A method to reduce number of division operations for perspective texture warping

Perspective texture warping is an important and a computation-intensive function. It is explicitly specified in the MPEG-4 video standard for Sprite decoding and for the MPEG-4 compositor. Based on the incremental algorithm of perspective transform, perspective transformation requires one division operation for each pixel, which is a substantial computation workload if such function is implemented in hardware for real-time processing. In this paper, we discuss a new method we have developed to reduce the number of divisions for perspective transformation in macroblock-based operation to as low as one quarter of the number required. In addition, our method is a lossless method. Therefore, less complexity in the implementation of perspective transformation can be achieved without sacrificing the picture quality of the warped texture. We believe that our new method is very useful in restraining the complexity of perspective transformation