将真彩色图像转为索引图像，压缩很有用的图像，希望大家喜欢！-true color image to image indexing, compression useful images, hope you like them!

The indexing of an image database is often referred as feature extraction. Mathematically, a feature is an n-dimensional vector, with its components computed by some image analysis. The most commonly used visual cues are color, texture, shape, sp