This is a fairly short, haphazard intro to OpenCV for Python. It starts out with image processing functions and moves into more sophisticated uses like object detection and recognition and neural nets. Each chapter starts off with a description of what we're trying to do and the tools that we'll use to do it. These runs of prose can be quite effective, and show that the authors are quite capable. Unfortunately, the coding part fails to match the quality of the overview summaries.
I buy books because online tutorials are often half-hearted, with blocks of unexplained code and paragraphs full of poor grammar. This book has okay grammar, and the descriptions of the algorithms and methods are often quite good, but at the end of the day, there's too little explanation of what's going on. Let me spell it out: C-O-D-E D-U-M-P-S! I used this book to get me started, but most of my effort in learning OpenCV came from online tutorials. It's a shame as the book obviously has potential.
I also tried to download the code from the book's website and failed miserably. The publisher makes it hard to do. They should follow the example of the No Starch Press and provide a link to a public GitHub site. They want to ensure that you bought the book, which might be easy if you bought directly from Packt, but not if you bought from Amazon or a bookstore. As a result, I will be very careful about buying Packt books in the future.