Recherche avancée

Sur d’autres sites (14846)

• How to increase resolution in ffmpeg with rawvideo [closed]

  2 novembre 2020, par Jamie Hutber

  I am using my DSLR with loopback to use as a webcam, however the resolution is locked at 640x426 and I cannot seem to find a way to make this larger as the stream itself is 1080p from the camera.

  


  sudo modprobe v4l2loopback video_nr=2 exclusive_caps=1,1,1 card_label='Screenshare' && gphoto2 --stdout --capture-movie | ffmpeg -i - -vcodec rawvideo -pix_fmt yuv420p -threads 0 -f v4l2 /dev/video2


  


• How can I upscale videos with FFmpeg to a fixed resolution ?

  30 juillet 2020, par Tobias

  Resolution of an example video : 640x788

  


  Desired resolution of the new video : 1920x1080

  


  The aspect ratio of the video should be kept (the area left & right should be filled black).

  


  My current call looks like this : ffmpeg -i input.mp4 -s 1920x1080 -r 60 -aspect 1:1 -strict experimental output.mp4. The problem here is that the video is sometimes made narrower / wider (aspect ratio is not kept).

  


  Since I am no FFmpeg expert I hope for help here (maybe there is a padding property ?)

  


• check media resolution, if resolution is big ffmpeg it, if output is smaller than original delete the original else delete the output

  13 avril 2015, par The Wolf

  I have my storage VPS filled with videos, and hoping I can free up some space, their resolution is pretty big so I decided to re encode them with ffmpeg to a smaller resolution, I am doing every thing manually, first I check using mediainfo test5.mkv the resolution

  ...
  
  Width                                    : 1 280 pixels
  
  ...

  if the width is greater than 720 pixels I issue the following command :

  ffmpeg -i 'test5.mkv' -vf scale=720:-2 -acodec copy -vcodec libx264 -scodec copy -threads 12 -crf 28 -x264-params keyint=240:min-keyint=20 -preset:v slow '[Encoded] test5.mkv'

  then after that I delete the original video if the output has smaller size than the original

  I am hoping there is a script that can automate this, like I will run on a directory then, it will look for all .mkv to subdirectories recursively to perform this checks and actions. How to do this ?

  Also, I am worried that it could fail if I reach automation, since there are special characters in the video’s name of some like single quotes, double quotes, or `, so I will it can be escaped properly.

  Thanks !

  After some google I ended up with the following snippet, I am worried if this is enough, but I’m afraid to run it since I am not sure if it would damage my unix

  #!/bin/sh
  
  
  
  for file in *.{mkv}; do
  
  target="[720p]-${file%.*}.mkv"
  
  [[ -f "$target" ]] && { echo "skipping $file - $target exists" ; continue; }
  
  
  
  
  
  eval $(ffprobe -v error -of flat=s=_ -select_streams v:0 -show_entries stream=height,width "$file")
  
  size=${streams_stream_0_width}x${streams_stream_0_height}
  
  if [ "$streams_stream_0_width" -ge 720 ]; then
  
  echo ffmpeg -i "$file" -vf scale=720:-2 -acodec copy -vcodec libx264 -scodec copy -threads 12 -crf 28 -x264-params keyint=240:min-keyint=20 -preset:v slow "$target"
  
  
  
  fi
  
  done

  can somebody please tell me if my snippet should work ?

  UPDATE

  as it turns out if [ "$streams_stream_0_width" -ge 720 ]; then fails because the width is not integer ? line 10: [: : integer expression expected I am not sure why it is not integer, how can I make it integer ?