How to translate flow to coordinate?

[Devlee247]

Thanks for your nice work!

I'm curious about how to translate flow to coordinate. (u,v -> x, y)

[ksimmo]

If you mean target coordinates (x,y) then it is quite simple. Just take the starting position of that pixel and add the flow vector of that pixel to get the target coordinates:

#assuming flow has the shape BxCxHxW

yy,xx = torch.meshgrid(torch.arange(flow.size(-2)), torch.arange(flow.size(-1)), indexing="ij") 
spatial_pos = torch.stack([xx,yy], dim=0)
target_pos = spatial_pos.unsqueeze(0)+flow