avcodec/mpeg12dec: Do not choke on extra m704 alpha data

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
9 years ago · 390703fcf5
parent a67816bcce
commit 390703fcf5
1 changed files with 4 additions and 0 deletions
--- a/libavcodec/mpeg12dec.c
+++ b/libavcodec/mpeg12dec.c
@ -1896,6 +1896,10 @@ static int mpeg_decode_slice(MpegEncContext *s, int mb_y,
                        av_log(avctx, AV_LOG_DEBUG, "Invalid MXF data found in video stream\n");
                        is_d10 = 1;
                    }
+                    if (left > 32 && show_bits_long(&gb, 32) == 0x201) {
+                        av_log(avctx, AV_LOG_DEBUG, "skipping m704 alpha (unsupported)\n");
+                        goto eos;
+                    }
                }

                if (left < 0 ||