本程序主要是对桌面进行截屏，为命令行工具，将截屏保存为jpg文件。-The program mainly for desktop screenshots, for the command-line tool that will save the screenshot as a jpg file.

实现了类似QQ的截图功能，可以截取窗口区域，保存为bmp-Achieve a similar QQ screenshot function, can intercept window area, saved as bmp