In this paper, a digital image measurement method based on embedded DSP system is proposed to achieve automated and high-speed measurement of shower spray angle, with edge detection and Hough transform operations in mathematic. The application of digital image measurement method solved the problems exist in traditional spray angle measurement field, which not only improved measurement accuracy and speed, but also simplified operations. And as an embedded DSP-based system, it has a lot of advantages, such as compact size, fast calculation and so on. With modification firmware, this DSP-based system can be used in a variety of image processing field.