基于DSP的实时图像复原

Real time image restoration based on DSP

选用 TMS320DM642作为处理器开发了图像退化仿真和复原系统。可以实现图像采集、退化仿真、逆滤波和维纳滤波复原。在软件设计中采用多种优化措施,如合理分配内存,二维数据片外存储,功能强大的 Image Lib 库函数调用,DMA 方式实现片内、外存储器之间的数据交换;行列算法实现二维 FFT;在复原时用定点乘法代替耗时的浮点除法运算;通过合理定标确保二维 FFT 和 IFFT 过程不产生溢出;模板平滑取代卷积加快图像模糊运算;使用内联函数、循环展开、软件流水、编译选项等,这些措施的应用,大大减小了运算量,提高了处理速度。对256×256图像进行的模糊、逆滤波和维纳滤波复原运算,帧率达到10帧/s.

An image degradation emulation and restoration system are described that uses TMS320DM642 as processor.In the software programming,a series of optimizing means are used,such as allocating memory properly, exchanging datum between the inside and outside memory via DMA mode;accomplishing 2DFFT with line-row arithmetic;employing dichotomizing comparing method to process extraction;using fixed dot multiplication instead of floated dot division;deciding mark properly to insure not overflowing in two-dimension FFT and IFFT process; using template smoothing rather than convolution to speed the blurring operation.All this measures reduce operation quantity and improve processing speed greatly.For 256×256 image,the system has achieved image capturing, blurring,inverse filtering and winner filtering restoration at the speed of 10 f/s.