--- mbtransquant.c	2002/08/19 19:19:40	1.10
+++ mbtransquant.c	2002/09/23 20:36:02	1.11.2.1
@@ -68,7 +68,7 @@
 #define MIN(X, Y) ((X)<(Y)?(X):(Y))
 #define MAX(X, Y) ((X)>(Y)?(X):(Y))
 
-#define TOOSMALL_LIMIT 3		/* skip blocks having a coefficient sum below this value */
+#define TOOSMALL_LIMIT 	2	/* skip blocks having a coefficient sum below this value */
 
 /* this isnt pretty, but its better than 20 ifdefs */
 
@@ -105,7 +105,9 @@
 
 	start_timer();
 	pMB->field_dct = 0;
-	if ((frame->global_flags & XVID_INTERLACING)) {
+	if ((frame->global_flags & XVID_INTERLACING) &&
+		(x_pos>0) && (x_pos<pParam->mb_width-1) &&
+		(y_pos>0) && (y_pos<pParam->mb_height-1)) {
 		pMB->field_dct = MBDecideFieldDCT(data);
 	}
 	stop_interlacing_timer();
@@ -183,7 +185,9 @@
 
 	start_timer();
 	pMB->field_dct = 0;
-	if ((frame->global_flags & XVID_INTERLACING)) {
+	if ((frame->global_flags & XVID_INTERLACING) &&
+		(x_pos>0) && (x_pos<pParam->mb_width-1) &&
+		(y_pos>0) && (y_pos<pParam->mb_height-1)) {
 		pMB->field_dct = MBDecideFieldDCT(data);
 	}
 	stop_interlacing_timer();