Fast Scale-Space Feature Representations by Generalized Integral Images

In this paper, we place the integral image-based approach for multi-scale feature construction, popularized by Viola and Jones, into a common framework of understanding. The integral image within this framework represents space variant image filtering with the zero-order B-spline. Given this framework, we propose efficiently computable higher-order B-spline image features based on generalized integral images that have the potential to be more accurate, yet efficient as compared to previous integral image-based efforts.