Electronic Endoscope Color Image Processing Technology

In this paper, we studied and analyzed the structure and special requests of image processing system in medical endoscope. And we also studied image processing theory and arithmetic of medical endoscope system such as chrome transforming, non-line distortion correction, white balance processing etc. We compared an endoscope system assembled by some domestic company and images it captured with others produced by a foreign company. We found that there are lots of problems in these images such like high frequency noises and low resolving ability.We went deep into the image processing module of medical endoscope system to analyze its important function in the system and its special requests when planted into the special circumstance of endoscope system. In aim of satisfying these special requests, we developed our own embedded hardware platform for image processing. This platform has six major parts including Charge Coupled Device(CCD) and its driving circuit, CCD's analog signal transforming module, image data storing module, bus interface management module, Digital Signal Processor(DSP) and its image processing module, video composing module. Using signal integrality theory, we analyzed our circuit. And the analysis gives problems that hardware platform may come to in such a special application. And the analysis comes to conclusions on how to avoid or settle these problems. We designed system's timing and driving program using hardware describing language, after analyzing the driving timing requested by the whole system. The driving program includes driving signals generation program for the CCD, synchronization timing signals generation program for the analog sample and transforming, whole system's synclironization signals generation program. We also designed color space transforming program for image pixels captured by CCD. After timing simulation, the program had been downloaded into FPGA to run practically. The driving pulse its generated had been recorded. The results declared that our program can satisfy both the CCD's and the system's needs.