AlanElkin

  • Sep 9, 2024
  • Joined Apr 4, 2024
  • 1 best answer
  • In Getting slow FPS for Still images

    Hi @AlanElkin
    Please redo the test with the updated bandwidth script. Pretty sure it was locking the transmission to 5Gbps (gen1) which caused them all to behave similarly.

    Thanks,
    Jaka

    • In Getting slow FPS for Still images

      Hi @AlanElkin ,
      Interesting! Does the USB C to C cable provide any better bandwidth / lower latency if you run the test scripts? My understanding was that it shouldn't change, as they\re both using the same USB3.1 interface.
      Thanks, Erik

      • In Getting slow FPS for Still images

        Hi @AlanElkin ,
        Could you try some other host computer as well? I'd suspect the USB hub/card in the computer itself.

        • In Getting slow FPS for Still images

          @AlanElkin still isn't meant for fast captures, you can use isp output for that, which should provide better latency/fps. But USB hubs do add additional overhead;

          • I get around 17fps when using OAK USB -> USB hub -> Mac
          • I get around 30fps when using OAK USB -> Mac directly
          • In Getting slow FPS for Still images

            Hi @AlanElkin
            Yeah, I get the same.
            Are you setting with dai.Device(pipeline, maxUsbSpeed=dai.UsbSpeed.SUPER_PLUS) as device:?

            The above script you have sent has SUPER_PLUS enabled, I'm just rechecking because removing this results in similar FPS to what you have.

            Thanks,
            Jaka

            • In Getting slow FPS for Still images

              Hi @AlanElkin
              Only thing I changed is the chunk size:

              Received 1 frames in 0:00:00.033700 --> Rate: 29.67 fps
Received 1 frames in 0:00:00.034360 --> Rate: 29.10 fps
Received 1 frames in 0:00:00.033957 --> Rate: 29.45 fps
Received 1 frames in 0:00:00.031237 --> Rate: 32.01 fps
Received 1 frames in 0:00:00.034367 --> Rate: 29.10 fps
Received 1 frames in 0:00:00.033948 --> Rate: 29.46 fps
Received 1 frames in 0:00:00.032999 --> Rate: 30.30 fps
Received 1 frames in 0:00:00.034044 --> Rate: 29.37 fps
Received 1 frames in 0:00:00.032406 --> Rate: 30.86 fps
Received 1 frames in 0:00:00.034284 --> Rate: 29.17 fps
Received 1 frames in 0:00:00.032633 --> Rate: 30.64 fps
Received 1 frames in 0:00:00.033902 --> Rate: 29.50 fps
Received 1 frames in 0:00:00.034529 --> Rate: 28.96 fps
Received 1 frames in 0:00:00.032338 --> Rate: 30.92 fps
Received 1 frames in 0:00:00.033070 --> Rate: 30.24 fps
Received 1 frames in 0:00:00.033563 --> Rate: 29.79 fps

              Are you using a POE device or a slow USB cable by any chance? luxonis/depthai-experimentsblob/master/random-scripts/oak_bandwidth_test.py

              Thanks,
              Jaka

              • In Getting slow FPS for Still images

                Hi @AlanElkin
                Adding pipeline.setXLinkChunkSize(0) should speed up the processing and Xlink transport.

                Thanks,
                Jaka