Mastering OpenCV 4 with Python

Understanding cv2.dnn.blobFromImage()

In Chapter 11, Face Detection, Tracking, and Recognition, we have seen some examples involving deep learning computation. For example, in the face_detection_opencv_dnn.py script, a deep-learning based face detector (https://github.com/opencv/opencv/tree/master/samples/dnn/face_detector) was used to detect faces in images. The first step was to load pre-trained models as follows:

net = cv2.dnn.readNetFromCaffe("deploy.prototxt", "res10_300x300_ssd_iter_140000_fp16.caffemodel")

As a reminder, the deploy.prototxt file defines the model architecture, and the res10_300x300_ssd_iter_140000_fp16.caffemodel file contains the weights for the actual layers. In order to perform a forward pass for the whole network ...