How to understand these parameters in "shift-convolution"?

[stidk]

self.weight[0g:1g, 0, 1, 2] = 1.0 ## left self.weight[1g:2g, 0, 1, 0] = 1.0 ## right self.weight[2g:3g, 0, 2, 1] = 1.0 ## up self.weight[3g:4g, 0, 0, 1] = 1.0 ## down self.weight[4*g:, 0, 1, 1] = 1.0 ## identity

i think [1,2] is down,[1,0] is up,[2,1] is right,[0,1] is left.