Design Of A Medical Endoscope Camera System Based On ARM And FPGA

Medical endoscopic camera system, which was a kind of medical equipment in thefield of digital image, was used to obtain more human physiological information. But,there was a shortcoming of bulky volume. Along with the development of electronicinformation and embedded technology, the modern medical equipment would betowards the direction of enhancing function and reducing the size of medical devices. Inthis paper, the functional requirements of medical endoscopic camera system wereanalyzed. After a comparative study of the technical status of endoscopic camera systemat home and abroad, a design scheme of medical endoscopic camera system which useda combination of ARM and FPGA was proposed. A CCD camera was used to capturethe image of endoscope in this system. The core components of the system were FPGAand ARM chips. Powerful parallel processing capabilities and rich hardware resourcesin FPGA were utilized to achieve image processing, and emedded system in ARM wasused to realize human-computer interaction.First, the overall design of a medical endoscope camera system based on ARM andFPGA was described. Secondly, the concrete implementation of the camera and theprinciple of image freeze were studied using FPGA. The measures include digital videostream decoding of ITU-R BT.656, the start detection of image frame, image freezingand displaying, and so on. Thirdly, a color interpolation algorithm based on slidingwindow was used to complete re-sampling from YCbCr4:2:2to YCbCr4:4:4. Inaddition, on the basis of studing of communication of ARM and FPGA, the driverprogram which realized interface communication of ARM and FPGA was developed.Concrete realization of communication was explained. FPGA was connected to thesystem bus of ARM as a peripheral storage device of ARM. The linux system wouldread or write FPGA data through the driver developed by this paper.Experimental results show that several parts of the work have been accomplished，including image freezing and playback, image data real-time display and storage and soon. The image data of freezing could transmit from FPGA to ARM. Few resource ofFPGA occupied by the system provided a possiablility for the subsequent imageprocessing development. In addition, this system is demonstrated to be structuralsimplicity, low cost, space saving, and high design flexibility.