What to read about pattern recognition?

Question

Programming

Hello.
What can be read on the methods of pattern recognition?
That is, we have a picture in the system, we need to recognize it when pointing the camera.
Interested not only in recognizing a static picture, but also in recognizing the object that the camera was aimed at, that is, when it is not clearly known what is currently on the screen and is there anything at all?
As I understand it (naturally, there are other methods, but this one may be incorrect / long) this can be implemented as follows: for the image that needs to be recognized (which we have in the database), a certain map of key points is built, by contrast, or by some then other indicators. This map is then saved as a hash to the database. When scanning, we perform the same operation every second with the image received from the camera and look for such a hash in our database. This is if very rude.
Machine learning, as I understand it, is not suitable here, because, at the time of loading the image, we do not know in what form it can be represented when it is visible through the lens. It can be shot sideways, from bottom to top, and so on.
Thank you!

Answer 1

An example of deep learning on MatLab. (toolbox Computer Vision)