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• FFmpeg video thumbnail colors look off (dull, faded, desaturated)

  21 juin 2022, par schneikai

  I try to generate video thumbnails with FFmpeg but the colors of the generated JPG file look very different from the video. Here is a screenshot I took while running the video in a player and the other picture is a JPG generated with FFmpeg. The video was recorded with an iPhone 12.

  


  Screenshot from Movie :

  


  

  


  Thumbnail from FFmpeg :

  


  

  


  Here´s a link to the mov-file : https://www.dropbox.com/s/udowplvfspxq6ag/IMG_8357.MOV?dl=1

  


  I use the following FFmpeg options : -y -vframes 1 -f image2

  


  My FFmpeg Version is

  


  ffmpeg version 5.0.1 Copyright (c) 2000-2022 the FFmpeg developers
built with Apple clang version 13.1.6 (clang-1316.0.21.2.5)
configuration: --prefix=/usr/local/Cellar/ffmpeg/5.0.1_1 --enable-shared --enable-pthreads --enable-version3 --cc=clang --host-cflags= --host-ldflags= --enable-ffplay --enable-gnutls --enable-gpl --enable-libaom --enable-libbluray --enable-libdav1d --enable-libmp3lame --enable-libopus --enable-librav1e --enable-librist --enable-librubberband --enable-libsnappy --enable-libsrt --enable-libtesseract --enable-libtheora --enable-libvidstab --enable-libvmaf --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libxvid --enable-lzma --enable-libfontconfig --enable-libfreetype --enable-frei0r --enable-libass --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libspeex --enable-libsoxr --enable-libzmq --enable-libzimg --disable-libjack --disable-indev=jack --enable-videotoolbox
libavutil      57. 17.100 / 57. 17.100
libavcodec     59. 18.100 / 59. 18.100
libavformat    59. 16.100 / 59. 16.100
libavdevice    59.  4.100 / 59.  4.100
libavfilter     8. 24.100 /  8. 24.100
libswscale      6.  4.100 /  6.  4.100
libswresample   4.  3.100 /  4.  3.100
libpostproc    56.  3.100 / 56.  3.100


  


  Thanks so much for pointing me in the right direction.

  


• ffmpeg, how to cut to exactly at the start and end time ? [closed]

  28 mars 2024, par Wayne Julian

  According to this article you can only cut the time, but not specify when to cut from the original video. So the end time will always be wrong. You need to calculate each time on the timeline when your video will end.

  


  e.g. -ss 01:30:40 -to 03:03:05 will cut your video in the wrong order, because it starting the calculation not from the 00:00:00 of the video, but from the -ss 01:30:40

  


  Is there a workaround for this ?

  


  example command :
ffmpeg -ss 00:14:15 -an -i  "2022-05-30.mp4" -to 01:30:40 -crf 23 -c:v libx264 PART1.mp4

  


  I will lose 14:15 minutes here, it is clearly a bug.
I need to extract 14:15 from the end time to get the correct time of the result video. When it comes to multiple video-editing it's so annoying.

  


• Use ffmpeg to convert FLAC to AAC using the aac_mf encoder

  19 juin 2022, par dstaley

  I'm using ffmpeg to convert audio from FLAC to AAC and I'd like to use the aac_mf encoder, which uses Microsoft Media Foundation. If I use the native AAC encoder built into ffmpeg it works with the following command :

  


  ffmpeg -i input.flac -acodec aac -vn output.m4a


  


  However, the following command gives an error :

  


  > ffmpeg -i input.flac -acodec aac_mf -vn output.m4a
ffmpeg version 5.0.1-full_build-www.gyan.dev Copyright (c) 2000-2022 the FFmpeg developers
  built with gcc 11.2.0 (Rev7, Built by MSYS2 project)
  configuration: --enable-gpl --enable-version3 --enable-static --disable-w32threads --disable-autodetect --enable-fontconfig --enable-iconv --enable-gnutls --enable-libxml2 --enable-gmp --enable-bzlib --enable-lzma --enable-libsnappy --enable-zlib --enable-librist --enable-libsrt --enable-libssh --enable-libzmq --enable-avisynth --enable-libbluray --enable-libcaca --enable-sdl2 --enable-libdav1d --enable-libdavs2 --enable-libuavs3d --enable-libzvbi --enable-librav1e --enable-libsvtav1 --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs2 --enable-libxvid --enable-libaom --enable-libopenjpeg --enable-libvpx --enable-mediafoundation --enable-libass --enable-frei0r --enable-libfreetype --enable-libfribidi --enable-liblensfun --enable-libvidstab --enable-libvmaf --enable-libzimg --enable-amf --enable-cuda-llvm --enable-cuvid --enable-ffnvcodec --enable-nvdec --enable-nvenc --enable-d3d11va --enable-dxva2 --enable-libmfx --enable-libshaderc --enable-vulkan --enable-libplacebo --enable-opencl --enable-libcdio --enable-libgme --enable-libmodplug --enable-libopenmpt --enable-libopencore-amrwb --enable-libmp3lame --enable-libshine --enable-libtheora --enable-libtwolame --enable-libvo-amrwbenc --enable-libilbc --enable-libgsm --enable-libopencore-amrnb --enable-libopus --enable-libspeex --enable-libvorbis --enable-ladspa --enable-libbs2b --enable-libflite --enable-libmysofa --enable-librubberband --enable-libsoxr --enable-chromaprint
  libavutil      57. 17.100 / 57. 17.100
  libavcodec     59. 18.100 / 59. 18.100
  libavformat    59. 16.100 / 59. 16.100
  libavdevice    59.  4.100 / 59.  4.100
  libavfilter     8. 24.100 /  8. 24.100
  libswscale      6.  4.100 /  6.  4.100
  libswresample   4.  3.100 /  4.  3.100
  libpostproc    56.  3.100 / 56.  3.100
Input #0, flac, from '.\input.flac':
  Duration: 00:04:09.17, start: 0.000000, bitrate: 833 kb/s
  Stream #0:0: Audio: flac, 44100 Hz, stereo, s16
Stream mapping:
  Stream #0:0 -> #0:0 (flac (native) -> aac (aac_mf))
Press [q] to stop, [?] for help
[aac_mf @ 000001bad81c6400] MFT name: 'Microsoft AAC Audio Encoder MFT'
[ipod @ 000001bad81fb640] track 0: codec frame size is not set
Output #0, ipod, to 'output.m4a':
  Stream #0:0: Audio: aac (mp4a / 0x6134706D), 44100 Hz, stereo, s16, 128 kb/s
    Metadata:
      encoder         : Lavc59.18.100 aac_mf
[aac_mf @ 000001bad81c6400] nb_samples (4096) != frame_size (0)
Audio encoding failed
Conversion failed!