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• Why when recording video using ffmpeg command line when playing the video it's running very fast ?

  31 mai 2013, par Revuen Ben Dror

  This is my code in Form1 :

  private void StartRecording_Click(object sender, EventArgs e)
  
          {
  
  
  
              ffmp.Start("test.avi", 25);
  
              timer1.Enabled = true;
  
          }

  The timer tick event :

  private void timer1_Tick(object sender, EventArgs e)
  
          {
  
              using (bitmap = (Bitmap)ScreenCapture.CaptureScreen(true))//(Bitmap)ScreenCapture.CaptureScreen(true))
  
              {
  
              ffmp.PushFrame(bitmap);
  
              }  
  
  
  
          }

  Then the code in the ffmpeg class i did :

  namespace ScreenVideoRecorder
  
  {
  
      class Ffmpeg
  
      {
  
          NamedPipeServerStream p;
  
          String pipename = "mytestpipe";
  
          byte[] b;
  
          //int i, j;
  
          System.Diagnostics.Process process;
  
          //IAsyncResult ar;
  
  
  
          public Ffmpeg()
  
          {
  
  
  
          }
  
  
  
          public void Start(string FileName, int BitmapRate)
  
          {
  
              p = new NamedPipeServerStream(pipename, PipeDirection.Out, 1, PipeTransmissionMode.Byte);
  
              b = new byte[1920 * 1080 * 3]; // some buffer for the r g and b of pixels of an image of size 720p 
  
              process = new System.Diagnostics.Process();
  
              //process.StartInfo.WindowStyle = ProcessWindowStyle.Hidden;
  
              process.StartInfo.FileName = @"D:\pipetest\pipetest\ffmpegx86\ffmpeg.exe";
  
              process.EnableRaisingEvents = false;
  
              process.StartInfo.WorkingDirectory = @"D:\pipetest\pipetest\ffmpegx86";
  
              process.StartInfo.Arguments = @"-f rawvideo -pix_fmt bgr0 -video_size 1920x1080 -i \\.\pipe\mytestpipe -map 0 -c:v libx264 -r " + BitmapRate + " " + FileName;
  
              process.Start();
  
              process.StartInfo.UseShellExecute = false;
  
              process.StartInfo.CreateNoWindow = false;
  
              //ar = p.BeginWaitForConnection(EndWait,null);
  
              p.WaitForConnection();
  
          }
  
  
  
          public void PushFrame(Bitmap bmp)
  
          {
  
  
  
              int length;
  
              // Lock the bitmap's bits.
  
              //bmp = new Bitmap(1920, 1080);
  
              Rectangle rect = new Rectangle(0, 0, bmp.Width, bmp.Height);
  
              //Rectangle rect = new Rectangle(0, 0, 1280, 720);
  
              System.Drawing.Imaging.BitmapData bmpData =
  
                  bmp.LockBits(rect, System.Drawing.Imaging.ImageLockMode.ReadOnly,
  
                  bmp.PixelFormat);
  
  
  
              int absStride = Math.Abs(bmpData.Stride);
  
              // Get the address of the first line.
  
              IntPtr ptr = bmpData.Scan0;
  
  
  
              // Declare an array to hold the bytes of the bitmap.
  
              //length = 3 * bmp.Width * bmp.Height;
  
              length = absStride * bmpData.Height;
  
              byte[] rgbValues = new byte[length];
  
  
  
              //Marshal.Copy(ptr, rgbValues, 0, length);
  
              int j = bmp.Height - 1;
  
              for (int i = 0; i < bmp.Height; i++)
  
              {
  
                  IntPtr pointer = new IntPtr(bmpData.Scan0.ToInt32() + (bmpData.Stride * j));
  
                  System.Runtime.InteropServices.Marshal.Copy(pointer, rgbValues, absStride * (bmp.Height - i - 1), absStride);
  
                  j--;
  
              }
  
  
  
              p.Write(rgbValues, 0, length);
  
  
  
              bmp.UnlockBits(bmpData);

  The ffmpeg command line is :

  process.StartInfo.Arguments = @"-f rawvideo -pix_fmt bgr0 -video_size 1920x1080 -i \\.\pipe\mytestpipe -map 0 -c:v libx264 -r " + BitmapRate + " " + FileName;

  And i checked with a breakpoint and saw that the variable BitmapRate is 25 .
  And the timer interval is 40 .

  So it should fit for 25 frames per seconds.
  But when i'm running the video file using MPC Media Player Class everything in the video is running very fast. I mean the video is 2,326KB size the video Length is 16 seconds .

  And everything in the video seems to mvoe very fast if i opend a new window or dragged a window somewhere in the screen i see it moving very fast and as it i moved and did everything in real .

  I see on the video file details that : length 16 seconds. 1920x1080 and 25 frames per second.

  So where is the problem ? i can't figure out.

• hevc : remove a redundant line

  15 novembre 2014, par Anton Khirnov

  hevc : remove a redundant line
  pred_mode is overwritten a few lines immediately below.
  

  • [DH] libavcodec/hevc.c

• hevc : remove a redundant line

  15 novembre 2014, par Anton Khirnov

  hevc : remove a redundant line
  pred_mode is overwritten a few lines immediately below.
  

  • [DBH] libavcodec/hevc.c