Question for opencv experts?

Question

Python

I am learning to write scripts for face recognition. Opencv module, written in Python. I just learned about the scaleFactor parameter of the detectMultiScale() functions, the question immediately arose: how to make the values ​​of this parameter change if there is no face in the photo. Of course, I wrote something for this. But I feel like I'm doing something wrong. How can I make the values ​​change themselves. Is there something ready for this?

Answer 1

Themselves - no. Choose once the value for your task, and leave it.
scaleFactor is the scale step when looking for objects of different apparent sizes.
The closer it is to 1, the smaller steps the algorithm takes, the more these steps, the longer the image is processed. The larger it is, the faster the processing - but at the same time, the face of the "intermediate" size between a couple of steps can be lost.
It should be noted that a face can be "lost" not only because of this parameter, but also because of many other factors.