I am working on a bitmap enlarger program. This is my second topic this week. When I look at the bitmap structure on Wikipedia (https://en.wikipedia.org/wiki/BMP_file_format) it shows hex values such as : 46 00 00 00. This represents that the size of the bmp being 70 bytes (offset 2h.) This shows that the remaining three zeros are nothing but placeholders. Now, what if I need to use a zero that actually changes a hex value, how would this be done? I am writing it to a file.

Thank you,

Josheir

This is the file write for some string hexbuffer such as : 0100FFA0.

ofstream myfile;
myfile.open("C:/Users/joshe/file7.bmp", ios::binary);  
for (int i = 0; i < 8; i++)
{
r = cal(hexbuffer[i]) * 16 + cal(hexbuffer[i+1]);
myfile << r;
i++;
}
myfile.close();

int cal(char c)
{
int h = 0;
if (c <= '9' && c >= '0') return c - '0';
if (c <= 'f' && c >= 'a') return c - 'a' + 10;
if (c <= 'F' && c >= 'A') return c - 'A' + 10;
return(1);
}

A more realistic value would be: 01000000.

Also, r is of type char.

Looks as though placing the zeros on the left might work. Still, I'd have to read though.