Research And Implementation Of Image Enhancement System Based On DSP

An image system consists of acquisition, transmission, reception and display, every part of which can be disturbed, so that the image equality can be degraded. Elementary requirement of image enhancement is how to deal with these degraded images to meet our need. One of main contents of image processing is image enhancement. Image enhancement is one essential technique of the digital image processing techniques. It is an important link in the image processing system. Moreover, its result has direct relations with advanced processing and understanding of the image.We developed a low-cost images enhancement system based on DSP according to image-processing features. The system uses a CCD camera as imported equipment, uses DSP as image processing arithmetic unit, and the CPLD as the timing and logic controller. The image enhancement algorithm enhances the images collected, which send to PC by UART. Main elements are as follows:(1) The hardware design of the image enhancement system. Including the realization of the DSP system power supply, clock, external memory extending, image collecting and data translating.(2) Discussing the implement of image collection base on CPLD, SAA7111A and FIFO. It is include SAA7111A's initialization that is overcome by virtual I2C—BUS interfacing design and timing control of image collection by CPLD.(3) A software realization method of Boot Loader, system initialization, and serial communications is given.(4) A combination image enhancement algorithm is proposed in this system, which is the combination of histogram modification and high-frequency emphasis filtering. This algorithm can remedy the deficiency of the balanced method of the enhancement equalization, and can strengthen the detail of image. Flow chart and experimental results are shown finally.