Recherche avancée

Sur d’autres sites (4978)

• Révision 20012 : réparer le flux rss des signatures cassé depuis http://zone.spip.org/trac/spip-z...

  17 novembre 2012, par b b

• Révision 20013 : report de r20012 : réparer le flux rss des signatures cassé depuis http://zone.s...

  17 novembre 2012, par b b

• Can you "stream" images to ffmpeg to construct a video, instead of saving them to disk ?

  8 juillet 2016, par Brandon

  My work recently involves programmatically making videos. In python, the typical workflow looks something like this :

  import subprocess, Image, ImageDraw
  
  
  
  for i in range(frames_per_second * video_duration_seconds):
  
      img = createFrame(i)
  
      img.save("%07d.png" % i)
  
  
  
  subprocess.call(["ffmpeg","-y","-r",str(frames_per_second),"-i", "%07d.png","-vcodec","mpeg4", "-qscale","5", "-r", str(frames_per_second), "video.avi"])

  This workflow creates an image for each frame in the video and saves it to disk. After all images have been saved, ffmpeg is called to construct a video from all of the images.

  Saving the images to disk (not the creation of the images in memory) consumes the majority of the cycles here, and does not appear to be necessary. Is there some way to perform the same function, but without saving the images to disk ? So, ffmpeg would be called and the images would be constructed and fed to ffmpeg immediately after being constructed.