offset number?

[zhuwanling]

why offset numbers are kW x kH x 2?
In the paper ,offset= 2 x N, the N is number of channel。

[LWJ312]

I don't think so. If you read paper again, you will find

'In deformable convolution, the regular grid R is augmented with offsets{∆pn|n = 1,...,N}, where N = |R|. '