Learning OpenCV 4 Computer Vision with Python 3 - Third Edition

Saving image descriptors to file

The first thing we will do is save the image descriptors to an external file. This way, we don't have to recreate the descriptors every time we want to scan two images for matches.

For the purposes of our example, let's scan a folder for images and create the corresponding descriptor files so that we have them readily available for future searches. To create descriptors, we will use a process we have already used a number of times in this chapter: namely, load an image, create a feature detector, detect features, and compute descriptors. To save the descriptors to a file, we will use a handy method of NumPy arrays called save, which dumps array data into a file in an optimized way.

The pickle module, in the ...