• DepthAI

  • Unstable connection / connectivity issues

I'm reading through the code.

https://github.com/luxonis/depthai-core/blob/main/src/device/Device.cpp

https://github.com/luxonis/depthai-core/blob/main/src/device/DeviceBase.cpp

https://github.com/luxonis/depthai-core/blob/main/include/depthai/device/Device.hpp

Adding to the discussion, what I'm seeing is that both dai::Device and dai::DeviceBase constructors always call startPipeline(), which is an expensive blocking operation. I don't mean to be rude, but this is a crime against object orientation.

Here are some screenshots. The code executing is as follows.

std::vector<std::uint8_t> PSCore::Test1()

{

using namespace std;

dai::Device \*dptr = nullptr;

try

{    

    // Create pipeline

    dai::Pipeline pipeline;

    // Define source and output

    auto camRgb = pipeline.create<dai::node::ColorCamera>();

    auto xoutRgb = pipeline.create<dai::node::XLinkOut>();

    xoutRgb->setStreamName("rgb");

    xoutRgb->input.setBlocking(false);

    xoutRgb->input.setQueueSize(1);

    // Properties

    camRgb->setBoardSocket(dai::CameraBoardSocket::RGB);

    camRgb->setResolution(dai::ColorCameraProperties::SensorResolution::THE_1080_P);

    camRgb->setInterleaved(false);

    camRgb->setColorOrder(dai::ColorCameraProperties::ColorOrder::BGR);

    //camRgb->setPreviewSize(300, 300);

    //camRgb->setVideoSize(4056, 3040);

    camRgb->setVideoSize(1920, 1080);

    // Linking

    //camRgb->preview.link(xoutRgb->input);

    camRgb->video.link(xoutRgb->input);

    // Connect to device and start pipeline

    auto deviceInfo = dai::DeviceInfo("192.168.8.116");

    auto device = dai::Device(pipeline, deviceInfo);

    dptr = &device;

    cout << "Connected cameras: " << device.getConnectedCameraFeatures() << endl;

    // Print USB speed

    // device already closed or disconnected exception

    //cout << "Usb speed: " << device.getUsbSpeed() << endl;

    // Bootloader version

    if(device.getBootloaderVersion()) {

        cout << "Bootloader version: " << device.getBootloaderVersion()->toString() << endl;

    }

    // Device name

    cout << "Device name: " << device.getDeviceName() << endl;

    // Output queue will be used to get the rgb frames from the output defined above

    //auto qRgb = device.getOutputQueue("rgb", 4, false);

    auto qRgb = device.getOutputQueue("rgb");

    while(true) 

    {

        auto inRgb = qRgb->get<dai::ImgFrame>();

        auto type = inRgb->getType();

        auto data = inRgb->getData();

        device.close();

        return data;

    }

}

catch(const std::exception &ex)

{

    cout << ex.what();

    int stophere = 7;

}

catch(...)

{

    int stophere = 7;

}

//cleanup

if(dptr != nullptr)

{

    dptr->close();

    //delete dptr;

}

return {};

}

These screenshots are successive runs.

run #1, exception thrown

run #2, successful

run #3, run#4, run#5 - all same as run #1

run #6, successful

run #7

It now appears that the device itself has crashed. I've run dozens of times and always same as run#7 results. How can the device be crashing???? Touching the device it is cold to the touch, which so far is the best method I've found to check if the device is online or not.

Is this normal behavior, for the firmware on the device to crash? What is the best way to tell if the device is running or not? Is there a status light or something I could turn on?

After power cycling the PoE/device, I started getting successful runs again. Then this. So if you look back at the code, I got through the line auto device = dai::Device(pipeline, deviceInfo);, but then an exception was thrown in midst of device.getConnectedCameraFeatures(). LOL. When I say random errors this is what I mean. This is extremely simple code, it's quite literally your sample code. Am I having a normal experience here? Is there something physically wrong with this camera?

Oop, here we go again. This time I made it to the line cout << "Device name: " << device.getDeviceName() << endl; where it threw on device.getDeviceName().

🫠☠️🫠☠️🫠☠️

I updated to latest repo, v2.21.2, and don't really see much of a difference. This is it?

  • erik replied to this.

    Hi jt512 ,

    Please also try the latest develop version of depthai library - relevant github issue here.

    Thanks, Erik

      The branches main, v2.21.2, and develop are all at the same commit…

      I see, it was just released 2 hours ago. The main changes are in the firmware, see commit here.

        I am also experiencing deadlocks on dai::Device::close() quite frequently. Referring to the code above, after getting a single frame, I call device.close(), break out of the loop and return the single frame. Deadlock on device.close();

        erik You're saying there is a firmware update paired with this? This is new to me so I need some explanation to understand what this means. Where are the side binaries kept?

        • erik replied to this.

            Hi jt512 ,

            Best to report the deadlock issue on depthai-core with minimal repro example. For firmware - for C++ I believe it gets downloaded at build time from our servers, while for python it's bundled together into a wheel. Firmware is closed source (our core IP).

            Thanks, Erik

              I'm gonna send an email.

              FYI, I can confirm the 2.21.2 update does nothing. Same exact sporadic connectivity issues.

              • erik replied to this.

                Hi jt512 ,

                Please open an issue on depthai-core with specifications of the sporadic connectivity issues so firmware engineers can repro/debug easily.

                Thanks, Erik