13.1 灰度变换增强 13.1.1 像素值及其统计特性 13.1.2 直方图灰度变换 13.1.3 直方图均衡化 13.1.4 直方图规定化 13.2 空域滤波增强 13.2.1 平滑滤波器 13.2.2 锐化滤波器 13.3 频域增强 13.3.1 低通滤波器 13.3.2 高通滤波器 13.3.3 同态滤波器 13.3.4 频域增强 MATLAB 实例 13.4 色彩增强 13.4.1 真彩色增强 13.4.2 伪彩色增强 13.5 小波增强-13.1 13.1.1 pixel gray-scale transformation enhance the value of its statistical characteristics 13.1.2 histogram gray transform 13.1.4 13.1.3 histogram equalization histogram provides enhanced spatial filter 13.2 13.2.2 13.2.1 sharp smoothing filter Enhanced frequency domain equalizer filters 13.3 13.3.1 13.3.2 lowpass filter high-pass filter 13.3.3 13.3.4 homomorphic filter frequency domain enhanced color enhancement MATLAB Examples 13.4 13.4.2 13.4.1 true color enhanced pseudo-color enhancement 13.5 wavelet enhancement