[FFmpeg-trac] #10173(avcodec:new): Lagarith decoder doesn't account null frames

[FFmpeg]

#10173: Lagarith decoder doesn't account null frames
-------------------------------------+-------------------------------------
             Reporter:  zxc          |                     Type:  defect
               Status:  new          |                 Priority:  normal
            Component:  avcodec      |                  Version:  git-
             Keywords:  lagarith,    |  master
  null frames                        |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------
 Summary of the bug: if the video is encoded with enabled null frames, they
 aren't decoded.
 ffmpeg correctly shows the duration (5s) of the attached file but decodes
 only 1 frame instead of 150.

 How to reproduce:
 {{{
 % ffmpeg -i "'07 - creditos.avi" -vf showinfo -f null -
 ffmpeg version N-109758-gbdc76f467f Copyright (c) 2000-2023 the FFmpeg
 developers
   built with gcc 12.2.1 (GCC) 20221004
   configuration: --enable-libzimg --enable-avisynth --enable-libbluray
 --extra-cflags='-march=core-avx2 -mtune=native -pipe -s -O2' --disable-
 debug --enable-gpl --cross-prefix=x86_64-w64-mingw32- --target-os=mingw32
 --arch=x86_64 --pkg-config-flags=--static --enable-zlib --disable-pthreads
 --enable-w32threads --enable-libfdk-aac --enable-libsoxr --enable-nonfree
   libavutil      57. 44.100 / 57. 44.100
   libavcodec     59. 63.100 / 59. 63.100
   libavformat    59. 38.100 / 59. 38.100
   libavdevice    59.  8.101 / 59.  8.101
   libavfilter     8. 56.100 /  8. 56.100
   libswscale      6.  8.112 /  6.  8.112
   libswresample   4.  9.100 /  4.  9.100
   libpostproc    56.  7.100 / 56.  7.100
 Input #0, avi, from 'C:\Users\xyz\Downloads\07 - creditos.avi':
   Duration: 00:00:05.00, start: 0.000000, bitrate: 154 kb/s
   Stream #0:0: Video: lagarith (LAGS / 0x5347414C), yuv420p, 1920x1080, 30
 fps, 30 tbr, 30 tbn
 Stream mapping:
   Stream #0:0 -> #0:0 (lagarith (native) -> wrapped_avframe (native))
 Press [q] to stop, [?] for help
 [Parsed_showinfo_0 @ 0000016f04945300] config in time_base: 1/30,
 frame_rate: 30/1
 [Parsed_showinfo_0 @ 0000016f04945300] config out time_base: 0/0,
 frame_rate: 0/0
 [Parsed_showinfo_0 @ 0000016f04945300] n:   0 pts:      0 pts_time:0
 duration:      1 duration_time:0.0333333 pos:     8212 fmt:yuv420p sar:0/1
 s:1920x1080 i:P iskey:1 type:I checksum:0135A388 plane_checksum:[A48AA81F
 9E571001 1ADBEB59] mean:[230 130 127] stdev:[27.3 8.0 8.0]
 [Parsed_showinfo_0 @ 0000016f04945300] color_range:unknown
 color_space:unknown color_primaries:unknown color_trc:unknown
 Output #0, null, to 'pipe:':
   Metadata:
     encoder         : Lavf59.38.100
   Stream #0:0: Video: wrapped_avframe, yuv420p(progressive), 1920x1080,
 q=2-31, 200 kb/s, 30 fps, 30 tbn
     Metadata:
       encoder         : Lavc59.63.100 wrapped_avframe
 frame=    0 fps=0.0 q=-0.0 size=       0kB time=00:00:00.00 bitrate=N/A
 speed=   0x
 frame=    1 fps=0.0 q=-0.0 Lsize=N/A time=00:00:00.00 bitrate=N/A speed=
 0x
 video:0kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB
 muxing overhead: unknown
 }}}
-- 
Ticket URL: <https://trac.ffmpeg.org/ticket/10173>
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