[FFmpeg-trac] #568(avcodec:open): H264 frame drop with the drop of one slice / visible artefacts that do not happen with the reference decoder (was: H264 frame drop with the drop of one slice)

[FFmpeg]

#568: H264 frame drop with the drop of one slice / visible artefacts that do not
happen with the reference decoder
--------------------------------------+-----------------------------------
             Reporter:  hardiksharma  |                    Owner:  michael
                 Type:  defect        |                   Status:  open
             Priority:  normal        |                Component:  avcodec
              Version:  git-master    |               Resolution:
             Keywords:                |               Blocked By:
             Blocking:                |  Reproduced by developer:  1
Analyzed by developer:  0             |
--------------------------------------+-----------------------------------
Changes (by cehoyos):

 * status:  new => open
 * version:  unspecified => git-master
 * component:  FFmpeg => avcodec
 * reproduced:  0 => 1


Comment:

 Complete, uncut output of the failing command missing (please consider
 using Code block) and please mention how you patched FFmpeg for your test
 (git diff >slices.diff and attach slices.diff).

 I can decode the first 39 frames of the sample with the reference decoder
 and while FFmpeg decodes the same 39 frames, only the first three and the
 last 20 (beginning with the second IDR frame) are bit-exact, the remaining
 16 show visible artefacts with FFmpeg (that are not reproducible with the
 reference decoder).
 {{{
 $ ffmpeg -i error_51.264 -t 1.25 -f framecrc outff
 ffmpeg version N-33734-g1de357d, Copyright (c) 2000-2011 the FFmpeg
 developers
   built on Oct 18 2011 00:33:06 with gcc 4.5.3
   configuration: --cc=/usr/local/gcc-4.5.3/bin/gcc
   libavutil    51. 21. 0 / 51. 21. 0
   libavcodec   53. 21. 0 / 53. 21. 0
   libavformat  53. 16. 0 / 53. 16. 0
   libavdevice  53.  4. 0 / 53.  4. 0
   libavfilter   2. 43. 6 /  2. 43. 6
   libswscale    2.  1. 0 /  2.  1. 0
 [h264 @ 0x1306c00] concealing 47 DC, 47 AC, 47 MV errors
 [h264 @ 0x1306c00] Missing reference picture
     Last message repeated 13 times
 [h264 @ 0x1300780] max_analyze_duration 5000000 reached at 5000000
 [h264 @ 0x1300780] Estimating duration from bitrate, this may be
 inaccurate

 Seems stream 0 codec frame rate differs from container frame rate: 60.00
 (60/1) -> 30.00 (60/2)
 Input #0, h264, from 'error_51.264':
   Duration: N/A, bitrate: N/A
     Stream #0:0: Video: h264 (High), yuv420p, 352x288, 30 fps, 30 tbr,
 1200k tbn, 60 tbc
 [buffer @ 0x1308d60] w:352 h:288 pixfmt:yuv420p tb:1/1000000 sar:0/1
 sws_param:
 Output #0, framecrc, to 'outff':
   Metadata:
     encoder         : Lavf53.16.0
     Stream #0:0: Video: rawvideo (I420 / 0x30323449), yuv420p, 352x288,
 q=2-31, 200 kb/s, 90k tbn, 30 tbc
 Stream mapping:
   Stream #0.0 -> #0.0 (h264 -> rawvideo)
 Press [q] to stop, [?] for help
 [h264 @ 0x1306c00] concealing 47 DC, 47 AC, 47 MV errors
 [h264 @ 0x1306c00] Missing reference picture
     Last message repeated 50 times
 frame=   39 fps=  0 q=0.0 Lsize=       1kB time=00:00:01.30 bitrate=
 6.9kbits/s
 video:5792kB audio:0kB global headers:0kB muxing overhead -99.980963%
 }}}
 {{{
 $ diff -uw outjm outff
 --- outjm       2011-10-18 00:02:15.900762160 +0200
 +++ outff       2011-10-18 00:01:07.655762411 +0200
 @@ -1,22 +1,22 @@
  0, 0, 152064, 0x653f8f51
  0, 3000, 152064, 0x112eaae5
  0, 6000, 152064, 0x5c3e3dc5
 -0, 9000, 152064, 0x6c6e0c46
 -0, 12000, 152064, 0x1df99fad
 -0, 15000, 152064, 0xfc99c44d
 -0, 18000, 152064, 0x173f883f
 -0, 21000, 152064, 0x2f4ec859
 -0, 24000, 152064, 0xf90d56d4
 -0, 27000, 152064, 0x9e641e1d
 -0, 30000, 152064, 0x355b78b2
 -0, 33000, 152064, 0x32751de8
 -0, 36000, 152064, 0xb4f1c60e
 -0, 39000, 152064, 0xa9431da3
 -0, 42000, 152064, 0x4489996f
 -0, 45000, 152064, 0x3d2a7b4c
 -0, 48000, 152064, 0xc9d1fbb6
 -0, 51000, 152064, 0xbd9cc699
 -0, 54000, 152064, 0x8a6ae1ea
 +0, 9000, 152064, 0x0615eae0
 +0, 12000, 152064, 0xaad687d7
 +0, 15000, 152064, 0xe0c10d04
 +0, 18000, 152064, 0x19a9814f
 +0, 21000, 152064, 0xf1528f3a
 +0, 24000, 152064, 0x57ff4c9e
 +0, 27000, 152064, 0xd0ab6ed9
 +0, 30000, 152064, 0x631efdc4
 +0, 33000, 152064, 0xba305bf0
 +0, 36000, 152064, 0xe81e357b
 +0, 39000, 152064, 0xc192951e
 +0, 42000, 152064, 0x6182c0ff
 +0, 45000, 152064, 0x730500cb
 +0, 48000, 152064, 0x6d1b7fcb
 +0, 51000, 152064, 0xdd688063
 +0, 54000, 152064, 0xe560656a
  0, 57000, 152064, 0x9e7b0ae6
  0, 60000, 152064, 0x3eb31b79
  0, 63000, 152064, 0xf01c6764
 }}}

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Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/568#comment:1>
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