mpeg2: fix invalid interlaced frame in progressive sequence.

Some streams, badly constructed, could have signaled an interlaced
frame while the sequence was meant to be progressive. Warn and force
frame to be progressive in this case.

diff --git a/gst-libs/gst/vaapi/gstvaapidecoder_mpeg2.c b/gst-libs/gst/vaapi/gstvaapidecoder_mpeg2.c
index b2a6367..dbf66dd 100644 (file)
--- a/gst-libs/gst/vaapi/gstvaapidecoder_mpeg2.c
+++ b/gst-libs/gst/vaapi/gstvaapidecoder_mpeg2.c
@@ -577,6 +577,11 @@ decode_picture_ext(GstVaapiDecoderMpeg2 *decoder, guchar *buf, guint buf_size)
     }
     priv->has_pic_ext = TRUE;
 
+    if (priv->progressive_sequence && !pic_ext->progressive_frame) {
+        GST_WARNING("invalid interlaced frame in progressive sequence, fixing");
+        pic_ext->progressive_frame = 1;
+    }
+
     if (pic_ext->picture_structure == 0 ||
         (pic_ext->progressive_frame &&
          pic_ext->picture_structure != GST_MPEG_VIDEO_PICTURE_STRUCTURE_FRAME)) {