From 729ebb2f185244b0ff06d48edbbbbb02ceb4ed4e Mon Sep 17 00:00:00 2001 From: Janne Grunau Date: Mon, 19 Dec 2011 18:11:44 +0100 Subject: h264: clear trailing bits in partially parsed NAL units Trailing bits are likely to be non-zero if the NAL unit is truncated. Clearing the bits make overreads of the bitstream less likely in this case. Fixes playback of http://streams.videolan.org/streams/mp4/Mr_MrsSmith-h264_aac.mp4 which has a forbidden byte sequence of 0x00 0x00 0x00 in it SPS. --- libavcodec/h264.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/libavcodec/h264.c b/libavcodec/h264.c index 77acd7168f..a9a10513e3 100644 --- a/libavcodec/h264.c +++ b/libavcodec/h264.c @@ -3759,7 +3759,7 @@ static int decode_nal_units(H264Context *h, const uint8_t *buf, int buf_size){ int consumed; int dst_length; int bit_length; - const uint8_t *ptr; + uint8_t *ptr; int i, nalsize = 0; int err; @@ -3809,6 +3809,9 @@ static int decode_nal_units(H264Context *h, const uint8_t *buf, int buf_size){ } if (h->is_avc && (nalsize != consumed) && nalsize){ + // set trailing bits in the last partial byte to zero + if (bit_length & 7) + ptr[bit_length >> 3] = ptr[bit_length >> 3] & (0xff << 8 - (bit_length & 7)); av_log(h->s.avctx, AV_LOG_DEBUG, "AVC: Consumed only %d bytes instead of %d\n", consumed, nalsize); } -- cgit v1.2.3