How to pass generated image/bitmap/GDI objects to other process?

Question

I have a process A that generates HBITMAP GDI objects to be painted on the screen. I have another process B which wants to display the content of images that process A creates.

I plan to do the communications/talking using Point-to-Point message queue or by using other message passing; and use shared memory (along with mutex and or events) to share data.

How do I share image data? I read here that the handles of GDI objects are not guaranteed to be shared amongst processes. Sharing using files is not really an option since the images keep changing (but I still consider it if there is no other way).

Adding more to the ingredients, process A is written using eVC4 (PPC2003 SDK) and process B is written using VS2005 (WM 6 Pro SDK). I have working source code of both applications so I can make some modifications to both but not migrating app A to VS2005 for the time being.

Is COM IImage an option?

I prefer native codes but also consider managed codes.

Answer 1

Use CreateDIBSection with a shared memory object HANDLE as the section handle. The HBITMAP you get back from CreateDIBSection may not be sharable with the other process (I don't know), but if the other process ALSO Creates a DIB Section from the same shared memory object, then the bitmap bits will be shared.