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• How do I increase the quality of a gif using ffmpeg from a web address [closed]

  1er août 2023, par Alteria

  I'm using command line/powershell on windows 11 along with ffmpeg to download gifs from web addresses. When I do this, though, the quality of the output is greatly decreased, even if the original file was itself a gif. Is there w way to fix this ?

  


  I'm doing this with .gif files, as well as .mp4 and .webm files using web links and addresses.

  


  The command I use is ffmpeg -i https://somewebsite.com/12345.gif "custom name.gif" when downloading gifs. The quality is always slightly decreased, and in some cases very decreased. I would like to keep this from happening. I also use the exact same command when downloading .gif's and .mp4's, with ffmpeg -i https//:somewebsite/123456.webm "custom name.gif" and ffmpeg -i https://somewebstie/123456.mp4 "custom name.gif" respectivly.

  


  What should I use instead of this in order to maintain the quality of the original .gif files and get better quality .gifs from the .webm and .mp4's ?

  


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  Some of the other answers I have looked for have not answered what to do with links, and the other example haven't worked either.

  


  The one-liner command ffmpeg -ss 23.0 -t 1.8 -i input.mp4 -filter_complex "[0:v] split [a][b];[a] palettegen [p];[b][p] paletteuse" output_trimmed_enhanced.gif supplied at banner-bear.com did not work, instead throwing an error 
*This specific example used a .gif file for the ffmpeg -i <file></file>, but the same error occurs when using .mp4's and .webm ;s

  


  I am also aware of the tool "gifski", posed by another user when they were asked a similar question on stack overflow (the question available here FFmpeg : high quality animated GIF ?). I would prefer to not download additional software in order to do what I wanted, so is there a way to circumvent this ?

  


  Edit

  


  I have found this forum post as one of the answers of this question : How do I convert a video to GIF using ffmpeg, with reasonable quality ?. This was the fourth (4th) answer down. This solution worked ! The command itself looks like this ffmpeg -i input.mp4 -filter_complex 'fps=10,scale=320:-1:flags=lanczos,split [o1] [o2];[o1] palettegen [p]; [o2] fifo [o3];[o3] [p] paletteuse' out.gif.

  


  I, however, have absolutely no idea how this command works. While this does work, I think it's going to be hard to remember this (and other) long commands. I want to be able to remember the commands as much as possible, and also to know what each part of it does. Is there an easier or shorter way of doing this command ? Or if not, what exactly does that command above do ?

  


  *I had seen palettegen and paletteuse when searching for the answer to this question, but I had a hard time understanding and following the documentation give on FFmpeg's Filter Documentation FFmpeg Filters Documentation, as well as other stack-overflow questions on these commands. Can someone show me coherent or simplified documentation for the problem I am trying to solve.

  


• How to create thumbnail using ffmpeg on linux server ? Guide to install ffmpeg on linux [on hold]

  6 avril 2019, par Manthan Kanani

  I am using fedora linux server cpanel. Im creating thumbnail in local environment with installing in windows. But this shell_exec command not running on linux server how to install ffmpeg and what should be the new code for different types of linux.
  After installing ffmpeg what should be the exec command for generate thumbnail...

• lavu/tx : do not unconditionally free subcontexts if initialization fails

  29 janvier 2022, par Lynne

  lavu/tx : do not unconditionally free subcontexts if initialization fails
  If a codelet initializes 2 subtransforms, and the second one fails,
  
  the failure would free all subcontexts.
  
  Instead, if there are subcontexts still left, don't free the array.
  
  If all initializations fail, the init() function will return,
  
  and reset_ctx() from the previous step will clean up all contained
  
  subtransforms.
  

  • [DH] libavutil/tx.c