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• ffmpeg minimal linux build with only one filter [closed]

  31 juillet 2024, par at8993

  I am aiming to compile a minimal build of ffmpeg for Ubuntu 22.04. The application requires only the concat filter for .mp4s using H.264 video encoder.

  


  I have followed this guide and used the following commands to include libx264 only :

  


  sudo apt-get update -qq && sudo apt-get -y install \
  autoconf \
  automake \
  build-essential \
  cmake \
  git-core \
  libass-dev \
  libfreetype6-dev \
  libgnutls28-dev \
  libmp3lame-dev \
  libsdl2-dev \
  libtool \
  libva-dev \
  libvdpau-dev \
  libvorbis-dev \
  libxcb1-dev \
  libxcb-shm0-dev \
  libxcb-xfixes0-dev \
  meson \
  ninja-build \
  pkg-config \
  texinfo \
  wget \
  yasm \
  zlib1g-dev

mkdir -p ~/ffmpeg_sources ~/bin

sudo apt-get install libx264-dev


  


  and for the configure command I have used the following options with a view to only enable what's necessary for concat.

  


  cd ~/ffmpeg_sources && \
wget -O ffmpeg-snapshot.tar.bz2 https://ffmpeg.org/releases/ffmpeg-snapshot.tar.bz2 && \
tar xjvf ffmpeg-snapshot.tar.bz2 && \
cd ffmpeg && \

PATH="$HOME/bin:$PATH" PKG_CONFIG_PATH="$HOME/ffmpeg_build/lib/pkgconfig" ./configure \
  --prefix="$HOME/ffmpeg_build" \
  --pkg-config-flags="--static" \
  --extra-cflags="-I$HOME/ffmpeg_build/include" \
  --extra-ldflags="-L$HOME/ffmpeg_build/lib" \
  --extra-libs="-lpthread -lm" \
  --ld="g++" \
  --bindir="$HOME/bin" \
  --disable-everything \
  --enable-filter=concat \
  --enable-avformat \
  --enable-avdevice \
  --enable-avcodec \
  --enable-decoder=h264 
  --enable-libx264 
  --enable-muxer=mp4 
  --enable-gpl

PATH="$HOME/bin:$PATH" make && \
make install && \
hash -r


  


  However running

  


  ffmpeg -f concat -i files_to_merge.txt -c copy output.mp4


  


  returns error

  


  ffmpeg -f concat -i files_to_merge.txt -c copy output.mp4
ffmpeg version N-116445-gb1d410716b Copyright (c) 2000-2024 the FFmpeg developers
  built with gcc 11 (Ubuntu 11.4.0-1ubuntu1~22.04)
  configuration: --prefix=/home/user/ffmpeg_build 
--extra-cflags=-I/home/user/ffmpeg_build/include --extra-ldflags=-L/home/user/ffmpeg_build/lib 
--extra-libs='-lpthread -lm' 
--ld=g++ --bindir=/home/user/bin --disable-everything 
--enable-filter=concat --enable-avformat 
--enable-avdevice --enable-avcodec --enable-decoder=h264
 --enable-libx264 --enable-muxer=mp4 
--enable-gpl
  libavutil      59. 30.100 / 59. 30.100
  libavcodec     61. 10.100 / 61. 10.100
  libavformat    61.  5.101 / 61.  5.101
  libavdevice    61.  2.100 / 61.  2.100
  libavfilter    10.  2.102 / 10.  2.102
  libswscale      8.  2.100 /  8.  2.100
  libswresample   5.  2.100 /  5.  2.100
  libpostproc    58.  2.100 / 58.  2.100
[in#0 @ 0x555605fab640] Unknown input format: 'concat'


  


  I assume this is due to the omission of an enable option in the configure command.

  


  Thanks !

  


• Deobfuscation Redux : JavaScript

  20 juin 2011, par Multimedia Mike — Reverse Engineering, deobfuscation, javascript, programming

  Google recently released version 12 of their Chrome browser. This version adds a new feature that automatically allows deobfuscating obfuscated JavaScript source code.

  Before :

  
  
  

  After :

  
  
  

  As a reverse engineering purist, I was a bit annoyed. Not at the feature, just the naming. This is clearly code beautification but not necessarily deobfuscation. The real obfuscation comes not from removing whitespace but from renaming variable and function names to terse 1- and 2-letter identifiers. True automated deobfuscation — which entails recovering the original variable and function identifiers as well as source code comments — is basically impossible.

  Still, it makes me wonder if there is any interest in a JavaScript deobfuscator that operates similar to my Java deobfuscator which was one of the first things I published on this blog. The general idea is automatically replace function names with random English verbs (since functions correspond to actions) and variable names with random animal names (I decided "English nouns" encompassed too broad a category of words). I suspect the day that someone releases a proprietary multimedia codec in a pure (though obfuscated) JavaScript format is that day that I will try to accomplish this, if it hasn’t been done already.

  See also :

  • Success on the Java De-obfuscation Front

• How fade-in and fade-out an overlay image on a video and repeat after every 15s

  20 juin 2018, par Adam Estel

  I have code that fade-in 2s and fade-out 3s and overlay image on a video :

  ffmpeg -f lavfi -i video.mp4 -loop 1 -i logo.png -filter_complex "[1:0] format=rgba,fade=in:st=0:d=2:alpha=1,fade=out:st=6:d=3:alpha=1 [ovr];[0:0][ovr] overlay=0:0" -t 10 -y out.mp4

  I want to repeat fade-in and fade-out effects after every 15 seconds.Is it possible with ffmpeg ?
  I tried variety methods but "Fade" filter only apply specific frame(or time) not variable.
  Sorry for my bad english.