Cameras

A camera is an instrument that can be configured to get a live image of the current device under test.

Refreshing time

In order to display a live image, a refreshing time is set to hundreds of milliseconds by default. This value can be overrident in the configuration file through the camera.refresh_interval key with a value given in milliseconds.

USB Camera

USB Cameras are supported thanks to OpenCV library.

In the configuration file, you have to specify the camera.type to USB.

If your computer has multiple cameras connected, you may have to specify the camera.index that will be given to OpenCV’s VideoCapture() function during the instantiation of the camera. On linux system, it corresponds to the number appending /dev/video device.

REST Camera

If you have a service providing pictures with a REST interface, you can use it to use as a Camera object in Laser Studio.

In the configuration file, you have to specify the camera.type to REST.

You have also to specify the host, the port and the path of the URL to get the image to be shown in Laser Studio, with the camera.host, camera.port, and camera.api_command keys in the Configuration File.

Note that the fetching of the image may take a certain time due to network latency. This is why the refreshing time is set to higher that the default one.

Pixel Size

In order to display the camera’s image to the correct size in the Viewer, Laser Studio needs to have a hint on the size of a pixel, in micrometer. You can give this information in the confiugration file, with the camera.pixel_size_in_um key by giving an array of two decimal values (first one for the horizontal ratio, and second one for the vertical ratio).

Negative values can be given if you need to flip the image of the camera.

Objective

In the case where the camera is mounted on a optical column, the camera.objective key in the Configuration File can set which objective is used to magnify the image in the optical column.

Configuration file examples

Here are some examples for defining the configuration of the Cameras in the configuration file. To get more information about it, see Configuration File.

For a REST Camera

camera:
    enable: true
    type: REST
    refresh_interval: 1000
    api_command: "images/camera"
    pixel_size_in_um: [15.115, 15.115]
    objective: 5

For an USB Camera

camera:
    enable: true
    type: USB
    index: 0
    pixel_size_in_um: [120, 120]