diff --git a/libavcodec/h264.c b/libavcodec/h264.c
index 604c29e273c74f060d693cdb9034d43a95200c98..62ee92090ae0f92a0eab9cf661b35f44850fdc84 100644
--- a/libavcodec/h264.c
+++ b/libavcodec/h264.c
@@ -2257,6 +2257,8 @@ static int decode_slice(struct AVCodecContext *avctx, void *arg){
                 ++s->mb_y;
                 if(FIELD_OR_MBAFF_PICTURE) {
                     ++s->mb_y;
+                    if(FRAME_MBAFF && s->mb_y < s->mb_height)
+                        predict_field_decoding_flag(h);
                 }
             }
 
@@ -2295,6 +2297,8 @@ static int decode_slice(struct AVCodecContext *avctx, void *arg){
                 ++s->mb_y;
                 if(FIELD_OR_MBAFF_PICTURE) {
                     ++s->mb_y;
+                    if(FRAME_MBAFF && s->mb_y < s->mb_height)
+                        predict_field_decoding_flag(h);
                 }
                 if(s->mb_y >= s->mb_height){
                     tprintf(s->avctx, "slice end %d %d\n", get_bits_count(&s->gb), s->gb.size_in_bits);
diff --git a/libavcodec/h264.h b/libavcodec/h264.h
index 2eec36309e0eff5bfd6a546eb2b77820982dd284..13a7b9b90ff873884e3bee8642d8e2466d2d6bdd 100644
--- a/libavcodec/h264.h
+++ b/libavcodec/h264.h
@@ -1453,7 +1453,7 @@ static inline int get_dct8x8_allowed(H264Context *h){
 
 static void predict_field_decoding_flag(H264Context *h){
     MpegEncContext * const s = &h->s;
-    const int mb_xy= h->mb_xy;
+    const int mb_xy= s->mb_x + s->mb_y*s->mb_stride;
     int mb_type = (h->slice_table[mb_xy-1] == h->slice_num)
                 ? s->current_picture.mb_type[mb_xy-1]
                 : (h->slice_table[mb_xy-s->mb_stride] == h->slice_num)
diff --git a/libavcodec/h264_cabac.c b/libavcodec/h264_cabac.c
index 45a96506afb80b336600a251d4d278d68a44ee44..147969781459c673faa2f919bf89fd304ffcd6e0 100644
--- a/libavcodec/h264_cabac.c
+++ b/libavcodec/h264_cabac.c
@@ -1196,8 +1196,6 @@ int ff_h264_decode_mb_cabac(H264Context *h) {
     if( h->slice_type_nos != FF_I_TYPE ) {
         int skip;
         /* a skipped mb needs the aff flag from the following mb */
-        if( FRAME_MBAFF && s->mb_x==0 && (s->mb_y&1)==0 )
-            predict_field_decoding_flag(h);
         if( FRAME_MBAFF && (s->mb_y&1)==1 && h->prev_mb_skipped )
             skip = h->next_mb_skipped;
         else
diff --git a/libavcodec/h264_cavlc.c b/libavcodec/h264_cavlc.c
index ee408050e474ac53eccd95d528e1076148c17e26..d83a306a5e3a17dd01c0a270c23be2c93eae7612 100644
--- a/libavcodec/h264_cavlc.c
+++ b/libavcodec/h264_cavlc.c
@@ -547,8 +547,6 @@ int ff_h264_decode_mb_cavlc(H264Context *h){
             if(FRAME_MBAFF && (s->mb_y&1) == 0){
                 if(s->mb_skip_run==0)
                     h->mb_mbaff = h->mb_field_decoding_flag = get_bits1(&s->gb);
-                else
-                    predict_field_decoding_flag(h);
             }
             decode_mb_skip(h);
             return 0;