Mastering OpenCV 4 with Python

Argparse – command-line option and argument parsing

It should be taken into account that we should not handle sys.argv directly, mainly when our programs take complex parameters or multiple filenames. Alternatively, we should use Python's argparse library, which handles command-line arguments in a systematic way, making it accessible to write user-friendly command-line programs. In other words, Python has a module called argparse (https://docs.python.org/3/library/argparse.html) in the standard library for parsing command-line arguments. First, the program determines what arguments it requires. Then, argparse will work out how to parse these arguments to sys.argv. Also, argparse produces help and usage messages, and issues errors when invalid ...