We discussed region-based techniques for object detection in the There's more... section of the previous recipe, Object localization, of this chapter. However, numerous techniques are widely used specifically for human face localization.
Let's look at how some of these techniques work:
- HOG and SVM: They are used as a descriptor for image detection and work seamlessly with varying illumination backgrounds and pose changes. In this technique, the image is divided into 8×8 cells, and then the distribution of magnitudes and the directions of local intensity gradients over the pixels are obtained. Pixels with a large negative change in gradient will be black, pixels with large positive change will be white, and pixels with little ...
