[FFmpeg-trac] #11405(undetermined:new): Seeking on real time transcoded AVCI 100 file fails.

Wed Jan 8 11:51:16 EET 2025

#11405: Seeking on real time transcoded AVCI 100 file fails.
-------------------------------------+-------------------------------------
             Reporter:  Ankur        |                     Type:  defect
  Bhatkalkar                         |
               Status:  new          |                 Priority:  normal
            Component:               |                  Version:
  undetermined                       |
             Keywords:               |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------
 == Summary of the bug:

 Our application requires some playback while recording for an AVC-I 100
 mxf file and I am facing this issue when running some local tests with
 ffmpeg. I run a transcode in real time which generates a growing mxf AVC-I
 100 file and in another terminal I use ffplay to try and seek to a
 position which is less than the duration that has been transcoded,
 playback from the beginning of the file works as expected, but seeking
 always fails with the clip always going to play from the beginning.

 == How to reproduce:

 This will require two terminals

 In the first terminal within any arbitrary directory enter this command (
 file has been attached for reference ), the input file should also be in
 this current directory

 {{{
 ffmpeg -re -v 9 -loglevel 99 -report -i PermA_BuckBunny_1080i50.mov -c:v
 libx264 -profile:v high422 -level:v 4.1 -b:v 100M -pix_fmt yuv422p10le
 -x264opts force-cfr:keyint=1:min-keyint=1:avcintra-class=100:nal-hrd=cbr
 -c:a pcm_s16le -ar 48000 -f mxf -write_index 1 output_avci.mxf
 }}}

 After the first command has run for more than 10s, open a second terminal
 and within the same directory enter( currently seeking to 10s but this
 could be any other value that works as long as it's within the duration
 that has been transcoded )

 {{{
 ffplay -v 9 -loglevel 99 -report -probesize 100G -ss 10 output_avci.mxf
 }}}

 The logs show the error for the seek every single time, tried a different
 range of options yet no success.

 {{{
 output_avci.mxf: could not seek to position 10.000
 }}}

 The ffmpeg and ffplay versions for the respective commands are( latest
 static builds were used for this ):

 {{{
 ./ffmpeg version
 ffmpeg version N-118247-g19c95ecbff-20250106 Copyright (c) 2000-2025 the
 FFmpeg developers
   built with gcc 14.2.0 (crosstool-NG 1.26.0.120_4d36f27)
   configuration: --prefix=/ffbuild/prefix --pkg-config-flags=--static
 --pkg-config=pkg-config --cross-prefix=x86_64-ffbuild-linux-gnu-
 --arch=x86_64 --target-os=linux --enable-gpl --enable-version3 --disable-
 debug --enable-iconv --enable-zlib --enable-libfreetype --enable-
 libfribidi --enable-gmp --enable-libxml2 --enable-openssl --enable-lzma
 --enable-fontconfig --enable-libharfbuzz --enable-libvorbis --enable-
 opencl --enable-libpulse --enable-libvmaf --enable-libxcb --enable-xlib
 --enable-amf --enable-libaom --enable-libaribb24 --enable-avisynth
 --enable-chromaprint --enable-libdav1d --enable-libdavs2 --enable-
 libdvdread --enable-libdvdnav --disable-libfdk-aac --enable-ffnvcodec
 --enable-cuda-llvm --enable-frei0r --enable-libgme --enable-libkvazaar
 --enable-libaribcaption --enable-libass --enable-libbluray --enable-libjxl
 --enable-libmp3lame --enable-libopus --enable-librist --enable-libssh
 --enable-libtheora --enable-libvpx --enable-libwebp --enable-libzmq
 --enable-lv2 --enable-libvpl --enable-openal --enable-libopencore-amrnb
 --enable-libopencore-amrwb --enable-libopenh264 --enable-libopenjpeg
 --enable-libopenmpt --enable-librav1e --enable-librubberband --disable-
 schannel --enable-sdl2 --enable-libsoxr --enable-libsrt --enable-libsvtav1
 --enable-libtwolame --enable-libuavs3d --enable-libdrm --enable-vaapi
 --enable-libvidstab --enable-vulkan --enable-libshaderc --enable-
 libplacebo --disable-libvvenc --enable-libx264 --enable-libx265 --enable-
 libxavs2 --enable-libxvid --enable-libzimg --enable-libzvbi --extra-
 cflags=-DLIBTWOLAME_STATIC --extra-cxxflags= --extra-libs='-ldl -lgomp'
 --extra-ldflags=-pthread --extra-ldexeflags=-pie --cc=x86_64-ffbuild-
 linux-gnu-gcc --cxx=x86_64-ffbuild-linux-gnu-g++ --ar=x86_64-ffbuild-
 linux-gnu-gcc-ar --ranlib=x86_64-ffbuild-linux-gnu-gcc-ranlib --nm=x86_64
 -ffbuild-linux-gnu-gcc-nm --extra-version=20250106
   libavutil      59. 54.101 / 59. 54.101
   libavcodec     61. 31.100 / 61. 31.100
   libavformat    61.  9.104 / 61.  9.104
   libavdevice    61.  4.100 / 61.  4.100
   libavfilter    10.  6.101 / 10.  6.101
   libswscale      8. 13.100 /  8. 13.100
   libswresample   5.  4.100 /  5.  4.100
   libpostproc    58.  4.100 / 58.  4.100
 }}}

 {{{
 ./ffplay version
 ffplay version N-118247-g19c95ecbff-20250106 Copyright (c) 2003-2025 the
 FFmpeg developers
   built with gcc 14.2.0 (crosstool-NG 1.26.0.120_4d36f27)
   configuration: --prefix=/ffbuild/prefix --pkg-config-flags=--static
 --pkg-config=pkg-config --cross-prefix=x86_64-ffbuild-linux-gnu-
 --arch=x86_64 --target-os=linux --enable-gpl --enable-version3 --disable-
 debug --enable-iconv --enable-zlib --enable-libfreetype --enable-
 libfribidi --enable-gmp --enable-libxml2 --enable-openssl --enable-lzma
 --enable-fontconfig --enable-libharfbuzz --enable-libvorbis --enable-
 opencl --enable-libpulse --enable-libvmaf --enable-libxcb --enable-xlib
 --enable-amf --enable-libaom --enable-libaribb24 --enable-avisynth
 --enable-chromaprint --enable-libdav1d --enable-libdavs2 --enable-
 libdvdread --enable-libdvdnav --disable-libfdk-aac --enable-ffnvcodec
 --enable-cuda-llvm --enable-frei0r --enable-libgme --enable-libkvazaar
 --enable-libaribcaption --enable-libass --enable-libbluray --enable-libjxl
 --enable-libmp3lame --enable-libopus --enable-librist --enable-libssh
 --enable-libtheora --enable-libvpx --enable-libwebp --enable-libzmq
 --enable-lv2 --enable-libvpl --enable-openal --enable-libopencore-amrnb
 --enable-libopencore-amrwb --enable-libopenh264 --enable-libopenjpeg
 --enable-libopenmpt --enable-librav1e --enable-librubberband --disable-
 schannel --enable-sdl2 --enable-libsoxr --enable-libsrt --enable-libsvtav1
 --enable-libtwolame --enable-libuavs3d --enable-libdrm --enable-vaapi
 --enable-libvidstab --enable-vulkan --enable-libshaderc --enable-
 libplacebo --disable-libvvenc --enable-libx264 --enable-libx265 --enable-
 libxavs2 --enable-libxvid --enable-libzimg --enable-libzvbi --extra-
 cflags=-DLIBTWOLAME_STATIC --extra-cxxflags= --extra-libs='-ldl -lgomp'
 --extra-ldflags=-pthread --extra-ldexeflags=-pie --cc=x86_64-ffbuild-
 linux-gnu-gcc --cxx=x86_64-ffbuild-linux-gnu-g++ --ar=x86_64-ffbuild-
 linux-gnu-gcc-ar --ranlib=x86_64-ffbuild-linux-gnu-gcc-ranlib --nm=x86_64
 -ffbuild-linux-gnu-gcc-nm --extra-version=20250106
   libavutil      59. 54.101 / 59. 54.101
   libavcodec     61. 31.100 / 61. 31.100
   libavformat    61.  9.104 / 61.  9.104
   libavdevice    61.  4.100 / 61.  4.100
   libavfilter    10.  6.101 / 10.  6.101
   libswscale      8. 13.100 /  8. 13.100
   libswresample   5.  4.100 /  5.  4.100
   libpostproc    58.  4.100 / 58.  4.100
 }}}

 Also attaching the ffmpeg and ffplay logs for when those commands were
 run.
-- 
Ticket URL: <https://trac.ffmpeg.org/ticket/11405>
FFmpeg <https://ffmpeg.org>
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