卫星遥感图像的量化等级确定及影响因素分析

在分析人眼视觉特性的基础上,提出图像量化位数的选择取决于图像的最终用途的观点.从天基预警类成像探测仪的基本原理出发,建立了信噪比与探测概率之间的关系,进而研究了量化级数确定问题.就图像显示和人眼观看而言,8 bit量化已能满足要求.当用于预警和目标探测目的,在满足信息处理需要前提下,虚警不超过10－4/Frame边界条件下的最小量化级数可进一步降低为5 bit,较理想的量化级数为6 bit.

Pixel-quantization and Its Influence for Remote Sensing Image

According to the features of human′s vision,it is deduced that gray scale level of an image should be decided for various usages.Based on the detecting principle of space borne IR camera for early warning satellite,a calculating model for signal to noise ratio and detection probability is established.Effect to the image with different digital length of pixel-quantization is discussed.Results show that 8 bit of pixel-quantization of an image is sufficient for human′s visual recognition.When images are used for the detecting of a boost phase missile or other burning targets,6bit pixel-quantization will be better,though 5 bit pixel-quantization is the minimum digital length to get 10－4/Frame detection probability.