typo

Originally committed as revision 4006 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/mpeg12.c

@@ -2150,7 +2150,7 @@ static void mpeg_decode_sequence_extension(Mpeg1Context *s1)
     s->width |= (horiz_size_ext << 12);
     s->height |= (vert_size_ext << 12);
     bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
-    s->bit_rate += (bit_rate_ext << 12) * 400;
+    s->bit_rate += (bit_rate_ext << 18) * 400;
     skip_bits1(&s->gb); /* marker */
     s->avctx->rc_buffer_size += get_bits(&s->gb, 8)*1024*16<<10;