Image compression

A number of colors in a predefined region of an image to be compressed are determined. The predefined region has a plurality of pixels. In response to determining that the number of colors is greaterthan a first predefined threshold, a lossy compression process is selected dependent on a number of pixels in the predefined region having a predefined color. The selected lossy compression process isapplied to the predefined region. 确定待压缩图像的预定义的区域中的颜色的数目。所述预定义的区域具有多个像素。响应于确定颜色的数目大于第预定义的阈值，取决于具有预定义的颜色的预定义的区域中的像素的数目选择有损压缩过程。将所选择的有损压缩过程应用于所述预定义的区域。