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• FFmpeg - Record video feed from camera and store each frame timestamp

  21 mars 2023, par Buzz

  I've searched far and wide here on SO and I've found lots of similar question, but most of them regarding either single snapshot recording, offline video processing or drawing timstamp on a frame.

  


  I'm quite new to ffmpeg, so sorry if the question is very trivial.

  


  I'd need to record a video feed from a camera and to store (into the same video file, if any, or in a separate textual file) each frame timestamp (absolute, not relative)

  


  I've noticed that many have used -frame_pts, but, though pertinent, I'm not sure how to integrate it for the issue above.

  


• Using ffmpeg.exe making the computer slow in task manager it takes over 1GB of memory how can i fix it ?

  29 mai 2013, par Revuen Ben Dror

  In mt Form1 i have this code :

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

  ffmp is a variable of my class : Ffmpeg
  In this class i add frames to a pipe and create an avi file.

  using System;
  
  using System.Collections.Generic;
  
  using System.Linq;
  
  using System.Text;
  
  using System.Threading.Tasks;
  
  using System.Drawing;
  
  using System.IO.Pipes;
  
  using System.Runtime.InteropServices;
  
  using System.Diagnostics;
  
  
  
  namespace ScreenVideoRecorder
  
  {
  
      class Ffmpeg
  
      {
  
          NamedPipeServerStream p;
  
          String pipename = "mytestpipe";
  
          byte[] b;
  
          System.Diagnostics.Process process;
  
  
  
          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.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;
  
  
  
              p.WaitForConnection();
  
          }
  
  
  
          public void PushFrame(Bitmap bmp)
  
          {
  
  
  
              int length;
  
              // Lock the bitmap's bits.
  
              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];
  
  
  
              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);
  
  
  
          public void Close()
  
          {
  
              p.Close();
  
          }
  
      }
  
  }

  The problem is when i'm running my application in this from my visual studio 2012 pro and click the button it's openning a console window and start the processing .

  I tracked over it through the task manager on ffmpeg.exe and saw that it started from 996mb and very quick jumped ot 1040mb memory usage. The cpu usage was only 16%

  Once i close ended this task the ffmpeg.exe everything was back to move smooth.
  When it's working and i tried to drag my Form around the screen for example it was moving slow and also with some stuttering .

  Closed the ffmpeg.exe and i could drag the Form around smooth and quick like in regular way as it should be.

  I tried to google for it and found some others with the same problem i think but i'm not sure where is the problem and how to fix it.

  I'm not sure what version of ffmpeg.exe i have i'm using now but i read in some places that it's not working better with new versions but maybe i mistake here .

  My windows is 8 with 6gb of ram .

• Android-Player-SDK's overview of available Player Frameworks

  8 janvier 2015, par user1767754

  I am completely lost with the possibilities of creating Video-Applications for Android. There is natively the MediaPlayer from Android, or the VideoView which is more convenient but at the same time, there are so many different Video-Player-SDK’s around, that someone cannot see what the benefits are between those Players and which one to use.

  For example, what are the benefits of Vitamino over native Player ?

  Let’s say :
  1) Change Appearing of Player

  2) Add Additional Buttons [E-Mail Video-Link, etc.]

  3) Add Additional Functionality [Overlay text, Drawing]

  4) Get Streaming over a Network-Protocoll

  I hope we can build up here an overview page of available Frameworks and Developer Experiences.