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• ffmpeg - output images in memory instead of disk

  25 mai 2015, par Hyperion

  I’ve a python script which basically converts a video into images and stores them in a folder, then all this images are read and informations are extracted from them, then images are deleted. Since the writing images step is so slow and is apparently useless for what I need, I would like to store images somehow in memory instead of the disk, read this images from there and doing my operations, this would speed up my process a lot.

  Now my code look like :
  1st step :

  ffmpeg -i myvideo.avi -r 1 -f image2 C:\img_temp

  2nd step :

  for i in range(1, len(os.listdir(IMGTEMP)):
  
  #My operations for each image

  3rd step :

  for image in os.listdir(IMGTEMP):
  
          os.remove(IMGTEMP + "\\" + image)

• FFMPEG Extremely High Read On Disk When Transcoding

  19 mars 2024, par Jace Mayer

  I'm trying to use FFMPEG to transcode a h264 encoded file to mpegs, for use in streaming.

  


  The command used is :

  


  ffmpeg -v debug -re -i 'input.mkv' -acodec mp3 -f mpegts -


  


  Which is ran in a Python subprocess, and the output is streamed to the connected client over HTTP. I've tried mp4 encoding unsuccessfully, most likely due to the MOOV atom.

  


  The issue is, the ffmpeg process is reading terabytes of data for a less than 500mb file.

  


  I've tried changing the FFMPEG command to use different encoders. But, the high disk usage still occurs.

  


• Screenshot from video in memory without writing video or screenshot to disk

  28 février 2015, par user1401321

  I’m working on a application which processes a substantial quantity of video files. One of the processing steps involves creating a storyboard of the video contents by taking screenshots at certain points.

  Currently we are accomplishing this by writing the video from memory to disk, calling ffmpeg to generate a screenshot at a specified time, reading the screenshot to memory, then deleting both the video and screenshot from disk.

  The problem is that this is a substantial number of large disk operations, which are turning into a bottleneck.

  Ideally, what I’d like to do is to take the screenshots without ever writing the video or screenshot to disk ; The video is contained in memory at the time of processing, and all the videos have been transcoded to the mp4 format.

  Is there a way to accomplish this, with or without ffmpeg ?