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• FFmpeg : How to split video to 2 equal chunks ?

  4 mai 2023, par Alon G

  I wish to split a large avi video into two smaller consecutive videos. I am using ffmpeg.

  


  I don't know what is the length of the video.

  


• Parsing split video with ffmpeg

  13 mai 2016, par mtomy

  I have video file split into few chunks. Split done and random file positions, but chunks are large enough.

  I need to parse every part with different instances of AVFormatContext. Chunks come one after another in right order. I think there are two options here :

  1. Being able to save and restore AVFormatContext state ;
  2. Save video file header (from first chunk) and attach it to every chunk.

  I tried both but no success. First approach requires to go too deeply beyond public API of ffmpeg. With second approach I am unable to merge header with new chunk so that ffmpeg can handle it.

  Can you help me with this ?

  Thank you.

• ffmpeg split videos from times in csv file

  10 juin 2018, par martins

  I’m using Python 3.6. I am trying to split videos into subclips of specified time. I have a folder with 250 ".mp4" files and a separate csv with the times at which I want each video to be subclipped. For instance, a first .mp4 file would be "firstvideo.mp4" up to "twohundredfiftyvideo.mp4". Separately, I have a csv file with each video file name in column A and the timing at which each video needs to be split (column B to I). All videos need to be split into 4 subclips. The .csv looks like :

          col A          col B      col C       colD      colE    .. colI
  
  row1 firstvideo.mp4  00:00:10 - 00:00:20 - 00:01:15 - 00:02:04 .. 00:07:15
  
  row2 secondvideo.mp4 00:00:15 - 00:00:34 - 00:01:05 - 00:01:55 .. 00:08:23

  "firstvideo.mp4" needs a first split from second 10 to 20, a second split from 1m15s - 2m04s and so on (colI is the time at which the fourth subclip should stop). The process should iterate for each of the 250 rows of the csv file corresponding to the 250 mp4 files in a folder.

  So far, the only thing I know is to use ffmpeg to split videos into 4 subclips and generate 4 different output files but do not know how to read from the csv line by line... This is the code I have so far.

  ffmpeg -i firstvideo.mp4 -vcodec copy -acodec copy -ss 00:00:10 -t 00:00:20
  
  firstvideo_1.mp4 -vcodec copy -acodec copy -ss 00:01:15 -t 00:02:04 firstvideo_2.mp4 -vcodec copy -acodec copy -ss 00:03:48 -t 00:04:23 
  
  firstvideo_3.mp4 -vcodec copy -acodec copy -ss 00:05:30 -t 00:07:15 firstvideo_4.mp4

  I name each output file with a _1,_2,_3 or _4 appended to the original video file name. Ideally, I would generate 4 subclips per video (i.e. 250 videos x 4subclip/video = 1,000 mp4 files) and then concatenate each video 4 subclips into one file (i.e. 250 additional files). In fact, I don’t care about the 4 subclips, I’d delete them after they generated my concatenated file.

  Thanks for your time anyways,