big delay in 1st minute. it get bigger every minute? the time on camera screen falling behing compared to computer time.

[blackholeearth]

Delay between time on the wallclock vs time on captured frame gets bigger amd bigger each passing second.

can i do frame skip?

or just take 1 photo?

---

Edit: SOLVED go th the end

[tinohager]

sorry I don't think your request is a problem for the library. I would try changing the streaming resolution of the camera.

[blackholeearth]

ipcam encoding is: 704x576p, h265 , 10 fps , BRC_CBR , 512kbps , i interval 20 (keyframe, i think?)

İ wanted to do face detection with captured photo. İf i go lower than this it's unusable.

[tinohager]

then you have to separate your logic and put the images in a queue first and do the processing in another thread

[blackholeearth]

ipcam is: 704x576p, stream is h265 , 10 fps , BRC_CBR , 512kbps bitsream , i interval 20,(i think this is keyframe)

i did seperate it to different thread via taskRun,

i am cool with constant delay lets say 5 seconds. thats acceptable for me. but that 5 second delay becomes. 40 seconds after the 2 minutes. gets bigger.

here code if you want to see:

CancellationTokenSource last_ct;

  private void bt_rtspSTART_Click(object sender, EventArgs e)
        {
            last_ct?.Cancel();

            var rtsp_url = @"rtsp://admin:pass@192.168.1.51:554/cam/realmonitor?channel=1&subtype=1";
            var inputSource = new StreamInputSource(rtsp_url);
            var cancellationTS = new CancellationTokenSource();
            last_ct = cancellationTS;

            var client = new VideoStreamClient();
            client.NewImageReceived += NewImageReceived;
            var task = client.StartFrameReaderAsync(inputSource, OutputImageFormat.Bmp, cancellationTokenSource.Token);
            //client.NewImageReceived -= NewImageReceived;

        }

        /// <summary>
        /// to show in picturebox.
        /// </summary>
        public static Bitmap ByteToImage(byte[] blob)
        {
            MemoryStream mStream = new MemoryStream();
            byte[] pData = blob;
            mStream.Write(pData, 0, Convert.ToInt32(pData.Length));
            Bitmap bm = new Bitmap(mStream, false);
            mStream.Dispose();
            return bm;
        }

        DateTime lastCopied = DateTime.Now;
        byte[] last_imageData = null;
        private void NewImageReceived(byte[] imageData)
        {
            if (DateTime.Now.Subtract(lastCopied).TotalMilliseconds < 2_000)  // taking photo every to 2second.
                return;

            lastCopied = DateTime.Now;
            last_imageData = imageData;
            Task.Run(()=> {
                if (last_imageData == null)
                    return;

                var bitmapx = ByteToImage(last_imageData);  //90ms on my computer ,debug. 
                this.Invoke(new Action(() => {
                    pbx_vidframe.Image = bitmapx;
                    tbx_tarihsaat.Text = $"DataReceived_TarihSaat: {lastCopied}";
                }));

            });
            //File.WriteAllBytes($@"{DateTime.Now}.bmp", imageData);
        }

cant we add custom ffmpeg parameters to fix that.

current default way its unsuable. please help.

---

please keep the issue open. its not fixed. maybe someone sees and send a pr.

[tinohager]

It's definitely not a problem with the library it's a problem with the implementation of it. The way the code from your example processes the data cannot work properly. This GitHub project is also not a free support that fixes your code I hope you can understand that.

However, I can offer you professional support with your problem. I have already given you the correct solution in my previous answer.

[blackholeearth]

the code is copied from readme page ??

that means the same problem happens with the basic example on readme page. when you are writing frame on a disk.??

[tinohager]

Thank you for the nice conversation please look for help on stackoverflow or in another forum

[blackholeearth]

tested the test.console app on this repo. same thing happens there. 👀👀

so the problem is not my code.

thanks for ur concern . can close for real this time.

---

Edit: found some message on console app.

Framerate is not specified . 25fps will be used.

İ know ipcam fps is 10. So i appended " -r 10 " to customstreamsource.

After running code for 60 seconds. delay is 20 sec now.

Halfway there..✨✨

---

Also At the console app output, i see fps Value is changing between 9.111 - 9.999

This will definitely be solved by finding right flags for ffmpeg .

[blackholeearth]

early observations: tested it for 2 minutes. delay is 2 sec. it looks constant. 👍 tested it for 30 minutes. delay is 2 to 3 sec. it looks constant. 👍

code

var rtsp_url = @"rtsp://admin:pass@192.168.1.12:554/cam/realmonitor?channel=1&subtype=1";
var inputSource = new CustomInputSource($"-flags low_delay  -rtsp_transport tcp -i {rtsp_url}  -r 4 ");

solution:
set fps in c# code to a lower value than actual ipcam stream

solution - step by step:

1) download and run the test.console app. 2) see if there is fps not detected meesage`in console app: Framerate is not specified . 25fps will be used.

• wait little bit, you will see avg fps 3) learn your fps of that stream.
  • you have previosly saw it in the console app . (in my case its going between 9.1-- 9.9 )
  • either open the url with potplayer or vlc
    • ( to play x265 stream , might need to install lav filter from github) 4) set fps in c# code to a lower value than actual ipcam stream.
  • use the code above i give (in my case i set it to 4)