Consideration to use Basler a2A series

KAGRA uses acA640-120gm cameras as the GigE system. Cameras are controlled by pylon-camera-server developed in LIGO. When considering the use of a Basler cameras with pylon-camera-server also for TCam, a2A5328-4gmPRO was listed up as a candidate that satisfies the specification requirements. We then verified the compatibility between a2A5328-4gmPRO and pylon-camera-server.

Conclusion

There was no compatibility between a2A5328-4gmPRO as SDK/GenlCam 2.x and pylon-camera-server as SDK/GenlCam 1.x.
The best solution from the view point of human resources is to find another camera as SDK/GenlCam 1.x which satisfies the specification requirements.
It's possible to modify pylon-camera-server, but many changes and great efforts are required.
- Modifying pylon-camera-server to make compatibility with both 1.x and 2.x is not so fruitful because 3.x and 4.x already exist.
- So, the 2nd best solution may be to fork pylon-camera-server as pylon-camera-server2 which is compatible only with 2.x if a2A5328-4gmPRO is really used at the very limited places.

First trial

Config file was prepared as /kagra/camera/pylon-camera-config/K1-CAM-TEST0.ini. Different settings are only resolution (5328x4608 instead of 640x480) and frame rate (4fps instead of 25fps) as follows.
```
width=5328
height=4608
framerate_numerator=4
```
Camera server can be launched by following command.
```
> /kagra/camera/pylon-camera-service start TEST0
```

EPICS IOC was running but camera images cannot be received by camera_client because pylon-camera-server showed a following error.

Feb 18 15:42:55 k1cam2 systemd[750]: Started pylon-camera-server@K1-CAM-TEST0.service - Basler 2D GigE camera RTP H264 UDP server.
Feb 18 15:42:55 k1cam2 pylon-camera-server[2132807]: Obtained request pad src_0 for appsink branch.
Feb 18 15:42:55 k1cam2 pylon-camera-server[2132807]: Obtained request pad src_1 for udpsink branch.
Feb 18 15:42:55 k1cam2 pylon-camera-server[2132807]: Starting main loop.
Feb 18 15:42:55 k1cam2 pylon-camera-server[2132807]: cas warning: Configured TCP port was unavailable.
Feb 18 15:42:55 k1cam2 pylon-camera-server[2132807]: cas warning: Using dynamically assigned TCP port 38533,
Feb 18 15:42:55 k1cam2 pylon-camera-server[2132807]: cas warning: but now two or more servers share the same UDP port.
Feb 18 15:42:55 k1cam2 pylon-camera-server[2132807]: cas warning: Depending on your IP kernel this server may not be
Feb 18 15:42:55 k1cam2 pylon-camera-server[2132807]: cas warning: reachable with UDP unicast (a host's IP in EPICS_CA_ADDR_LIST)
Feb 18 15:42:55 k1cam2 pylon-camera-server[2132807]: The camera is connected.
Feb 18 15:42:55 k1cam2 pylon-camera-server[2132807]: Attaching camera.
Feb 18 15:42:56 k1cam2 pylon-camera-server[2132807]: Opening camera.
Feb 18 15:42:56 k1cam2 pylon-camera-server[2132807]: Device Model Name: a2A5328-4gmPRO
Feb 18 15:42:57 k1cam2 pylon-camera-server[2132807]: Parameter not found in CStringParameter::GetValue. (No node attached.)

Accessing camera device was succeeded, but camera property cannot be obtained at the beginning of the server launching.

Details

Differences that affect the use of pylon-camera-server

	acA640-120gm	a2A5328-4gmPRO
Maximum resolution	`659×494`	`5328×4608`
Maximum frame rate	`120`	`~4.8`
SDK/GenlCam version	`1.x`	`2.x`
Class members	`camera.GevCurrentIPAddress`	`device (*1)`
	`camera.DeviceID`	`camera.DeviceSerialNumber`
	`camera.AcquisitionFrameRateAbs`	`camera.AcquisitionFrameRate`
	`camera.ResultingFrameRateAbs`	`camera.ResultingFrameRate`
	`camera.ExposureTimeRaw`	`camera.ExposureTime`
	`camera.GainRaw`	`camera.Gain`

Some of different class members are used in the main infinite-loop as follows, so it's difficult to insert version check for each call of member class.

while (1) {
    ~
    ~
    if (epics_exposure_time_raw_set > 0) {
        g_print("Setting exposure time: %i\n", epics_exposure_time_raw_req);
        camera.ExposureTimeRaw.TrySetValue((int64_t) epics_exposure_time_raw_req, Pylon::IntegerValueCorrection_Nearest);
        exposure_time_raw_set = 0;
    }
    exposure_time_raw = camera.ExposureTimeRaw.GetValue();
    ~
    ~
}

A wrapper class defined at the out of main loop as follows is required for all methods in all different classes because the class type is also different.

std::function<void(double)> setExposure;
std::function<double(void)> getExposure;

GenApi::INodeMap& nodemap = camera.GetNodeMap();
if (GenApi::CIntegerPtr(nodemap.GetNode("ExposureTimeRaw")).IsValid()) {
    GenApi::CIntegerPtr node = nodemap.GetNode("ExposureTimeRaw");
    setExposure = [node](double v) {
        node->SetValue((int64_t)v);
    };
    getExposure = [node]() -> double {
        return (double)node->GetValue();
    };
}
else if (GenApi::CFloatPtr(nodemap.GetNode("ExposureTime")).IsValid()) {
    GenApi::CFloatPtr node = nodemap.GetNode("ExposureTime");
    setExposure = [node](double v) {
        node->SetValue(v);
    };
    getExposure = [node]() -> double {
        return node->GetValue();
    };
}

Then, we can keep a cycle speed of the main loop as follows.

while (1) {
    ~
    ~
    if (epics_exposure_time_raw_set > 0) {
        g_print("Setting exposure time: %f\n", epics_exposure_time_raw_req);
        setExposure(epics_exposure_time_raw_req);
        exposure_time_raw_set = 0;
    }
    exposure_time_raw = getExposure();
    ~
    ~
}

For (*1), replacing method directly seems to work fine like as follows.

   if (version=1) x = camera.GevCurrentIPAddress.GetValue());
   elif (version=2) x = device.GevIpAddress()

KAGRA/Subgroups/DGS/Projects/Cam/BaslerV2Camera (last edited 2026-02-18 21:15:03 by TakahiroYamamoto)