diff --git a/libavcodec/h263.c b/libavcodec/h263.c
index 374c2d3cff..1a07b528bb 100644
--- a/libavcodec/h263.c
+++ b/libavcodec/h263.c
@@ -1130,6 +1130,8 @@ void h263_encode_mb(MpegEncContext * s,
                 s->misc_bits++;
                 s->last_bits++;
             }
+            s->skip_count++;
+
             return;
         }
         put_bits(&s->pb, 1, 0);	/* mb coded */
@@ -2032,7 +2034,7 @@ static void h263_encode_block(MpegEncContext * s, DCTELEM * block, int n)
         if (level == 128) //FIXME check rv10
             put_bits(&s->pb, 8, 0xff);
         else
-            put_bits(&s->pb, 8, level & 0xff);
+            put_bits(&s->pb, 8, level);
         i = 1;
     } else {
         i = 0;
@@ -2102,7 +2104,7 @@ static void h263_encode_block(MpegEncContext * s, DCTELEM * block, int n)
                 
                 assert(slevel != 0);
 
-                if(slevel < 128 && slevel > -128) 
+                if(level < 128) 
                     put_bits(&s->pb, 8, slevel & 0xff);
                 else{
                     put_bits(&s->pb, 8, 128);
@@ -2110,8 +2112,7 @@ static void h263_encode_block(MpegEncContext * s, DCTELEM * block, int n)
                     put_bits(&s->pb, 6, (slevel>>5)&0x3f);
                 }
               }else{
-                    if(slevel < 64 && slevel > -64) {
-                        /* 7-bit level */
+                if(level < 64) { // 7-bit level
                         put_bits(&s->pb, 1, 0);
                         put_bits(&s->pb, 1, last);
                         put_bits(&s->pb, 6, run);
diff --git a/libavcodec/mpegvideo.c b/libavcodec/mpegvideo.c
index ec29e4d8bf..b6720e0c88 100644
--- a/libavcodec/mpegvideo.c
+++ b/libavcodec/mpegvideo.c
@@ -3834,9 +3834,9 @@ static void encode_picture(MpegEncContext *s, int picture_number)
                 s->me.dia_size= s->avctx->pre_dia_size;
 
                 for(mb_y=s->mb_height-1; mb_y >=0 ; mb_y--) {
+                    s->mb_y = mb_y;
                     for(mb_x=s->mb_width-1; mb_x >=0 ; mb_x--) {
                         s->mb_x = mb_x;
-                        s->mb_y = mb_y;
                         ff_pre_estimate_p_frame_motion(s, mb_x, mb_y);
                     }
                 }
@@ -3846,13 +3846,13 @@ static void encode_picture(MpegEncContext *s, int picture_number)
 
         s->me.dia_size= s->avctx->dia_size;
         for(mb_y=0; mb_y < s->mb_height; mb_y++) {
+            s->mb_y = mb_y;
             s->block_index[0]= s->block_wrap[0]*(mb_y*2 + 1) - 1;
             s->block_index[1]= s->block_wrap[0]*(mb_y*2 + 1);
             s->block_index[2]= s->block_wrap[0]*(mb_y*2 + 2) - 1;
             s->block_index[3]= s->block_wrap[0]*(mb_y*2 + 2);
             for(mb_x=0; mb_x < s->mb_width; mb_x++) {
                 s->mb_x = mb_x;
-                s->mb_y = mb_y;
                 s->block_index[0]+=2;
                 s->block_index[1]+=2;
                 s->block_index[2]+=2;
@@ -3867,9 +3867,6 @@ static void encode_picture(MpegEncContext *s, int picture_number)
         }
     }else /* if(s->pict_type == I_TYPE) */{
         /* I-Frame */
-        //FIXME do we need to zero them?
-        memset(s->current_picture.motion_val[0][0], 0, sizeof(int16_t)*(s->mb_width*2 + 2)*(s->mb_height*2 + 2)*2);
-        memset(s->p_mv_table   , 0, sizeof(int16_t)*(s->mb_stride)*s->mb_height*2);
         for(i=0; i<s->mb_stride*s->mb_height; i++)
             s->mb_type[i]= CANDIDATE_MB_TYPE_INTRA;
         
@@ -4026,6 +4023,8 @@ static void encode_picture(MpegEncContext *s, int picture_number)
         break;
     case FMT_H264:
         break;
+    default:
+        assert(0);
     }
     bits= get_bit_count(&s->pb);
     s->header_bits= bits - s->last_bits;