Recherche avancée

Sur d’autres sites (7604)

• hwcontext_qsv : do not fail when download/upload VPP session creation fails

  10 août 2016, par Anton Khirnov

  hwcontext_qsv : do not fail when download/upload VPP session creation fails
  Certain pixel formats (e.g. P8) might not be supported for
  
  download/upload through VPP operations, but can still be used otherwise.
  Signed-off-by : Maxym Dmytrychenko <maxym.dmytrychenko@intel.com>
  

  • [DBH] libavutil/hwcontext_qsv.c

• How to calculate the "Range" header for mp4 file to play/download a part of it ? [youtube-dl]

  5 décembre 2016, par supersan

  I’m using youtube-dl to download videos from YouTube. Unfortunately, sometimes I just need to download a part of the video like 10 seconds of a 3 hour video and here is how I see I can do it.

  Step 1 : Get the URL of the mp4 file from youtube-dl.

  youtube-dl -g -f "[ext=mp4]" https://www.youtube.com/watch?v=qOZ1u9VpoMk

  This returns $url : the full URL of mp4 file on server.

  Step 2 : Download part of the video using curl

  curl -r $startBytes-$endBytes $url

  But how to calculate $startBytes and $endBytes. What is the formula for that ?

  P.S I was thinking could be something as simple but this isn’t it..

  $startBytes = (total_size_of_video / total_length_of_video_secs) * start_seconds

  P.P.S. When I play the mp4 video in Chrome and use the scrub bar to jump around in the video, Chrome too send the Range header to the same URL (as I can see in fiddler)

• Bash : bash script to download trimmed mp3 from youtube url

  23 février 2017, par Bhishan Poudel

  I would like to download the initially x seconds trimmed mp3 from a video url of youtube.
  I found that youtube-dl can download the video from youtube to local machine. But, when I looked at the man pages of youtube-dl, I could not find any trim options.

  So I tried to use the ffmpeg to trim downloaded mp3 file.
  Instead of doing this is two steps, I like to write one bash script which does the same thing.
  My attempt is given below.

  However, I was stuck at one place :
  "HOW TO GET THE VARIABLE NAME OF OUTPUT MP3 FILE FROM YOUTUBE-DL ?"
  The script is given below :

  # trim initial x seconds of mp3 file
  
  # e.g. mytrim https://www.youtube.com/watch?v=dD5RgCf1hrI 30
  
  function mytrim() {
  
      youtube-dl --extract-audio --embed-thumbnail --audio-format mp3 -o "%(title)s.%(ext)s" $1
  
      ffmpeg -ss $2 -i $OUTPUT_MP3 -acodec copy -y temp.mp3
  
      mv temp.mp3 $OUTPUT_MP3
  
      }

  How to get the variable value $OUTPUT_MP3 ?
  echo "%(title)s.%(ext)s" gives the verbatim output, does not give the output filename.

  How could we make the script work ?

  The help will be appreciated.