December 2018
Intermediate to advanced
280 pages
7h 23m
English
Content preview from Mastering OpenCV 4 - Third Edition
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Detecting the face
Now that we have converted the image to grayscale, shrunk the image, and equalized the histogram, we are ready to detect the faces using the CascadeClassifier::detectMultiScale() function! There are many parameters, listed as follows, that we pass to this function:
- minFeatureSize: This parameter determines the minimum face size that we care about, typically 20 x 20 or 30 x 30 pixels, but this depends on your use case and image size. If you are performing face detection on a webcam or smartphone where the face will always be very close to the camera, you could enlarge this to 80 x 80 to have much faster detection, or if you want to detect far away faces, such as on a beach with friends, then leave this as 20 x 20.
- searchScaleFactor ...
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