[FFmpeg-devel] [PATCH] check that incoming data is identified as H.264

[Sean McGovern]

---
 libavcodec/h264_mp4toannexb_bsf.c |    8 +++++++-
 1 files changed, 7 insertions(+), 1 deletions(-)

diff --git a/libavcodec/h264_mp4toannexb_bsf.c b/libavcodec/h264_mp4toannexb_bsf.c
index d4a7f31..6b5ecb9 100644
--- a/libavcodec/h264_mp4toannexb_bsf.c
+++ b/libavcodec/h264_mp4toannexb_bsf.c
@@ -71,6 +71,12 @@ static int h264_mp4toannexb_filter(AVBitStreamFilterContext *bsfc,
         return 0;
     }
 
+    /* ensure incoming data is H.264 */
+    if(avctx->codec_id != CODEC_ID_H264 ||
+      avctx->codec_tag != AV_RL32("avc1")) {
+        return AVERROR(EINVAL);
+    }
+
     /* retrieve sps and pps NAL units from extradata */
     if (!ctx->extradata_parsed) {
         uint16_t unit_size;
@@ -114,7 +120,7 @@ static int h264_mp4toannexb_filter(AVBitStreamFilterContext *bsfc,
                 unit_nb = *extradata++; /* number of pps unit(s) */
         }
 
-        memset(out + total_size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
+        if(out) memset(out + total_size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
         av_free(avctx->extradata);
         avctx->extradata      = out;
         avctx->extradata_size = total_size;
-- 
1.7.4