Packages reference the old code.google.com/p/graphics-go/

[carbocation]

Your port still includes code.google.com/p/graphics-go/*, rather than referring to itself. This is mostly relevant because of the warning that we now get when we go get your package:

warning: code.google.com is shutting down; import path code.google.com/p/graphics-go/graphics/convolve will stop working

I would be happy to submit a pull request making your package self-referential, if there is interest.