[FFmpeg-devel] Fix for KLV in mpegts

Artyom Lebedev vagran.ast at gmail.com
Fri Dec 7 12:06:36 EET 2018

This fixes bug which prevents from proper muxing-in KLV stream into mpeg-ts.


     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 *".

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