In general, I like Adrian's site but over the years he has been locking more and more content (even blog posts that used to be available in the site) behind his

In general, I like Adrian's site but over the years he has been locking more and more content (even blog posts that used to be available in the site) behind his courses. Not that there's anything wrong with charging for knowledge (you know, teaching and getting paid for it), but it's a shame that things that used to be available, and of great quality, have been "pay-walled" somehow. Another good resource is https://learnopencv.com/ https://learnopencv.com/ . Again, good quality stuff, if you know your ways it tends to be enough[0] but it's also a big funnel to get you to but one of their courses. [0] though Satya Mallick does hide a lot of complexity from the readers, and that bites you if you try to implement things on your own