Recherche avancée

Sur d’autres sites (8678)

• OpenCV video writing to named pipe

  21 janvier 2012, par user28667

  I'm trying to send videos created with OpenCV in real-time to user though Apache (user downloads video from a website). I don't need streaming video. I'm just trying to transfer whole video file. My OpenCV program writes video to a named pipe (created with mkfifo) and PHP scrpt reads from it and outputs to user.

  The problem is that pipe-transfered videos doesn't open in Windows. They're shorter exactly at 7072 bytes (checked with different videos). They are not just truncated. The first difference between videos appeared in 5-th byte. And there is no mistake in PHP script. I've checked it using :

  cat fifo.avi > output.avi

  The result was the same. How to make OpenCV write videos to pipes just as to normal files ? Why this happens ? Or is there another way to send videos in real-time to user ?

  P. S. Thanks and sorry for bad English
  P. P. S. I'm creating CvVideoWriter with this code if it matters :

  cvCreateVideoWriter("fifo.avi",CV_FOURCC('M','J','P','G'),25,cvSize(blah blah blah),1)

• ffmpeg in a bash pipe

  5 mai 2014, par Martin Wang

  I have a rmvb file path list, and want to convert this files to mp4 files. So I hope to use bash pipeline to handle it. The code is

  Convert() {
  
      ffmpeg -i "$1" -vcodec mpeg4 -sameq -acodec aac -strict experimental "$1.mp4"
  
  }
  
  
  
  Convert_loop(){
  
      while read line; do
  
         Convert $line
  
      done
  
  }
  
  
  
  cat list.txt | Convert_loop

  However, it only handle the first file and the pipe exits.

  So, does ffmpeg affect the bash pipe ?

• How to use pipe in ffmpeg within c#

  21 avril 2016, par Andrew Simpson

  I have 100 jpegs.

  I use ffmpeg to encode to a video file which is written to a hard drive.

  Is there a way to pipe it directly to a byte/stream ?

  I am using C# and I am using the process class to initate ffmpeg.

  Thanks