1. A method for determining whether a person is present in an image, comprising: receiving a plurality of images, wherein each image comprises a plurality of pixels; determining a modified center symmetric local binary pattern (MS-LBP) feature for the plurality of pixels for each image, wherein the MS-LBP feature is calculated on a gradient magnitude map without using an interpolation process, and wherein a value for each pixel is a gradient magnitude; and determining that the person is present in one of the images in accordance with the MS-LBP.