[libav-bugs] [Bug 690] New: [H264]Multi-threads slice decoding causes SEGV

bugzilla at libav.org bugzilla at libav.org
Thu May 22 09:46:44 CEST 2014


http://bugzilla.libav.org/show_bug.cgi?id=690

           Summary: [H264]Multi-threads slice decoding causes SEGV
           Product: Libav
           Version: 9
          Platform: All
        OS/Version: Linux
            Status: NEW
          Severity: critical
          Priority: Normal
         Component: libavcodec
        AssignedTo: bugzilla at libav.org
        ReportedBy: fykcee1 at gmail.com


Created attachment 485
  --> http://bugzilla.libav.org/attachment.cgi?id=485
Related backtrace

We encode a h264 stream and send it through wireless net. On the other side,
there are PC and android pads(arm) receiving and decoding the stream.

Both PC and android pads encounter SEGV. The libav is shipped with gst-libav,
which is of version 9.13.

We also tried libav of version 10.1(shipped with master branch of gst-libav),
the problem continues.

The threading flag is THREAD_SLICE | THREAD_FRAME.

We tried to locate the point where the SEGV happened on PC, and there are two
places:
1. In mc_dir_part(h264.c)
pic_f.data may be NULL, and it crashed in 
line 505: qpix_op[luma_xy][dest_y, src_y, h->mb_linesize)

Attachment "pic_f_data_crash.bt.txt" is its backtrace.

2. In ff_h264_decode_mb_cabac(h264_cabac.c)
when (mb_type == 1) and (h->intra16x16_pred_mode == 255), it crashed in
hl_decode_mb_predict_luma(h264.c, line 1869) while making a call to
h->hpc.pred16x16[h->intra16x16_pred_mode](...)

Attachment "intra16x16_crash.bt.txt" is its backtrace.

-- 
Configure bugmail: http://bugzilla.libav.org/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are watching all bug changes.


More information about the libav-bugs mailing list