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• FFMpeg extremely slow - when called from asp.net

  9 juillet 2013, par Daveo

  I have a C# .NET website hosted on WIN2003 IIS6. This calls a .exe I have made (also in .net) using System.Diagnostics.Process which in turn calls a .bat script to convert a video into web formats (h264/MP4 and WEBM)

  ::Make MP4 ffmpeg.exe -i "%1" -y -vcodec libx264 -pix_fmt yuv420p
  -vprofile high -b:v 600k -maxrate 600k -bufsize 1200k -s 480x320 -threads 0 -acodec libvo_aacenc -b:a 128k "%2\video.mp4"

  ::Make WemM (VP8 / Vorbis) ffmpeg.exe -i "%1" -y -vcodec libvpx -b:v
  600k -maxrate 600k -bufsize 1200k -s 480x320 -threads 3 -acodec
  libvorbis -f webm "%2\video.webm"

  When I test it it seems to work fine a 70Mb input file will take about 4 minute to convert to mp4 then 6 minutes to convert to webm. Which is fine ! However whenever the customer test it the ffmpeg encoding taking HOURS (5 - 10 hours for one video) .

  When I look at windows task manager it shows a 2-3 instances of ffmpeg using cpu. When I refresh the output folder I can see the file increasing at 1Kb / second very slow. Why could this be happening ?

  my .net code

  private  bool Convert(string inputFile, string outputFolder)
  
          {
  
              string exePath = ConfigurationManager.AppSettings["BatchFile"];
  
              ProcessStartInfo startInfo = new ProcessStartInfo(exePath);
  
  
  
              startInfo.Arguments = string.Format("{0} {1}", inputFile, outputFolder);
  
              startInfo.FileName = exePath;
  
              startInfo.UseShellExecute = true;
  
              startInfo.CreateNoWindow = true;
  
  
  
  
  
              using (Process process = new Process())
  
              {
  
                  process.StartInfo = startInfo;
  
  
  
                  try
  
                  {
  
                      bool success;
  
                      int waitTimeInMinutes = int.Parse(ConfigurationManager.AppSettings["VideoConversionTimeout"]);
  
                      process.Start();
  
                      process.WaitForExit(1000 * 60 * waitTimeInMinutes); // Give up after Xmins 
  
  
  
                      success = (process.ExitCode == 0);
  
  
  
                      return success;
  
  
  
                  }
  
                  catch (Exception e)
  
                  {
  
                      log.ErrorException("Main exception", e);
  
                      return false;
  
                  }
  
              }
  
          }

• FFmpeg performance on android devices

  14 juin 2017, par LemanRass

  I’m trying to make an app for android via Unity3D game engine which will basically
  be a video player.
  I decide to use FFmpeg library which i linked to my C++ plugin using Android NDK.
  I’m trying to play at least HD video and i stuck on performance problem.
  Retrieving each frame of HD resolution takes near than 40 milliseconds of time. 1000 / 40 = 25 fps which is already not good enough because i did n`t even wrote audio handling yet. But how about full hd videos ? Another video players on my device somehow playing full hd videos but i don’t even know how they do.

• Improve ffmpeg CPU usage by compromising quality

  29 septembre 2016, par Hardik Juneja

  I am using FFMpeg for screen capturing.
  I am looking for a screen capturing tool that will run on 1000 of VMs (windows and mac).The VMs have limited CPU (1 core) and 2GB ram and No GPU.

  Currently I invoke ffmpeg with

  ffmpeg  -y -framerate 8 -f dshow -f gdigrab -i "desktop"  -c:v libx264  -crf 0 -preset ultrafast -threads 0 temp.mkv

  I am using gdigrab to capture screen ? Is there any better options that might reduce cpu usage ? or changing the encoder or format ?

  I am aiming for 4-5% reduction in CPU usage.

  Thanks in advance