[FFmpeg-trac] #3406(avcodec:open): H.264 threaded decode error

[FFmpeg]

#3406: H.264 threaded decode error
------------------------------------+-----------------------------------
             Reporter:  Cigaes      |                    Owner:
                 Type:  defect      |                   Status:  open
             Priority:  normal      |                Component:  avcodec
              Version:  git-master  |               Resolution:
             Keywords:  h264        |               Blocked By:
             Blocking:              |  Reproduced by developer:  1
Analyzed by developer:  0           |
------------------------------------+-----------------------------------
Changes (by cehoyos):

 * status:  new => open
 * reproduced:  0 => 1


Comment:

 Happens only rarely, helgrind still shows issues.
 {{{
 $ ffmpeg -i ../sf.h264 -f crc -vcodec png -
 ffmpeg version N-92703-gc6e1966 Copyright (c) 2000-2018 the FFmpeg
 developers
   built with gcc 8.2.1 (GCC) 20180813 (Advance-Toolchain-at12.0) [revision
 263510]
   configuration: --cpu=power7 --enable-gpl cc=/opt/at12.0/bin/gcc
   libavutil      56. 24.101 / 56. 24.101
   libavcodec     58. 42.101 / 58. 42.101
   libavformat    58. 24.101 / 58. 24.101
   libavdevice    58.  6.101 / 58.  6.101
   libavfilter     7. 46.101 /  7. 46.101
   libswscale      5.  4.100 /  5.  4.100
   libswresample   3.  4.100 /  3.  4.100
   libpostproc    55.  4.100 / 55.  4.100
 [h264 @ 0x10016471880] top block unavailable for requested intra mode -1
 [h264 @ 0x10016471880] error while decoding MB 19 0, bytestream 2784
 [h264 @ 0x10016471880] concealing 300 DC, 300 AC, 300 MV errors in I frame
 Input #0, h264, from '../sf.h264':
   Duration: N/A, bitrate: N/A
     Stream #0:0: Video: h264 (High 4:4:4 Predictive),
 yuv444p(progressive), 320x240 [SAR 1:1 DAR 4:3], 25 fps, 25 tbr, 1200k
 tbn, 50 tbc
 Stream mapping:
   Stream #0:0 -> #0:0 (h264 (native) -> png (native))
 Press [q] to stop, [?] for help
 [h264 @ 0x100164d26e0] top block unavailable for requested intra mode -1
 [h264 @ 0x100164d26e0] error while decoding MB 19 0, bytestream 2784
 [h264 @ 0x100164d26e0] concealing 300 DC, 300 AC, 300 MV errors in I frame
 [h264 @ 0x10016474210] error while decoding MB 2 14, bytestream -7
 [h264 @ 0x10016474210] concealing 67 DC, 67 AC, 67 MV errors in P frame
 [h264 @ 0x100164cbf10] error while decoding MB 18 13, bytestream -12
 [h264 @ 0x100164cbf10] concealing 71 DC, 71 AC, 71 MV errors in B frame
 [h264 @ 0x10016516a90] cabac decode of qscale diff failed at 14 13
 [h264 @ 0x10016516a90] error while decoding MB 14 13, bytestream 167
 [h264 @ 0x10016516a90] concealing 75 DC, 75 AC, 75 MV errors in B frame
 Output #0, crc, to 'pipe:':
   Metadata:
     encoder         : Lavf58.24.101
     Stream #0:0: Video: png, rgb24, 320x240 [SAR 1:1 DAR 4:3], q=2-31, 200
 kb/s, 25 fps, 25 tbn, 25 tbc
     Metadata:
       encoder         : Lavc58.42.101 png
 CRC=0xbbe0fd50
 frame=   12 fps=0.0 q=-0.0 Lsize=       0kB time=00:00:00.48 bitrate=
 0.2kbits/s speed=9.99x
 video:103kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB
 muxing overhead: unknown
 }}}
 {{{
 $ ffmpeg -i ../sf.h264 -f crc -vcodec png -
 ffmpeg version N-92703-gc6e1966 Copyright (c) 2000-2018 the FFmpeg
 developers
   built with gcc 8.2.1 (GCC) 20180813 (Advance-Toolchain-at12.0) [revision
 263510]
   configuration: --cpu=power7 --enable-gpl cc=/opt/at12.0/bin/gcc
   libavutil      56. 24.101 / 56. 24.101
   libavcodec     58. 42.101 / 58. 42.101
   libavformat    58. 24.101 / 58. 24.101
   libavdevice    58.  6.101 / 58.  6.101
   libavfilter     7. 46.101 /  7. 46.101
   libswscale      5.  4.100 /  5.  4.100
   libswresample   3.  4.100 /  3.  4.100
   libpostproc    55.  4.100 / 55.  4.100
 [h264 @ 0x1002fbb1880] top block unavailable for requested intra mode -1
 [h264 @ 0x1002fbb1880] error while decoding MB 19 0, bytestream 2784
 [h264 @ 0x1002fbb1880] concealing 300 DC, 300 AC, 300 MV errors in I frame
 Input #0, h264, from '../sf.h264':
   Duration: N/A, bitrate: N/A
     Stream #0:0: Video: h264 (High 4:4:4 Predictive),
 yuv444p(progressive), 320x240 [SAR 1:1 DAR 4:3], 25 fps, 25 tbr, 1200k
 tbn, 50 tbc
 Stream mapping:
   Stream #0:0 -> #0:0 (h264 (native) -> png (native))
 Press [q] to stop, [?] for help
 [h264 @ 0x1002fc126e0] top block unavailable for requested intra mode -1
 [h264 @ 0x1002fc126e0] error while decoding MB 19 0, bytestream 2784
 [h264 @ 0x1002fc126e0] concealing 300 DC, 300 AC, 300 MV errors in I frame
 [h264 @ 0x1002fbb4210] error while decoding MB 2 14, bytestream -7
 [h264 @ 0x1002fbb4210] concealing 67 DC, 67 AC, 67 MV errors in P frame
 [h264 @ 0x1002fc0bf10] error while decoding MB 18 13, bytestream -12
 [h264 @ 0x1002fc0bf10] concealing 71 DC, 71 AC, 71 MV errors in B frame
 [h264 @ 0x1002fc56a90] cabac decode of qscale diff failed at 14 13
 [h264 @ 0x1002fc56a90] error while decoding MB 14 13, bytestream 167
 [h264 @ 0x1002fc56a90] concealing 75 DC, 75 AC, 75 MV errors in B frame
 Output #0, crc, to 'pipe:':
   Metadata:
     encoder         : Lavf58.24.101
     Stream #0:0: Video: png, rgb24, 320x240 [SAR 1:1 DAR 4:3], q=2-31, 200
 kb/s, 25 fps, 25 tbn, 25 tbc
     Metadata:
       encoder         : Lavc58.42.101 png
 CRC=0x54a738a1
 frame=   12 fps=0.0 q=-0.0 Lsize=       0kB time=00:00:00.48 bitrate=
 0.2kbits/s speed=10.6x
 video:104kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB
 muxing overhead: unknown
 }}}

--
Ticket URL: <https://trac.ffmpeg.org/ticket/3406#comment:7>
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