Omnidirection Image Restoration Based On FPGA

Because of its advantage of panoramic sight with a single compact visual scene, Omni-directional vision technology has extreme application value in many fields. One of the most effective ways to establish Omni-directional vision system is using fisheye lens. However it brings a strong unavoidable inherent distortion while it provides hemispherical field of view. But it can be corrected by some image processing techniques. Usually the algorithm is implementing by software on PC, but its processing speed is too slow for some applications, which need the real time image information.By the developt of the Integrated Circuits, the integration of the circuit is larger than larger.Now a complicated system can be designed in a single chip. Especially the develop of the FPGA (field programmable gate array), DSP (digital signal processor), ARM(advance RISC machine), which bring the large changes in video and audio processing. So the embedded system has become the hot issues of the field of Eleetronie Design Automation (EDA). Embedded systems can not only reduce the power dissipation and the volume, but also raise the integration of the system. It results in high competence of produets in market. Because of the parallel structures of the algorithm, the FPGA is fit for this application which has the parallel structures.According to the characteristics of the fisheye lens, an algorithm, which is fit for FPGA to implementing, of the rectifition of the fisheye lens image based on spherical perspective projection is proposed. And then confirmed the parameter of the algorithm needed.By analyzing the algorithm and the real problem, the system is dividing into receive and transmit modules, data storage module, image corrected module for FPGA to implement. The data input from the serial port and then storage in the DDR-SDRAM. When one image is transmited the corrected module start to work, it correct the input image and store the new image into the memory, the transimit module output the data at last.Confirmed the blue print of the system, veilog HDL is selected to implemt the logic module in the FPGA, the serial port module, the storage module and the image corrected module are assigned to implement their logic function.According to the simulation software, all modules are running corrected in the FPGA and the design is verified to suffice for the required of the applications.