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• How to stitch videos to one 360 video without 3rd party software ?

  6 janvier 2017, par Basset hound

  I am using a 3D software, something like GTA.
  I wanted to create a 360 video.
  What I did was create 84 videos automatically by C#.
  
  Set camera orientation to, (Step = 30 degree)
  

  1. (Rx, Ry, Rz) = (0.0, -90.0, 0.0)
  
  2. (Rx, Ry, Rz) = (0.0, -90.0, 30.0)
  
  3. (Rx, Ry, Rz) = (0.0, -90.0, 60.0)
  
  ...
  
  12. (Rx, Ry, Rz) = (0.0, -90.0, 330.0) 
  
  
  
  13. (Rx, Ry, Rz) = (0.0, -60.0, 0.0) 
  
  14. (Rx, Ry, Rz) = (0.0, -60.0, 30.0)
  
  15. (Rx, Ry, Rz) = (0.0, -60.0, 60.0) 
  
  ...
  
  83. (Rx, Ry, Rz) = (0.0, 90.0, 300.0) 
  
  84. (Rx, Ry, Rz) = (0.0, 90.0, 330.0) 

  After created 84 videos, I used Kolor Autopano Video to stitch the video.
  The result is good.
  
  However, I was wondering, each video has precise camera orientation.
  I think I don’t really need Kolor Autopano Video to create 360 video.
  Is it possible to stitch 84 videos by FFmpeg or C# ?
  Do you have any hint about this ?
  
  Thank you.

• stitching two videos into one using FFMPEG

  30 juillet 2015, par nikhil khare

  I am using FFmpeg to concatenate two videos. I use demuxer option like this.
  Created a file using following text.

  file '/var/www/html/test/input/video1.mp4'
  
  file '/var/www/html/test/input/video2.mp4'

  The codec, bit-rate and aspect ratio are same for both the videos. Now I use this command to generate the output

  ffmpeg -f concat -i mylist.txt -c copy merged.mp4

  It creates the output file with merging the videos but, when i position the seek button to any time it stops playing. The total video duration is also a lot more than the actual video duration.

  It also does not show the second video after the first video is finished. It keeps the last frame through out the video.

  I have found somewhere to mention the duration in the text file, but I am not able to implement it. Please help.

• How to concat videos that have different colour spaces ?

  17 avril 2023, par Ham789

  I writing a Python program that uses subprocess to automate ffmpeg. The program concatenates many videos together with the concat filter. The problem I have is that the colour of some of the videos is very washed out in the final output. I believe this is because the videos have different colour spaces. Some are B.709 and some are B.2020. The B.2020 videos are washed out.

  


  I have tried converting the B.2020 videos to B.709 before concatenating by using the following command on each video but the outputs are still washed out :

  


  ffmpeg -i input.mov -vf colorspace=all=bt709:iall=bt2020:fast=1 output.mov


  


  It wasn't clear to me which way round the arguments should go so I also tried switching the bt2020 and bt709 terms but they still look washed out but with more saturation.

  


  Is this the right approach ? Am I missing some other arguments in order to convert the B.2020 videos to B.709 while preserving their colour ?

  


  I have attached a side by side of the original and converted video.

  


  The metadata of the videos I am trying to concat are :

  


  Video 1

  


  

  • color_range=tv

  


  • color_space=bt709

  


  • color_transfer=bt709

  


  • color_primaries=bt709

  


  


  Video 2

  


  

  • color_range=tv

  


  • color_space=bt2020nc

  


  • color_transfer=arib-std-b67

  


  • color_primaries=bt2020