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• Compiler Optimization flags for ffmpeg on Intel Xeon Phi

  10 octobre 2016, par Ambujam

  I am trying to compile ffmpeg on Xeon Phi processor. Are there any specific compiler optimization flags specific for Xeon Phi that I can enable while configuring ffmpeg so that I can achieve better performance in terms of encoder frames per second ?

  Encoder used : x264
  Operating System : CentOS 7.2
  Compiler : GCC 4.8.5

  Currently, I am configuring ffmpeg with the below command line :

  ./configure --prefix="$HOME/ffmpeg_build" 
  
  --extra-cflags="-I$HOME/ffmpeg_build/include" 
  
  --extra-ldflags="-L$HOME/ffmpeg_build/lib" --bindir="$HOME/bin" 
  
  --pkg-config-flags="--static" --enable-gpl --enable-nonfree 
  
  --enable-libx264

• Compiling and packging FFmpeg with special configuration

  1er septembre 2020, par Tnimni

  I need to compile FFmepg with specific configuration, that support nvidia cuda hardware acceleration.
In order to achive that, I'm compiling the code using the nvidia-cude-10.2 devel docker image.

  


  I want to take the files I compiled and move them to a python alpine docker after which.

  


  question is, if i follow the instructions here

  


  to be exact this part

  


  


     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" \
     --bindir="$HOME/bin" \
     --enable-gpl \
     --enable-gnutls \
     --enable-libaom \
     --enable-libass \
     --enable-libfdk-aac \
     --enable-libfreetype \
     --enable-libmp3lame \
     --enable-libopus \
     --enable-libvorbis \
     --enable-libvpx \
     --enable-libx264 \
     --enable-libx265 \
     --enable-nonfree && \
   PATH="$HOME/bin:$PATH" make && \
   make install && \
   hash -r


  


  


  and than copy the files in the $HOME/bin directory will it be enough ?

  


  Should I use cuda container instead of python alpine and install python on it ? I'm not sure if the cuda runtime is required after compilation

  


• Python subprocess.Popen + ffmpeg breaks terminal input

  16 décembre 2020, par Barney Suit

  I was writing a module to create random screenshots from a video and used subprocess.Popen to run multiple commands in parallel but this leads to terminal refusing from showing any input once the python program is finished running. But it still accepts most inputs given from the keyboard it just doesn't display it.

  


  Only if I type the reset command terminal starts working fine
This happened on ssh with putty and other ssh clients even ssh with powershell on windows and directly running on terminal with VNC

  


  But without ssh directly running the same command on windows ssh works fine and and inputs are visible

  


  here's a gif example for whats happening


  


  and code to replicate it

  


  #!/usr/bin/env python3.8
from subprocess import Popen

def create_screenshots():

    commands = ['ffmpeg -hide_banner -loglevel panic -ss 329  -i "/home/user/file.mkv" -y -vframes 1   "/home/user/file.329.frame.png"',
                'ffmpeg -hide_banner -loglevel panic -ss 312  -i "/home/user/file.mkv" -y -vframes 1   "/home/user/file.312.frame.png"',
                'ffmpeg -hide_banner -loglevel panic -ss 533  -i "/home/user/file.mkv" -y -vframes 1   "/home/user/file.533.frame.png"',
                'ffmpeg -hide_banner -loglevel panic -ss 444  -i "/home/user/file.mkv" -y -vframes 1   "/home/user/file.444.frame.png"',
                'ffmpeg -hide_banner -loglevel panic -ss 411  -i "/home/user/file.mkv" -y -vframes 1   "/home/user/file.411.frame.png"',
                'ffmpeg -hide_banner -loglevel panic -ss 413  -i "/home/user/file.mkv" -y -vframes 1   "/home/user/file.413.frame.png"']
    screenshot_files = []
    processes = [Popen(command, shell=True) for command in commands]
    for process in processes:
        process.wait()
    
    return screenshot_files


create_screenshots()