My DIBs are 2 Bytes Short

[endemoniada]

Hi guys,

I noticed that my DIBs, both saved and copied to the clipboard, are 2 bytes short.

DWORD dwSize=sizeof(BITMAPINFO)+height*span;
HGLOBAL hGlobal=GlobalAlloc(GMEM_MOVEABLE,dwSize);
LPBYTE mem=(LPBYTE)GlobalLock(hGlobal);
...
// fill in BITMAPINFO
BITMAPINFO* bmi=(BITMAPINFO*)mem;
...
// copy bits
LPBYTE bits=mem+sizeof(BITMAPINFO)+2;
// if I don't add the +2 the colors are shifted
...

Where are those 2 bytes coming from ?

My filesize is always 2 bytes smaller than the same bitmap saved in Photoshop, and if I copy to clipboard the colors are shifted by two bytes (red is blue, green is red, blue is green.)

Thanks

[S_M_A]

See this http://msdn.microsoft.com/en-us/libr...(v=VS.85).aspx under remarks.

The bitmap data has to be LONG or DWORD aligned (both 32 bits) so I guess that sizeof(BITMAPINFO) is not a multiple of 4 bytes.

[MikeAThon]

In addition, " each scan line must be padded with zeros to end on a LONG data-type boundary", so height*span might be wrong if you are using a color table and indices into the color table.

Of course, if you are using RGBQUADs, then height*span is automatically fine.

Mike