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• ffmpeg - compositing a video within a video in the centre

  1er mars 2017, par kieran

  I’m looking to composite a video with ffmpeg that places the video in the centre no matter what the composited video’s aspect ratio/size.

  The "background" video will always be 16:9 and 1920x1080px. I won’t know the aspect ratio or size of the overlay video as it will be user uploaded and could be any size/ratio.

  Here’s an example of what I’m trying to achieve :

  This is the background image :

  

  Now I want to overlay a video over the top :

  

  This should also work :

  Essentially no matter what the dimensions I want to ensure it’s always resized to fit within 1920x1080 and in addition ensure it’s always centred.

  Finally, if the uploaded video is also 16:9 it should simply overlay the entire video :
  

• FFMPEG - Add (white, color-less, analog) grain to the video without desaturating video itself

  2 décembre 2018, par dd_code

  I am working on old videos where I am basically converting them to HVEC and sharpening, so i.e. my command can look like this

  .\ffmpeg.exe -i F:\file.mkv -vf unsharp=3:3:1.5 -c:v hevc_nvenc -qp 27 -a:c copy file_new.mkv

  inherent problem with this is, of course that with reducing bitrate and sharpening every now and then I can notice some nasty artifacts around the edges and on at plain-color objects.

  I noticed with some older, many times remastered movies/series that they have quite a lot of grain in the video, so I was thinking - what if I add grain and help it to mask the compression and sharpening artifacts ?

  After bit of searching I got to
  https://ffmpeg.org/ffmpeg-filters.html#noise
  and now I am using this command

  .\ffmpeg.exe -i F:\file.mkv -vf unsharp=3:3:1.5,noise=alls=14:allf=t+u -c:v hevc_nvenc -qp 30 -a:c copy file_new.mkv

  however this has one big problem, it is merely a digital RGB noise, is there a way to make it desaturated, analog-ish ? I tried adding h=s=0, however this is applying 0 saturation to the video track as a whole. Is there an effect which would achieve this or is there a way that I can reduce the saturation only of the very effect which then gets to "overlay" the video track, so the track would not be touched ?

• converting one video file to another video file with sound from ffmpeg using vc++2010 [closed]

  18 février 2013, par user2047514

  I am devloping a application that convert one video to another including sound (means in source file has video as well as sound) with the help of FFMPEG Librrary. I have created a video. But sound is not availabe in converted video. so please help me how can i fix this issue. I am sending You link .

  FFmpeg not honoring bitrate for different containers ?
  i have used this code for doing my work but sound is not availble. so please help my how can we handle this situation.

  Thanks for your cooperation
  Waiting your response.