Can I Show preview screen when taking photos by python?

[Skullface9512]

Hi, in python tutorials, i know that how to set some relative properties and grab images. To know that what the environment i'm grabbing, i always open the IC Capture 2.5 and it's very troublesome, can i get image data from buffer directly using python and show it by opencv

[TIS-Tim]

If you want to display an image buffer using OpenCV, you can call numpy_wrap (or numpy_copy, if the buffer's pixel format is not directly supported) on it and pass the result to imshow as shown here.

You can also create an ic4 display and manually select which buffer should be displayed on it as shown in this example.

Finally, if you happen to use Qt (PySide6) you can embed the display into your application window as shown here.

(The latter example should really be using the (new in 1.1) imagingcontrol4.pyside6.DisplayWidget, it needs an update.)

[Skullface9512]

Hi, I have another problem, I need to adjust the camera's focal length through python script, do you provide some relative interface in python

[TIS-Tim]

For focal length adjustment via software you do need a zoom camera.

If you have one of those, it will be as simple as this:

grabber.device_property_map.set_value(imagingcontrol4.PropId.ZOOM, 123)

Here 123 is the logical zoom value. If you have a 39G camera, to get an approximate focal length of that number, have a look at the camera's technical reference manual.

[Skullface9512]

The camera i used is DFM 37UX178-ML, can i adjust its focal length through the method you describe above.

[TIS-Tim]

No. Focal length is a hardware feature of the lens. If you want to adjust focal length via software, you need a motorized lens.