Recherche avancée

Sur d’autres sites (4947)

• C# app - running FFMpeg from the command line is not working

  11 avril 2017, par Dan Kahn

  I’m trying to run FFMpeg from the Command Line in C#. Previously I was running it from "CMD.exe" and it was working, but that requires a local installation of ffmpeg with configuring my System environmental variables. So I wanted to run it directly from "ffmpeg.exe". I’m using the following code (all the paths are correct), and nothing happens :

  string programToRun = "C:\\Users\\dkahn\\Documents\\PlaybackTool\\PlaybackTool\\Desktop\\Source\\Player\\Player\\ffmpeg\\ffmpeg.exe";
  
  
  
  string directoryName = "C:\\Users\\dkahn\\Documents\\PlaybackTool\\PlaybackTool\\Desktop\\Source\\Player\\test\\test1-1.mp4";
  
  
  
  string command = "@ffmpeg -i test1-1.mp4 -r 1  -s 180x101 test1-1\\output_%04d.png";
  
  
  
  Process cmd = new Process();
  
  cmd.StartInfo.FileName = programToRun;
  
  cmd.StartInfo.RedirectStandardInput = true;
  
  cmd.StartInfo.RedirectStandardOutput = true;
  
  cmd.StartInfo.CreateNoWindow = true;
  
  cmd.StartInfo.UseShellExecute = false;
  
  cmd.StartInfo.WorkingDirectory = directoryName;
  
  cmd.Start();
  
   cmd.StandardInput.WriteLine(command);
  
  cmd.StandardInput.Flush();
  
  cmd.StandardInput.Close();
  
  cmd.WaitForExit();

  Does anybody have any insight ?

• FFMPEG, itsoffset with overlay command

  9 janvier 2014, par G.T.

  I managed to overlay two videos one by another with the overlay command and use a nullsrc command to play both video till both of them ended with the following command :

  ./ffmpeg -i first.MOV -i second.MOV -filter_complex "nullsrc=size=1280x400:duration=30[bg];[0]scale=640:-1,pad=1280:400[first];[bg][first]overlay=0:0[base];[1]scale=640:-1[second];[base][second]overlay=640:0" output.mp4

  Now what I wanted to do is to delay one of the overlay till the other one finishes. For this as far as I know the command is itsoffset, so I modified to use this :

  ./ffmpeg -i first.MOV -itsoffset 5 -i second.MOV -filter_complex "nullsrc=size=1280x400:duration=30[bg];[0]scale=640:-1,pad=1280:400[first];[bg][first]overlay=0:0[base];[1]scale=640:-1[second];[base][second]overlay=640:0" output.mp4

  Now my only problem with this is that I want to show the first frame of the delayed video till it starts... And even though somewhere I read that this should do it, it won't. It leaves it blank till the input starts.

  Any idea how could I add the first frame of second video till the itsoffset starts the video ?

• Wave Goodbye ; What About VP8/WebM ?

  7 août 2010, par Multimedia Mike — Multimedia PressWatch

  Some big news in the geek community this past week came in the form of Google’s announcement that it would no longer be caring about its vaunted Wave technology. I was mildly heartbroken by this since I had honestly wanted to try Google Wave. Then I remembered why I never got a chance to try it : they made it an exclusive club at the beginning. I really did try to glean some utility out of the concept by reading documentation and watching videos and I had some ideas about how I might apply it. Then again, I try to think of a use for nearly any technology that crosses my path.

  It still struck me as odd : Why would Google claim that no one was interested in their platform when they wouldn’t give anyone a chance to try it out ? A little digging reveals that Google did open it for general use back around May 18. That date sounds familiar... oh yeah, VP8 was open sourced right around the same time. Maybe that’s why I don’t remember hearing anything about Wave at the time.

  But now I’m wondering about VP8 and WebM. How long do you think it might be before Google loses interest in these initiatives as well and reassigns their engineering resources ? Fortunately, if they did do that, the technology would live on thanks to the efforts of FFmpeg developers. A multimedia format has a far more clear-cut use case than Google Wave.