【摘要】 在图像传输系统中,用光学方法实现图像的小波变换具有并行性和高速实时性的特点,在制作用于图像小波变换的光学滤波器时,会引入人为的或者硬件等带来的误差,所以需要测量光学滤波器的误差,从而在设计时补偿误差。本文对胶片滤波器的精度进行了实验分析,研究结果表明:以24 bit的彩色图像为分析基础,胶片制作图像的灰度级与原始图像的灰度级间并非线性对应,R、G、B三通道的精度略有差异。经多项式拟合对均值进行补偿后,其平均峰值信噪比可提高10～20 dB。更多还原

【Abstract】 Optical wavelet transform has the advantage of parallel,real-time and high speed in image transmission system.Considering inaccuracy brought by man-made factors or hardware devices in the facture of optical filter,it is necessary to measure the error of it.This paper analyses the principle,facture and the error of filter made of film for optical image processing.It is verified by lots of experiments that based on color images of 24 bits,the relation between original image gray level and the one made of film is non-linear,and gray levels of film image varies with different grey level combination of R、G、B channel.Meanwhile,the precision of each channel is different.The performance of R channel is the best,and B channels’ is the worst.By polynomial curve fitting,the PSNR(Power Signal-to-Noise Ratio) of film will increase 10～20 dB.更多还原