Aspect ratio in Calibration [ ChArUco Board ]

hi :grinning:

how i can calculate “aspectRatio” for my webcam? i need aspectRatio for calibrate my webcam [ The following project ] :
opencv_contrib-4.5.5\modules\aruco\samples\calibrate_camera_charuco.cpp

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Is it obtained from the following equation?
My webcam resolution is 1920x1080 —then—> 1920/1080 = 16/9 = 1.777777777777778

aspect-ratio-2

Did I get it right?