Ensure that our total reference frame count does not exceed the SPS

max frame count, which is limited to less than the size of the
reference buffers, thereby preventing overflow.
Part of fix for issue 281.

Originally committed as revision 11216 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Jeff Downs 2007-12-14 06:25:23 +00:00
parent 41f7e2d11d
commit aeb59e839f
1 changed files with 23 additions and 0 deletions

View File

@ -3612,6 +3612,29 @@ static int execute_ref_pic_marking(H264Context *h, MMCO *mmco, int mmco_count){
s->current_picture_ptr->reference |= s->picture_structure;
}
if (h->sps.ref_frame_count &&
h->long_ref_count + h->short_ref_count == h->sps.ref_frame_count){
/* We have too many reference frames, probably due to corrupted
* stream. Need to discard one frame. Prevents overrun of the
* short_ref and long_ref buffers.
*/
av_log(h->s.avctx, AV_LOG_ERROR,
"number of reference frames exceeds max (probably "
"corrupt input), discarding one\n");
if (h->long_ref_count) {
for (i = 0; i < 16; ++i)
if (h->long_ref[i])
break;
assert(i < 16);
remove_long_at_index(h, i);
} else {
remove_short_at_index(h, h->short_ref_count - 1);
}
}
print_short_term(h);
print_long_term(h);
return 0;