);
 		}
+
+		sum ^= block[scan[p]];
+		
 		p++;
 	} while (!last);
 
+	/*	mismatch control */
+	if ((sum & 1) == 0) {
+		block[63] ^= 1;
+	}
 }