图像格式的转换，首先要准备一张图片，和几个txt文档，把txt文档的扩展名改成一个你要把图片转换成的格式，我用的原始图片是jpg的，txt改成bmp的 -Image format conversion。We must first prepare a picture, and several TXT documents, the txt file extension of the one you want to convert the format I use the original i