Fig. 5From: A study on different experimental configurations for age, race, and gender estimation problemsHOG extraction features representation: image is divided into cells with size of N×N pixel each one (a). The orientation of all pixels is computed (b), and the histogram of the orientations of the cell is built (c-d). Finally, all the orientation histograms are concatenated in order to construct the final features vector (e)Back to article page