def readBMP( filename):
f = file( filename)
content = f.read()
f.close()
return content
def getDimensions( bytes):
return bytes[18:22],bytes[22:26]
w,h = getDimensions( getBMP( 'test.bmp'))static int fourchar2int(unsigned char b0, unsigned char b1, unsigned char b2, unsigned char b3)
{
if (b3 & 0x80) {
return (~b3 & 0xff) * -16777216
+ (~b2 & 0xff) * -65536
+ (~b1 & 0xff) * -256
+ (~b0 & 0xff) * -1
- 1;
} else {
return b3 * 16777216
+ b2 * 65536
+ b1 * 256
+ b0 * 1;
}
}
...
struct {
int a;
int b;
} d;
unsigned char buf[8];
...
fread(&buf, 1, sizeof(buf), pfile);
d.a = fourchar2int(buf[0], buf[1], buf[2], buf[3]);
d.b = fourchar2int(buf[4], buf[5], buf[6], buf[7]);
...
... d.a ...
... d.b ...