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• Image sequence to video stream ?

  15 novembre 2020, par Hauns TM

  Like many people already seem to have (there are several threads on this subject here) I am looking for ways to create video from a sequence of images.

  



  I want to implement my functionality in C# !

  



  Here is what I wan't to do :

  



  /*Pseudo code*/&#xA;void CreateVideo(List<image> imageSequence, long durationOfEachImageMs, string outputVideoFileName, string outputFormat)&#xA;{&#xA;    // Info: imageSequence.Count will be > 30 000 images&#xA;    // Info: durationOfEachImageMs will be &lt; 300 ms&#xA;&#xA;    if (outputFormat = "mpeg")&#xA;    {&#xA;    }&#xA;    else if (outputFormat = "avi")&#xA;    {      &#xA;    }&#xA;    else&#xA;    {&#xA;    }&#xA;&#xA;    //Save video file do disk&#xA;}&#xA;</image>

  



  I know there's a project called Splicer (http://splicer.codeplex.com/) but I can't find suitable documentation or clear examples that I can follow (these are the examples that I found).

  



  The closest I want to do, which I find here on CodePlex is this :
How can I create a video from a directory of images in C# ?

  



  I have also read a few threads about ffmpeg (for example this : C# and FFmpeg preferably without shell commands ? and this : convert image sequence using ffmpeg) but I find no one to help me with my problem and I don't think ffmpeg-command-line-style is the best solution for me (because of the amount of images).

  



  I believe that I can use the Splicer-project in some way (?).

  



  In my case, it is about about > 30 000 images where each image should be displayed for about 200 ms (in the videostream that I want to create).

  



  (What the video is about ? Plants growing ...)

  



  Can anyone help me complete my function ?

  


• subprocess Task fail after 8min when run inside Flask or BaseHTTPServer

  6 août 2015, par jthemovie

  I’m doing live HLS encoding with ffmpeg, and i usually run it via a python program as follow (i made some shortcuts...) :

  import subprocess
  
  
  
  def main():
  
      subprocess.Popen("ffmpeg -i .... (live hls encoding)", shell=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
  
  if __name__ == '__main__':
  
     main()

  And everything works like a charm, but when i use Flask or BaseHTTPServer, the very same weird behaviour occurs.

  After around 8min (more or less few seconds), the program stop responding and the encoding stop.

  import subprocess
  
  from flask import Flask, url_for, request, json, Response
  
  
  
  @app.route('/api/v2/livetv', methods = ['POST'])
  
  def api_live():
  
      subprocess.Popen("ffmpeg -i .... (live hls encoding)", shell=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
  
      return "-"
  
  
  
  if __name__ == '__main__':
  
     app.run(host='127.0.0.1', port=5001,debug=True)

  I tried using BaseHTTPServer, the very same behaviour occurs, it usually stop encoding after the segment number 46, or 47, which correspond at those 8 min.

  I have no idea why this behavior occurs. For example, the first script, once terminated, the ffmpeg will continue in background, while if i terminate the script with the web server, the ffmpeg program will exit as well.

  So if anyone could help me out with that, i would be more than glad.

  Thanks a lot for your help.

  Regards

  ps : if interested , my ffmpeg line look like this :

  /usr/bin/ffmpeg -user-agent "A User Agent" -headers "X-Forwarded-For:x.x.x.x"$’\r\n’ -re -i "http://..../index_2000_av-p.m3u8" -c:v libx264 -profile:v baseline -preset medium -x264opts level=41 -b:v 500k -s 600x340 -g 90 -bf 2 -c:a copy -f hls -hls_list_size 20 -hls_time 10 -hls_flags delete_segments -hls_segment_filename /var/www/livestream/"segment%03d.ts" /var/www/livestream/playlist.m3u8

• Add silence at the end of a .wav file created from a .mp4 using ffmpeg

  27 mars 2019, par Georgiana_M

  I want to generate .wav files from .mp4 ones using ffmpeg. In this command I want to include an option so that all the wav files have the same duration (add some seconds of silence at the end of each generated file).

  I saw here that you can add some options but they don’t seem to work in my case.

  This is what I have so far :

  command = "ffmpeg -i " + mp4_file_path + " -filter_complex [1:a][0:a]concat=n=2:v=0:a=1 -ab 160k -ac 1 -ar 44100 -vn " + wav_file_path
  
  
  
  subprocess.call(command, shell=True)