Where is the "z" crop used?

[vinceyoung]

Hello,

Thanks for sharing your great work! I see that the dataset preparation scripts write an "x" and a "z" image to disk, but here it looks like the dataset uses the "x" image for everything, rather than making use of the "z" image for template, which I believe may have been intended. Is that correct? If not, what is the "z" crop used for?

Thank you!