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Extract Images from Video Using OpenCV in Python

Tips and Traps

  1. Most videoes have a FPS of 24. Some videos have higher FPS (e.g., 30 or 60) so that they can capture motions better. A record video on a computer has a FPS of the refresh rate of the monitor, which is usually 60. You can get the FPS of a video using OpenCV in Python.

The list Collection in Python

Tips and Traps

  1. list is essentially a resizable array of objects in Python.

  2. Almosts all methods of list are in-place.

  3. list.pop is inplace and returns the removed element.

  4. To get unique elements in a list, you can first coerce the list to a set and then convert the set back to a list.

     unique_list = list(set(alist))

Working with Iterators in Python

Iterator vs Generator

Generator is a special case of Iterator. Generator is easy and convenient to use but at additional cost (memory and speed). If you need performance, use plain iterator (with the help of the itertools module). If you need convenience and concise code, use generator.

Please refer to Python Generator vs Iterator for more detailed discussions.