diff --git a/libavcodec/mpeg12dec.c b/libavcodec/mpeg12dec.c
index 7525ee5c82..50cd8de760 100644
--- a/libavcodec/mpeg12dec.c
+++ b/libavcodec/mpeg12dec.c
@@ -2142,8 +2142,6 @@ static int mpeg1_decode_sequence(AVCodecContext *avctx,
         av_log(avctx, AV_LOG_ERROR, "Marker in sequence header missing\n");
         return AVERROR_INVALIDDATA;
     }
-    s->width  = width;
-    s->height = height;
 
     s->avctx->rc_buffer_size = get_bits(&s->gb, 10) * 1024 * 16;
     skip_bits(&s->gb, 1);
@@ -2175,6 +2173,9 @@ static int mpeg1_decode_sequence(AVCodecContext *avctx,
         return AVERROR_INVALIDDATA;
     }
 
+    s->width  = width;
+    s->height = height;
+
     /* We set MPEG-2 parameters so that it emulates MPEG-1. */
     s->progressive_sequence = 1;
     s->progressive_frame    = 1;