[FFmpeg-trac] #7597(avformat:new): AV_PKT_DATA_MPEGTS_STREAM_ID is broken

FFmpeg trac at avcodec.org
Thu Dec 6 17:23:20 EET 2018

             Reporter:  vagran    |                     Type:  defect
               Status:  new       |                 Priority:  normal
            Component:  avformat  |                  Version:  git-master
             Keywords:  mpegts    |               Blocked By:
             Blocking:            |  Reproduced by developer:  0
Analyzed by developer:  0         |
 In current master (90ac0e5f29ba4730cd92d3268938b3730823e52b).
     char *side_data = NULL;
     int stream_id = -1;

     side_data = av_packet_get_side_data(pkt,
     if (side_data)
         stream_id = side_data[0];
 One-byte stream ID is read from "char *" array to integer making it to
 sign-extend which is not correct. Although it writes it correctly to
 stream, since it is treated as one byte again, but it fails with some
 condition checks, e.g. in mpegtsenc.c:1278:
 if (stream_id == 0xbd) /* asynchronous KLV */
     pts = dts = AV_NOPTS_VALUE;
 stream_id value in such case is 0xffffffbd.

 Fix should be changing side_data type from "char *" to "uint8_t *".

Ticket URL: <https://trac.ffmpeg.org/ticket/7597>
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