Creating a Dib by only specifying the size with GDI+ and DotNet...

Question

I have just recently discovered the difference between different constructors in GDI+. Going:

var bmp = new Bitmap(width, height, pixelFormat);

creates a DDB (Device Dependent Bitmap) whereas:

var bmp = new Bitmap(someFile);

creates a DIB (Device Independent Bitmap). This is really not usually important, except when handling very large images (where a DDB will run out of memory, and run out of memory at different sizes depending on the machine and its video memory). I need to create a DIB rather than DDB, but specify the height, width and pixelformat. Does anyone know how to do this in DotNet. Also is there a guide to what type of Bitmap (DIB or DDB) is being created by which Bitmap constructor?

Answer 1

It appears the best way to do this is to allocate the memory yourself, and then then create the bitmap with:

var bmp = new Bitmap(width, height, stride, format, scan0)

This way you can create huge bitmaps without having an out of memory error.