Images are hardware textures and at least the OpenGL ones do not exist as textures in system memory anymore. Pro point is that you only need to send an int but are forced to use OpenGL commands ...
The DX ones are DX Surfaces and thus handled by DX on its own, so you should be able to send a BytePtr to the Surface structure
Might I ask, what reason you have to pass it to a DLL instead of performing the operation within BM? (Implementation for GLEW and DX9 are present)
The DX ones are DX Surfaces and thus handled by DX on its own, so you should be able to send a BytePtr to the Surface structure
Might I ask, what reason you have to pass it to a DLL instead of performing the operation within BM? (Implementation for GLEW and DX9 are present)