An embedded three-dimensional (3D) imaging system based on digital signal processor (DSP) is presented. The hardware platform of this prototype is composed of fringe projection, data acquisition, automatic fringe analysis as well as other supporting circuits and memories. The fringe projection module encoded the fringe patterns that is realized by the DSP software, and projected it on object surface through the digital light projection (DLP) to create structural light illumination. The deformed fringe patterns reflected from object surface is detected by a CCD camera and then acquired by data acquisition module that decodes the video signal. The module of automatic fringe analysis is utilized to demodulate the phase distributions of deformed fringe patterns with phase shifting technique, and followed by a phase unwrapping procedure to create continuous phase maps that correlate the height variation of object surface. Three major modules are controlled by the multi-thread technique to accomplish multi-tasks in a parallel fashion. The phase demodulation algorithm, the most time-consuming calculation, is optimized by the software pipeline combined with other strategies such as loop unfolding, data prefetching and inline functions, etc. Experimental results show that the proposed approach can implement the 3D shape measurement with fast speed and good accuracy. The optimized speed of phase unwrapping program is 7 times faster than it before.