Recherche avancée

Sur d’autres sites (6443)

• avcodec/ppc/fdctdsp : POWER LE support in ff_fdct_altivec() delete macros VEC_FMERGEH...

  27 avril 2015, par Rong Yan

  avcodec/ppc/fdctdsp : POWER LE support in ff_fdct_altivec() delete macros VEC_FMERGEH() VEC_FMERGEL(), they where wrong
  GCC tool had a bug of PPC intrinsic interpret, which has been fixed in GCC 4.9.1. This bug lead to
  
  errors in two of our previous patches. We found this when we update our GCC tools to 4.9.1 and by
  
  reading the related info on GCC website. We fix our previous error in two separate commits
  Signed-off-by : Michael Niedermayer <michaelni@gmx.at>
  

  • [DH] libavcodec/ppc/fdctdsp.c

• Delete the alpha channel from a video with ffmepg

  13 avril 2017, par virtualsets

  I will like remove the alpha channel of a mov file and create a new video, I prefer a copy version not transcodification.

  It is posible ? Thank you

• 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 ?