关键是你要搞懂bmp图像的结构。
首先是一个文件头
struct tagBITMAPFILEHEADER {
unsigned short bfType;
unsigned long bfSize;
unsigned short bfReserved1;
unsigned short bfReserved2;
unsigned long bfOffBits;
}
接着是一个位图信息
struct tagBITMAPINFOHEADER{
unsigned long biSize; // 文件大小
long biWidth; // 图像宽度(像素)
long biHeight; // 图像高度(像素)
unsigned short biPlanes;
unsigned short biBitCount; // 每像素占用位(类型),1位=单色,4位=16色,8位=256色,24位=真色彩
unsigned long biCompression;
unsigned long biSizeImage;
long biXPelsPerMeter;
long biYPelsPerMeter;
unsigned long biClrUsed;
unsigned long biClrImportant;
}