The documentation says this is similar to GL_MIRRORED_REPEAT. I tried to research this, but it doesn't seem as specific as the OpenCV border types.
gfedcb|abcdefgh|gfedcba, this is the default.fedcba|abcdefgh|hgfedcbI guess the corners are not strictly defined by this, but I can clearly see what the edges are. The documentation for GL_MIRRORED_REPEAT seems to focus on corner behaviour. Overall, it does not matter with our application as there are physical limitations on the targets of interest that keep them within the bounds of the field of view. However, if I am writing regression tests and these specifics matter.
How can I replicate BORDER_REFLECT_101 in Halide? Is it possible with Halide::BoundaryConditions or do I need to implement my own clamping? I can relax the conditions after proving we have replicated behaviour and use Halide::BoundaryConditions::mirror_image.
Bonus: Is Halide::BoundaryConditions more performant than using clamp or is this just syntactic sugar? It seems the opposite; it is better to use clamp?
Bonus: Is Halide::BoundaryConditions more performant than using clamp or is this just syntactic sugar? It seems the opposite; it is better to use clamp?
The boundary conditions are just a convenience. They're implemented here. They should be no more or less performant than writing the same yourself since they're just metaprogramming Exprs (i.e. they aren't compiler intrinsics).