Recherche avancée

Sur d’autres sites (5663)

• ffmpeg's strange behaviour-Conversion started when I close my application

  16 décembre 2013, par m.qayyum

  I'm using ffmpeg in my application to rotate video, but problem is that when I start conversion ffmpeg only shows it's version information and not start the actual conversion, but when I close my application ffmpeg process remains in Running Processes in Taskbar and start to convert the file.

  ffmpeg output
  

  Here is my code, please tell me where i'm doing it wrong.

  void ConvertVideo(object[] arr) {
  
  
  
      string Argument = (string)arr[0];
  
      string OutputFolder = (string)arr[1];
  
      string ConvertedFile = (string)arr[2];
  
  
  
  
  
      UpdateStatus("Converting! Please wait...");
  
      ffmpeg = new Process();
  
      ffmpeg.StartInfo.WindowStyle = ProcessWindowStyle.Hidden;
  
      ffmpeg.StartInfo.FileName = "ffmpeg.exe";
  
      ffmpeg.StartInfo.UseShellExecute = false;
  
      ffmpeg.StartInfo.RedirectStandardError = true;
  
      ffmpeg.StartInfo.RedirectStandardOutput = true;
  
      ffmpeg.StartInfo.CreateNoWindow = true;
  
      ffmpeg.StartInfo.Arguments = Argument;
  
      ffmpeg.Start();
  
      myStreamReader = ffmpeg.StandardError;
  
      outputLine = myStreamReader.ReadLine();
  
      UpdateRTB(outputLine);//Write line to ritchtextbox
  
      do
  
      {
  
          if (outputLine.Contains("muxing overhead"))
  
          {
  
              UpdateStatus("Muxing video");
  
          }
  
  
  
          if (outputLine.StartsWith("frame"))
  
          {
  
              UpdateStatus("Converting video");
  
          }
  
      }
  
      while (!(ffmpeg.HasExited & (string.Compare(outputLine, "") == 0 | outputLine == null)));
  
      ffmpeg.Close();
  
      myStreamReader.Close();
  
      UpdateStatus("Convertion completed successfully");
  
  }

• Comparing PSNR of two videos, possibly with ffmpeg ?

  22 décembre 2016, par UnixNerd

  I would like to compare a large number of videos to a good reference video in order to find videos with poor quality. I want to do this in a batch mode by calling a command line utility, I’m already using ffmpeg in this manner to grab video frames.

  ffmpg will give me a PSNR value to compare the input and output videos if I transcode a video. I was under the impression I could use something like this to compare two separate videos but can’t find a way to do it.

  Would I be better grabbing a single frame from each video and comparing those somehow ? PSNR may not be the best option for me ?

  I’m not looking for minor differences in quality but for major differences such a sync problems or large amounts of snow.

  Any suggestions ? Thanks in advance :-)

• Revision 5215b83aea : Simplifying and inlining k_cvtlo_epi16 and k_cvthi_epi16 Simplify the k_cvtlo_e

  3 octobre 2013, par A.Mahfoodh

  Changed Paths :
   Modify /vp9/encoder/x86/vp9_dct32x32_sse2.c

  
  
  Simplifying and inlining k_cvtlo_epi16 and k_cvthi_epi16

  Simplify the k_cvtlo_epi16 and k_cvthi_epi16 to only two
  instructions. Then inlined them.

  quoting from intel MMX_App_Compute_16bit_Vector.pdf‎
  "The PMADDWD instruction multiplies four
  pairs of 16-bit numbers and produces partial sums of the results
  and can do so once per clock (with a three-clock latency)."
  so I am assuming that there will be three clock overhead after the
  last _mm_madd_pi16 command.
  Even with the overhead the number of clocks in general should be
  smaller. I am not sure though becasue I could not find information
  about number of clocks required for instructions in k_cvtlo_epi16
  and k_cvthi_epi16. I will run a test and compare the execution time.

  Change-Id : Ieda4aa338f69ad3dd196ac6e7892da3cf1b47ea7