Design Of Video Coding System In Multimode Space Digital Camera

With the rapid development of China’s space technology, Not only do the need of digital video and image processing systems in space applications is increasing, but also the requirements of function and efficiency on the digital video and image processing system are higher. At the same time, due to the high complexity of the space environment, the digital video and image processing system should work stably and reliably under such conditions, while providing high-quality encoded images. Therefore, it has become a research hotspot to design a multi-mode and high reliability digital video and image processing system which can adapt to the space environment. Based on the practical application of the field of aerospace,a suitable multi-mode digital video and image compression coding system is put forward by targeted researching and studying. The author’s major contributions are outlined as follows:First, the current development status of the digital video compression and image processing system in the aerospace field have been studied, and the current development situation of the field programmable logic devices and digital signal processing devices which can be applied to the aerospace applications have been analyzed. Based on the analysis of the ultra-large-scale programmable logic device FPGA and high-performance digital signal processing unit DSP, the corresponding FPGA and DSP selection strategies and feasibilities are given.Secondly, the related pre-processing algorithms of the digital image processing have been researched deeply. And the hardware language description and simulation verification have been used for the algorithms of color interpolation and color space conversion which have been applied to the practical system finally. Based on the study of the H.264/AVC high-performance video coding standard and the JPEG2000 still image coding standard, this paper introduces the encoder structures and compression processes. Combined with their own characteristics and the selected devices, the advantages of the two algorithms for this system have been analyzed.Finally, A space multi-mode digital camera video encoding system has been designed for the actual space application, on the basis of the FPGA and DSP technologies, pre-processing algorithms and the H.264/AVC and JPEG2000 coding standards. Thissystem has been also realized and verified on the hardware platform. In this paper, the elaborate efforts are made to introduce the design of FPGA functional modules. Moreover, the performance of the entire system has been assessed, and the actual results are presented at the end of this paper.