Face location with LBP scale transform

Local Binary Patterns (LBP) is an effective texture description operator and the histogram that it generates has been proved to be a very useful texture feature to adapt to rotation and illumination. Using the LBP features as feature vectors in adaBoost classifier for target identification has become a trend. But LBP is bound by the scale transformation, so it is not widely used in adaBoost face detector. This paper proposes a scale transform formula for Local Binary Patterns. Based on this formula, LBP features extracted from single fixed size templates can be trained to identify any size of faces. This paper also proposes a method to obtain particular detecting sub-areas called binary ring-shaped sub-windows, which can keep the LBP features rotation invariant. Experimental results show that the method we proposed here is feasible in face detecting.