diff --git a/libavcodec/mjpegdec.c b/libavcodec/mjpegdec.c
index b439547..41df345 100644
--- a/libavcodec/mjpegdec.c
+++ b/libavcodec/mjpegdec.c
@@ -1374,9 +1374,15 @@ static int mjpeg_decode_app(MJpegDecodeContext *s)
             4bytes      field_size
             4bytes      field_size_less_padding
         */
+        int mode; /* 1 - ntsc, 2 - pal */
             s->buggy_avid = 1;
         i = get_bits(&s->gb, 8); len--;
         av_log(s->avctx, AV_LOG_DEBUG, "polarity %d\n", i);
+        skip_bits(&s->gb, 200);
+        mode = get_bits(&s->gb, 8);
+        if (mode == 1)
+            s->interlace_polarity = 1;
+        len -= 26;
 #if 0
         skip_bits(&s->gb, 8);
         skip_bits(&s->gb, 32);