What are the co-ordinates of generator G in his uncompressed form on secp256k1?

Question

I was looking at BitcoinWiki and it says that G, in it's uncompressed form, has a value of:
G = 04 79BE667E F9DCBBAC 55A06295 CE870B07 029BFCDB 2DCE28D9 59F2815B 16F81798 483ADA77 26A3C465 5DA4FBFC 0E1108A8 FD17B448 A6855419 9C47D08F FB10D4B8
Since it's uncompressed, it should contain information about X, but Y as well. How can I determinate those co-ordinates out of this?
Thank you!

score 6 · Accepted Answer · answered Aug 16 '20 at 14:50

6

The 04 first byte header indicates this is an uncompressed point (02 indicates compressed).

From there, it is simply an x followed by y representation - The first 32 bytes are x, the following 32 bytes are y. Therefore,

x = 79BE667E F9DCBBAC 55A06295 CE870B07 029BFCDB 2DCE28D9 59F2815B 16F81798
y = 483ADA77 26A3C465 5DA4FBFC 0E1108A8 FD17B448 A6855419 9C47D08F FB10D4B8

More details on how compact elliptic point representations work can be found in this spec.

answered Aug 16 '20 at 14:50

Raghav Sood

17,027
3
22
43

1

(For the sake of completeness) Both 2 and 3 indicate compressed form. – Coding Enthusiast Aug 17 '20 at 05:19
Correct, details on the encoding can be found in the very short and digestable SEC-1: https://www.secg.org/SEC1-Ver-1.0.pdf – Raghav Sood Aug 17 '20 at 07:18

What are the co-ordinates of generator G in his uncompressed form on secp256k1?

1 Answers1