--- decoder.c	2005/03/27 03:59:41	1.69
+++ decoder.c	2005/08/01 18:37:46	1.72
@@ -20,7 +20,7 @@
  *  along with this program ; if not, write to the Free Software
  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  *
- * $Id: decoder.c,v 1.69 2005/03/27 03:59:41 suxen_drol Exp $
+ * $Id: decoder.c,v 1.72 2005/08/01 18:37:46 Isibaar Exp $
  *
  ****************************************************************************/
 
@@ -73,12 +73,20 @@
 
 	image_destroy(&dec->gmc, dec->edged_width, dec->edged_height);
 
-	if (dec->last_mbs)
-		xvid_free(dec->last_mbs);
-	if (dec->mbs)
-		xvid_free(dec->mbs);
-	if (dec->qscale)
-		xvid_free(dec->qscale);
+  image_null(&dec->cur);
+  image_null(&dec->refn[0]);
+  image_null(&dec->refn[1]);
+  image_null(&dec->tmp);
+  image_null(&dec->qtmp);
+  image_null(&dec->gmc);
+
+
+  xvid_free(dec->last_mbs);
+  xvid_free(dec->mbs);
+  xvid_free(dec->qscale);
+  dec->last_mbs = NULL;
+  dec->mbs = NULL;
+  dec->qscale = NULL;
 
 	/* realloc */
 	dec->mb_width = (dec->width + 15) / 16;
@@ -87,80 +95,27 @@
 	dec->edged_width = 16 * dec->mb_width + 2 * EDGE_SIZE;
 	dec->edged_height = 16 * dec->mb_height + 2 * EDGE_SIZE;
 
-	if (image_create(&dec->cur, dec->edged_width, dec->edged_height)) {
-		xvid_free(dec);
-		return XVID_ERR_MEMORY;
-	}
-
-	if (image_create(&dec->refn[0], dec->edged_width, dec->edged_height)) {
-		image_destroy(&dec->cur, dec->edged_width, dec->edged_height);
-		xvid_free(dec);
-		return XVID_ERR_MEMORY;
-	}
-
-	/* Support B-frame to reference last 2 frame */
-	if (image_create(&dec->refn[1], dec->edged_width, dec->edged_height)) {
-		image_destroy(&dec->cur, dec->edged_width, dec->edged_height);
-		image_destroy(&dec->refn[0], dec->edged_width, dec->edged_height);
-		xvid_free(dec);
-		return XVID_ERR_MEMORY;
-	}
-	if (image_create(&dec->tmp, dec->edged_width, dec->edged_height)) {
-		image_destroy(&dec->cur, dec->edged_width, dec->edged_height);
-		image_destroy(&dec->refn[0], dec->edged_width, dec->edged_height);
-		image_destroy(&dec->refn[1], dec->edged_width, dec->edged_height);
-		xvid_free(dec);
-		return XVID_ERR_MEMORY;
-	}
-
-	if (image_create(&dec->qtmp, dec->edged_width, dec->edged_height)) {
-		image_destroy(&dec->cur, dec->edged_width, dec->edged_height);
-		image_destroy(&dec->refn[0], dec->edged_width, dec->edged_height);
-		image_destroy(&dec->refn[1], dec->edged_width, dec->edged_height);
-		image_destroy(&dec->tmp, dec->edged_width, dec->edged_height);
-		xvid_free(dec);
-		return XVID_ERR_MEMORY;
-	}
-
-	if (image_create(&dec->gmc, dec->edged_width, dec->edged_height)) {
-		image_destroy(&dec->qtmp, dec->edged_width, dec->edged_height);
-		image_destroy(&dec->cur, dec->edged_width, dec->edged_height);
-		image_destroy(&dec->refn[0], dec->edged_width, dec->edged_height);
-		image_destroy(&dec->refn[1], dec->edged_width, dec->edged_height);
-		image_destroy(&dec->tmp, dec->edged_width, dec->edged_height);
-		xvid_free(dec);
-		return XVID_ERR_MEMORY;
-	}
+	if (   image_create(&dec->cur, dec->edged_width, dec->edged_height) 
+	    || image_create(&dec->refn[0], dec->edged_width, dec->edged_height)
+	    || image_create(&dec->refn[1], dec->edged_width, dec->edged_height) 	/* Support B-frame to reference last 2 frame */
+	    || image_create(&dec->tmp, dec->edged_width, dec->edged_height)
+	    || image_create(&dec->qtmp, dec->edged_width, dec->edged_height)
+      || image_create(&dec->gmc, dec->edged_width, dec->edged_height) )
+    goto memory_error;
 
 	dec->mbs =
 		xvid_malloc(sizeof(MACROBLOCK) * dec->mb_width * dec->mb_height,
 					CACHE_LINE);
-	if (dec->mbs == NULL) {
-		image_destroy(&dec->cur, dec->edged_width, dec->edged_height);
-		image_destroy(&dec->refn[0], dec->edged_width, dec->edged_height);
-		image_destroy(&dec->refn[1], dec->edged_width, dec->edged_height);
-		image_destroy(&dec->tmp, dec->edged_width, dec->edged_height);
-		image_destroy(&dec->qtmp, dec->edged_width, dec->edged_height);
-		xvid_free(dec);
-		return XVID_ERR_MEMORY;
-	}
+	if (dec->mbs == NULL)
+	  goto memory_error;
 	memset(dec->mbs, 0, sizeof(MACROBLOCK) * dec->mb_width * dec->mb_height);
 
 	/* For skip MB flag */
 	dec->last_mbs =
 		xvid_malloc(sizeof(MACROBLOCK) * dec->mb_width * dec->mb_height,
 					CACHE_LINE);
-	if (dec->last_mbs == NULL) {
-		xvid_free(dec->mbs);
-		image_destroy(&dec->cur, dec->edged_width, dec->edged_height);
-		image_destroy(&dec->refn[0], dec->edged_width, dec->edged_height);
-		image_destroy(&dec->refn[1], dec->edged_width, dec->edged_height);
-		image_destroy(&dec->tmp, dec->edged_width, dec->edged_height);
-		image_destroy(&dec->qtmp, dec->edged_width, dec->edged_height);
-		xvid_free(dec);
-		return XVID_ERR_MEMORY;
-	}
-
+	if (dec->last_mbs == NULL)
+	  goto memory_error;
 	memset(dec->last_mbs, 0, sizeof(MACROBLOCK) * dec->mb_width * dec->mb_height);
 
 	/* nothing happens if that fails */
@@ -171,6 +126,19 @@
 		memset(dec->qscale, 0, sizeof(int) * dec->mb_width * dec->mb_height);
 
 	return 0;
+
+memory_error:
+        /* Most structures were deallocated / nullifieded, so it should be safe */
+        /* decoder_destroy(dec) minus the write_timer */
+  xvid_free(dec->mbs);
+  image_destroy(&dec->cur, dec->edged_width, dec->edged_height);
+  image_destroy(&dec->refn[0], dec->edged_width, dec->edged_height);
+  image_destroy(&dec->refn[1], dec->edged_width, dec->edged_height);
+  image_destroy(&dec->tmp, dec->edged_width, dec->edged_height);
+  image_destroy(&dec->qtmp, dec->edged_width, dec->edged_height);
+
+  xvid_free(dec);
+  return XVID_ERR_MEMORY;
 }
 
 
@@ -475,6 +443,10 @@
 	CHECK_MV(mv[3]);
 }
 
+/* Up to this version, chroma rounding was wrong with qpel. 
+ * So we try to be backward compatible to avoid artifacts */
+#define BS_VERSION_BUGGY_CHROMA_ROUNDING 1
+
 /* decode an inter macroblock */
 static void
 decoder_mbinter(DECODER * dec,
@@ -510,8 +482,14 @@
 		uv_dx = mv[0].x;
 		uv_dy = mv[0].y;
 		if (dec->quarterpel) {
-			uv_dx /= 2;
-			uv_dy /= 2;
+			if (dec->bs_version <= BS_VERSION_BUGGY_CHROMA_ROUNDING) {
+				uv_dx = (uv_dx>>1) | (uv_dx&1);
+				uv_dy = (uv_dy>>1) | (uv_dy&1);
+			}
+			else {
+				uv_dx /= 2;
+				uv_dy /= 2;
+			}
 		}
 		uv_dx = (uv_dx >> 1) + roundtab_79[uv_dx & 0x3];
 		uv_dy = (uv_dy >> 1) + roundtab_79[uv_dy & 0x3];
@@ -527,8 +505,18 @@
 	} else {	/* MODE_INTER4V */
 
 		if(dec->quarterpel) {
-			uv_dx = (mv[0].x / 2) + (mv[1].x / 2) + (mv[2].x / 2) + (mv[3].x / 2);
-			uv_dy = (mv[0].y / 2) + (mv[1].y / 2) + (mv[2].y / 2) + (mv[3].y / 2);
+			if (dec->bs_version <= BS_VERSION_BUGGY_CHROMA_ROUNDING) {
+				int z;
+				uv_dx = 0; uv_dy = 0;
+				for (z = 0; z < 4; z++) {
+				  uv_dx += ((mv[z].x>>1) | (mv[z].x&1));
+				  uv_dy += ((mv[z].y>>1) | (mv[z].y&1));
+				}
+			}
+			else {
+				uv_dx = (mv[0].x / 2) + (mv[1].x / 2) + (mv[2].x / 2) + (mv[3].x / 2);
+				uv_dy = (mv[0].y / 2) + (mv[1].y / 2) + (mv[2].y / 2) + (mv[3].y / 2);
+			}
 		} else {
 			uv_dx = mv[0].x + mv[1].x + mv[2].x + mv[3].x;
 			uv_dy = mv[0].y + mv[1].y + mv[2].y + mv[3].y;
@@ -980,10 +968,18 @@
 		b_uv_dy = pMB->b_mvs[0].y;
 
 		if (dec->quarterpel) {
-			uv_dx /= 2;
-			uv_dy /= 2;
-			b_uv_dx /= 2;
-			b_uv_dy /= 2;
+			if (dec->bs_version <= BS_VERSION_BUGGY_CHROMA_ROUNDING) {
+				uv_dx = (uv_dx>>1) | (uv_dx&1);
+				uv_dy = (uv_dy>>1) | (uv_dy&1);
+				b_uv_dx = (b_uv_dx>>1) | (b_uv_dx&1);
+				b_uv_dy = (b_uv_dy>>1) | (b_uv_dy&1);
+			}
+			else {
+				uv_dx /= 2;
+				uv_dy /= 2;
+				b_uv_dx /= 2;
+				b_uv_dy /= 2;
+			}
 		}
 
 		uv_dx = (uv_dx >> 1) + roundtab_79[uv_dx & 0x3];
@@ -998,10 +994,18 @@
 		b_uv_dy = pMB->b_mvs[0].y + pMB->b_mvs[1].y + pMB->b_mvs[2].y + pMB->b_mvs[3].y;
 
 		if (dec->quarterpel) {
-			uv_dx /= 2;
-			uv_dy /= 2;
-			b_uv_dx /= 2;
-			b_uv_dy /= 2;
+			if (dec->bs_version <= BS_VERSION_BUGGY_CHROMA_ROUNDING) {
+				uv_dx = (uv_dx>>1) | (uv_dx&1);
+				uv_dy = (uv_dy>>1) | (uv_dy&1);
+				b_uv_dx = (b_uv_dx>>1) | (b_uv_dx&1);
+				b_uv_dy = (b_uv_dy>>1) | (b_uv_dy&1);
+			}
+			else {
+				uv_dx /= 2;
+				uv_dy /= 2;
+				b_uv_dx /= 2;
+				b_uv_dy /= 2;
+			}
 		}
 
 		uv_dx = (uv_dx >> 3) + roundtab_76[uv_dx & 0xf];
@@ -1155,7 +1159,7 @@
 			MACROBLOCK *mb = &dec->mbs[y * dec->mb_width + x];
 			MACROBLOCK *last_mb = &dec->last_mbs[y * dec->mb_width + x];
 			const int fcode_max = (fcode_forward>fcode_backward) ? fcode_forward : fcode_backward;
-			uint32_t intra_dc_threshold; /* fake variable */
+			int32_t intra_dc_threshold; /* fake variable */
 
 			if (check_resync_marker(bs, fcode_max  - 1)) {
 				int bound = read_video_packet_header(bs, dec, fcode_max - 1, &quant,