Hello, I am trying to compute key images. I am almost there, but I am probable doing something wrong when compressing coordinates. I described my problem here and I would be very happy if somebody could help me a bit with this: pastebin.com/LwzqfGCq

*probably

When computing a key image = x*H_p(P), what determines which coordinate (y-pos or y-neg) I take as a key image?

i_a how are you compressing P and why is I different