Abstract: To overcome the effect of edge defects and blur in image scaling,this paper proposes an adaptive Catmull-Rom spline interpolation algorithm for image scaling.The algorithm uses the cubic Catmull-Rom spline to interpolate pixels.Suitable pixel groups are automatically selected for interpolation.This paper emphasizes on the hardware implementation of algorithms used in image scaling,and the functional simulation of the scaler.Finally,the scaled image is further enhanced with sobel edge detection function.The results show that the algorithm can obtain the true edge of a clear target image color.