How to specify offset for the buffer

[YGCuber]

I just started to learn how to use vuh. The library is easy and smooth.
But I have the question. I would like to use one big buffer as Array that contains the group of images (not one).
How to specify offset to the image N in the buffer, to process it by kernel?
So I have one block of the memory that I pass to the shader but inside I need to know what data to process.
I don't wont to reject invokation if the current invocation offset is out of the image N, it is the bad way. There is should be another solution, I think.