Recherche avancée

Sur d’autres sites (21130)

• whats the difference between “&” and multiple terminals in Linux Multiprocessing [closed]

  11 mai 2022, par Ma XIaoyu

  I am using Linux for multi-task processing. Specifically, calling ffmpeg multiple times to transcoding multi source videos.

  


  Strangely, when I am using :
“
ffmpeg-cmds01 &
ffmpeg-cmds02 &
ffmpeg-cmds03 &
……
”
The ffmpeg process often get errors and stop after a few hours.

  


  However, if I open several terminals and using each terminal for only one ffmpeg cmd( i.e., terminal#1 only run ffmpeg-cmd01 ; ternimal#2 only for ffmpeg-cmd02, etc.) The transcoding procedure can last for dozens of days and no errors are reported.

  


  Could anyone kindly help us to analysis what’s there differences ? Opening multiple terminals is too difficult for managing especially when the number of video streams are up to 300+.

  


  Thanks a lot for help !

  


• Merge Audio and Video using ffmpeg - Python Lib [duplicate]

  15 janvier 2021, par badr

  i have tried

  


  import ffmpeg
video = ffmpeg.input('video.mp4')
audio = ffmpeg.input('audio.mp3')
ffmpeg.merge_outputs(video, audio).run()


  


  and it returns

  


  TypeError: Expected incoming stream(s) to be of one of the following types: ffmpeg.nodes.OutputStream; got <class>&#xA;</class>

  


  and i have tried

  


  import ffmpeg
video = ffmpeg.input('video.mp4')
audio = ffmpeg.input('audio.mp3')
ffmpeg.concat(video, audio, v=1, a=1).output('finished_video.mp4').run()


  


  and it returns

  


  FileNotFoundError: [WinError 2] The system cannot find the file specified


  


  also i did try

  


  import subprocess    
subprocess.run("ffmpeg -i video.mp4 -i audio.mp3 -c copy output.mp4")


  


  and it returns

  


  'ffmpeg' is not recognized as an internal or external command


  


  how can i do it right ?

  


• Why are there multiple .m3u8 requests made by the browser ?

  20 mai 2020, par 47fa0c

  I usually download my lectures instead of watching them on the online player provided by my university. I do this by finding requests that include .m3u8 in their url. There always seems to be two of these for each of the videos that I want to download, with one slight difference in the urls but otherwise identical. Why is that the case ?

  



  My wild guess is that one of them is supposed act as a backup if the other failed to fetch but I am not sure.

  



  I can't share the urls as they contain copyrighted material but it looks something like

  



  domain/a/b/hashedvalue1/c/video.mp4/index.m3u8


  



  and

  



  domain/a/b/hashedvalue2/c/video.mp4/index.m3u8


  



  Thanks for your help :)