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()