Bitmap biHeight Negative or Positive?

[lily311]

As I observed, most bitmaps are bottom-up DIB and the biHeight
of BITMAPINFOHEADER are positive. After scanned a bitmap,
I have to save the RGB data in a top-down way because of time issue.
So I set the biHeight negative. If I double-click the bmp file
directly, it can be shown correctly, but can't load it with ::LoadImage();
If I change biHeight to positive, I can load it with ::LoadImage(),
but the bitmap is upside-down.

Any help be appreciated.

[lily311]

???

[Dave McLelland]

Does the LoadImage fail?
Whats the error returned from GetLastError()?

[lily311]

VC Debug Window said:
HEAP[test.exe]: Invalid allocation size - FFF84800 (exceeded 7ffdefff)

GetLastError() returns 0x0008. That is Not enough storage is available to process this command.

My bitmap width: 658, height: 256. I think, when I set the height negative, LoadImage() still treats it as unsigned data, and gets the bitmap size by width*height. That's a too huge size.

[Dave McLelland]

Please post your call to LoadImage and any other relevant code. Post the bitmap too if possible.

[lily311]

Hi, Dave McLelland:

Thanks for your kindness and help.

I rearranged the bmp data in the bottom-up way, kept the height positive, and solved the problem with LoadImage.

But the problem I've mentioned above Does exist. If you still wondered, just modify any bmp to a negative height, load it with LoadImage, and I believe it will return NULL.

Anyway, if you get different result, kindly let me know please.

Regards & Thanks,
Lily311

[agromatic]

Hi All,

I'm wondering if any more light has been shed on this issue (I realize it is a very old post)? I started running into it recently pretty consistently on XP and even occasionally on Vista with very small bitmaps.

Just the normal LoadImage code:

hBitmap = (HBITMAP)LoadImage(NULL, szFileName, IMAGE_BITMAP, 0, 0, LR_CREATEDIBSECTION | LR_LOADFROMFILE);

Any insight would be helpful. Thanks!