Help in understanding algorithms

Hi ! I've doing some research on algorithms that track an object on a given video, without using AI. So far I've encountered 2 major techniques :

\- Analysis of the optical Flow : methods such as the Lucas-Kanade or the Horn-Schunck algorithm

\- Kalman's Filter that from what I saw uses probabilities

Although I found those methods, I didn't understand how they work, and I need something quite precise, not a mere explanation, the websites that I visited were …

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