中文摘要：

随着航天器载荷相机图像分辨率的日益提高,迫切需要解决海量图像数据的在轨高速编码处理问题,空间数据系统咨询委员会提出了一种面向空间应用的图像编码标准.为了保证较高的图像编码性能,该标准采用小波的变换方法.小波变换的多级变换形式比较耗时,且需要较大的存储开销.针对这一问题,提出了一种高效低存储离散小波变换的超大规模集成电路结构.通过改进传统的小波提升结构,将二三级变换和缓存结构进行复用,在不降低数据处理速度的情况下,节省了逻辑资源开销;使用少量片上存储资源存储部分小波系数,按特定顺序连续地输出给后级熵编码器进行处理,避免了使用片外存储.所提出的超大规模集成电路结构在Xilinx型号为XC4VSX55的现场可编程门阵列得到了硬件实现,具有95.91MPixels/s的数据处理性能.

英文摘要：

With the gradual increase in image resolution of the spacecraft camera,it is highly required to figure out the problem how to process a huge amount of image data on board at a high speed.As a solution,the CCSDS proposes a space-oriented image-coding standard.For the sake of high image-coding performance,it adopts wavelet transformation as a method of image data transformation.However,wavelet transformation contains multi-level data processing,which causes more computational time consumption and more memory utilization.In order to solve this problem,we propose a highly efficient VLSI architecture for DWT with low-storage.By revising the traditional lifting structure and employing time-multiplex data processing strategy to perform the second and third level of wavelet transformation by the same logic module,the usage of logic resource is reduced with no sacrifice on speed.Using a small amount of on-chip memory instead of off-chip memory to save certain parts of DWT coefficients and sending the coefficients in a specific sequence to entropy coder timely,the off-chip memory for storage of DWT coefficients is no longer required.The proposed VLSI architecture of DWT is already implemented on the Xilinx FPGA XC4VSX55,which can achieve a high performance,in terms of data throughput,reaching95.91MPixels/s.