Turn off VLC postprocessing
Posted: 18 Sep 2020 02:26
I've got a slideshow which I've turned into a lossless x264 video, but when I play it back on Windows the images are altered. Specifically, colors are muted (e.g. #000000 goes to #101010, #ffffff goes to #ebebeb) and some blur is added, which is most visible on non-antialiased curved sharp edges (the blur is somewhat similar to JPEG artifacts).
I'm fairly sure it's due to VLC doing some kind of postprocessing with the stream before rendering it. When I decode the video back into still images, they match pixel-for-pixel with the input, and when I take a screenshot with VLC's internal screenshot, it matches too. However, when I take a screenshot with a screenshot program outside VLC, the changes are obvious even when comparing visually. I'm also using the simplest possible means of encoding:
How do I turn this postprocessing off? (VLC 3.0.11, Win 7 x64)
The slideshow has a very low FPS, so I really doubt turning postprocessing off will have a negative impact on playback.
I'm fairly sure it's due to VLC doing some kind of postprocessing with the stream before rendering it. When I decode the video back into still images, they match pixel-for-pixel with the input, and when I take a screenshot with VLC's internal screenshot, it matches too. However, when I take a screenshot with a screenshot program outside VLC, the changes are obvious even when comparing visually. I'm also using the simplest possible means of encoding:
Code: Select all
$ ffmpeg -f image2 -r 1/7.5 -pattern_type glob -i 'image*.png' -c:v libx264 -crf 0 "${outputname}.mkv"
$ ffmpeg version 4.2.4 Copyright (c) 2000-2020 the FFmpeg developers
built with gcc 9 (GCC)
configuration: --prefix=/usr --bindir=/usr/bin --datadir=/usr/share/ffmpeg --docdir=/usr/share/doc/ffmpeg --incdir=/usr/include/ffmpeg --libdir=/usr/lib64 --mandir=/usr/share/man --arch=x86_64 --optflags='-O2 -g -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS -fexceptions -fstack-protector-strong -grecord-gcc-switches -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1 -m64 -mtune=generic -fasynchronous-unwind-tables -fstack-clash-protection -fcf-protection' --extra-ldflags='-Wl,-z,relro -Wl,--as-needed -Wl,-z,now -specs=/usr/lib/rpm/redhat/redhat-hardened-ld ' --extra-cflags=' ' --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libvo-amrwbenc --enable-version3 --enable-bzlib --disable-crystalhd --enable-fontconfig --enable-frei0r --enable-gcrypt --enable-gnutls --enable-ladspa --enable-libaom --enable-libdav1d --enable-libass --enable-libbluray --enable-libcdio --enable-libdrm --enable-libjack --enable-libfreetype --enable-libfribidi --enable-libgsm --enable-libmp3lame --enable-nvenc --enable-openal --enable-opencl --enable-opengl --enable-libopenjpeg --enable-libopus --enable-libpulse --enable-librsvg --enable-libsrt --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libvorbis --enable-libv4l2 --enable-libvidstab --enable-libvmaf --enable-version3 --enable-libvpx --enable-libx264 --enable-libx265 --enable-libxvid --enable-libzimg --enable-libzvbi --enable-avfilter --enable-avresample --enable-libmodplug --enable-postproc --enable-pthreads --disable-static --enable-shared --enable-gpl --disable-debug --disable-stripping --shlibdir=/usr/lib64 --enable-libmfx --enable-runtime-cpudetect
libavutil 56. 31.100 / 56. 31.100
libavcodec 58. 54.100 / 58. 54.100
libavformat 58. 29.100 / 58. 29.100
libavdevice 58. 8.100 / 58. 8.100
libavfilter 7. 57.100 / 7. 57.100
libavresample 4. 0. 0 / 4. 0. 0
libswscale 5. 5.100 / 5. 5.100
libswresample 3. 5.100 / 3. 5.100
libpostproc 55. 5.100 / 55. 5.100
Hyper fast Audio and Video encoder
usage: ffmpeg [options] [[infile options] -i infile]... {[outfile options] outfile}...
Use -h to get full help or, even better, run 'man ffmpeg'How do I turn this postprocessing off? (VLC 3.0.11, Win 7 x64)
The slideshow has a very low FPS, so I really doubt turning postprocessing off will have a negative impact on playback.