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• ffmpeg packet data from ts file

  16 avril 2013, par user2285642

  I am kinda new to ffmpeg, but did enough homework before posting this question. I have a ts file. I want to extract individual packets from it(both audio and video). I am able to generate output file using the below command

  ffmpeg.exe -i sample.ts -y -c copy -map p:1 output.h264

  However, this link is the closest to what I m looking for. ( He uses something called tsinfo.exe which is out of my scope).

  So, is there any way in ffmpeg to extract packet data from a ts file ?

  Anyone ?

  Thanks

• How to Create video from selected images of a folder using FFMPEG ?

  20 février 2018, par Hadley V Sunny

  For the time being I am doing

  ProcessStartInfo ffmpeg = new ProcessStartInfo();
  
  ffmpeg.CreateNoWindow = false;
  
  ffmpeg.UseShellExecute = false;
  
  
  
  ffmpeg.FileName = "e:\ffmpeg\ffmpeg.exe";
  
  ffmpeg.Arguments = "for file in (D:\\Day\\*.jpg); do ffmpeg -i \"$file\" -vf fps=1/60 -q:v 3 \"D:\\images\\out.mp4\"; done;";
  
  ffmpeg.RedirectStandardOutput = true;
  
  Process x = Process.Start(ffmpeg);

  Here I’m getting exception saying system cannot find specified file.
  For time being I’m considering all the files in D :\Day*.jpg but actually I need to query individual files from a list.

  Where am I wrong in the above scenario ?

• Creating an Init file from existing non-fragmented, segmented MP4 files

  20 novembre 2018, par slhck

  I am performing chunked encodes of longer video files, where I’ve split the original file into individual sequences that I have encoded separately. These sequences are files of different length, depending on where the scene cuts appear—they may be between 2 and 5 seconds long. They all start with an I-frame and are standalone.

  My encoded sequences are all MP4s, e.g. :

  test_0000.mp4
  
  test_0001.mp4
  
  test_0002.mp4
  
  test_0003.mp4
  
  test_0004.mp4

  They all have common properties :

  $ mp4info test_0000.mp4
  
  
  
  File:
  
    major brand:      isom
  
    minor version:    200
  
    compatible brand: isom
  
    compatible brand: iso2
  
    compatible brand: mp41
  
    fast start:       no
  
  
  
  Movie:
  
    duration:   2016 ms
  
    time scale: 1000
  
    fragments:  no
  
  
  
  ...

  Now, in order to play those with a DASH player, I have to create an initialization segment and individual fragmented MP4s.

  I could generate the fragmented MP4s via mp4fragment which I run on each standalone MP4 file :

  $ mp4info test_0000.m4s
  
  File:
  
    major brand:      isom
  
    minor version:    200
  
    compatible brand: isom
  
    compatible brand: iso2
  
    compatible brand: mp41
  
    compatible brand: iso5
  
    fast start:       yes
  
  
  
  Movie:
  
    duration:   2016 ms
  
    time scale: 1000
  
    fragments:  yes
  
  
  
  ...

  But obviously, these are now not according to spec, and all contain a moov atom :

  

  What I’d need is individual media segments with only one moof and mdat box, which then require an initialization segment with only a moov box.

  How can I generate that from the existing, already encoded segments ?

  I know this appears like an XY problem. In principle, I could already segment my original file directly after encoding, and run those encodes at the same time, e.g. using ffmpeg’s dash muxer, or MP4Box, however :

  • There is almost no control over the resulting segment sizes, with respect to minimum and maximum duration
  • This approach does not parallelize

  I have also checked Bento4 ; it does not seem to offer this functionality. Neither does FFmpeg. MP4Box behaves similarly. They all assume you have one long file to start with.

  ---

  I see I could splice off the ftyp and moov boxes from these “fake fragments” in order to create an initialization segment. But I would end up with segments containing multiple moof and mdat boxes, which is not according to the specification – it only allows one fragment and media data box :

  4. Media Segments

  […] one optional Segment Type Box (styp) followed by a single Movie Fragment Box (moof) followed by one or more Media Data Boxes (mdat).

  I guess I can live with this the styp not being present.