[FFmpeg-trac] #10341(avcodec:new): [Caption] FFmpeg fails to decode closed-caption to srt/webvtt

[FFmpeg]

#10341: [Caption] FFmpeg fails to decode closed-caption to srt/webvtt
-------------------------------------+-------------------------------------
             Reporter:  Zied Aouina  |                    Owner:  (none)
                 Type:  defect       |                   Status:  new
             Priority:  important    |                Component:  avcodec
              Version:  git-master   |               Resolution:
             Keywords:  CLosed-      |               Blocked By:
  caption, eia-608, sub-rip          |
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------
Comment (by Zied Aouina):

 The issue was introduced starting from build n4.4:
 Here are the builds I compared (using the file I uploaded):
 https://sourceforge.net/projects/ffmpeg-windows-builds/files/release/

 Here is how n4.3.2 performs:
 ffmpeg.exe  -f lavfi -i movie=flvdecoder_input223-1.flv[out+subcc] -y
 -map 0:1  ./output_p.srt
 ffmpeg version n4.3.2-ffmpeg-windows-build-helpers Copyright (c) 2000-2021
 the FFmpeg developers
   built with gcc 10.2.0 (GCC)
   configuration: --pkg-config=pkg-config --pkg-config-flags=--static
 --extra-version=ffmpeg-windows-build-helpers --enable-version3 --disable-
 debug --disable-w32threads --arch=x86_64 --target-os=mingw32 --cross-
 prefix=/home/runner/work/ffmpeg-windows-builds/ffmpeg-windows-
 builds/sandbox/cross_compilers/mingw-w64-x86_64/bin/x86_64-w64-mingw32-
 --enable-libcaca --enable-gray --enable-libtesseract --enable-fontconfig
 --enable-gmp --enable-gnutls --enable-libass --enable-libbluray --enable-
 libbs2b --enable-libflite --enable-libfreetype --enable-libfribidi
 --enable-libgme --enable-libgsm --enable-libilbc --enable-libmodplug
 --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb
 --enable-libopus --enable-libsnappy --enable-libsoxr --enable-libspeex
 --enable-libtheora --enable-libtwolame --enable-libvo-amrwbenc --enable-
 libvorbis --enable-libwebp --enable-libzimg --enable-libzvbi --enable-
 libmysofa --enable-libopenjpeg --enable-libopenh264 --enable-liblensfun
 --enable-libvmaf --enable-libsrt --enable-demuxer=dash --enable-libxml2
 --enable-opengl --enable-libdav1d --enable-cuda-llvm --enable-libaom
 --enable-libvpx --enable-nvenc --enable-nvdec --extra-libs=-lharfbuzz
 --extra-libs=-lm --extra-libs=-lpthread --extra-cflags=-DLIBTWOLAME_STATIC
 --extra-cflags=-DMODPLUG_STATIC --extra-cflags=-DCACA_STATIC --enable-amf
 --enable-libmfx --enable-gpl --enable-frei0r --enable-filter=frei0r
 --enable-librubberband --enable-libvidstab --enable-libx264 --enable-
 libx265 --enable-avisynth --enable-libaribb24 --enable-libxvid --enable-
 libdavs2 --enable-libxavs2 --enable-libxavs --enable-avresample --extra-
 cflags='-mtune=generic' --extra-cflags=-O3 --enable-static --disable-
 shared --prefix=/home/runner/work/ffmpeg-windows-builds/ffmpeg-windows-
 builds/sandbox/cross_compilers/mingw-w64-x86_64/x86_64-w64-mingw32
   libavutil      56. 51.100 / 56. 51.100
   libavcodec     58. 91.100 / 58. 91.100
   libavformat    58. 45.100 / 58. 45.100
   libavdevice    58. 10.100 / 58. 10.100
   libavfilter     7. 85.100 /  7. 85.100
   libavresample   4.  0.  0 /  4.  0.  0
   libswscale      5.  7.100 /  5.  7.100
   libswresample   3.  7.100 /  3.  7.100
   libpostproc    55.  7.100 / 55.  7.100
 Input #0, lavfi, from 'movie=flvdecoder_input223-1.flv[out+subcc]':
   Duration: N/A, start: 0.000356, bitrate: N/A
     Stream #0:0: Video: rawvideo (I420 / 0x30323449), yuv420p, 1280x720
 [SAR 1:1 DAR 16:9], 29.97 fps, 29.97 tbr, 1k tbn, 1k tbc
     Stream #0:1: Subtitle: eia_608
 Output #0, srt, to './output_p.srt':
   Metadata:
     encoder         : Lavf58.45.100
     Stream #0:0: Subtitle: subrip (srt)
     Metadata:
       encoder         : Lavc58.91.100 srt
 Stream mapping:
   Stream #0:1 -> #0:0 (eia_608 (cc_dec) -> subrip (srt))
 Press [q] to stop, [?] for help
 [Parsed_movie_0 @ 0000023fe4cc0740] EOF timestamp not reliable
 size=       0kB time=00:00:00.02 bitrate= 106.7kbits/s speed=0.205x
 video:0kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB
 muxing overhead: 39.534885%
-- 
Ticket URL: <https://trac.ffmpeg.org/ticket/10341#comment:3>
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