'How get btc address from public key in node js

I apologize for my English!

How decode hex public key from BTC signature script to string address in node js?

For example I have the follow hex public key:

03745AAAF364030720B2D14DE50A3310EEF521C91E36353DCA20813713535C005A

after decoding I should get corresponding bitcoin address as

1GNXpcYzasmmXvM4rNgkvZ5SzXgL4L9Ch6

In https://bitcoin.stackexchange.com/questions/71867/decoding-scriptsig was question about decoding ScriptSig of btc transactions and there was the follow fragment:

...
21: OP_DATA_0x21:        compressed pub key (33 Bytes)
    03745AAAF3640307:20B2D14DE50A3310:EEF521C91E36353D:CA20813713535C00:5A
    This is MultiSig's compressed Public Key (X9.63 form)
    corresponding bitcoin address is:    1GNXpcYzasmmXvM4rNgkvZ5SzXgL4L9Ch6
...

In accordance with this question btc public key is encoded in ANSI X9.63 format.

Do nodejs have ways to decode ANSI X9.63 format?

Thank you very much!

node.jsbitcoinansi


Solution 1:[1]

You must have node and npm downloaded on your computer.

npm install bitcoinjs-lib

Download bitcoinjs library from your node terminal.

var bitcoin = require("bitcoinjs-lib")

Require bitcoinjs-lib.

var keyPair = bitcoin.ECPair.makeRandom(); or var keyPair = "03745AAAF364030720B2D14DE50A3310EEF521C91E36353DCA20813713535C005A"

Make variable for keyPair.

console.log(keyPair.getAddress());

Test address by logging address to console. A valid bitcoin address should be returned.

var address = keyPair.getAddress();

Save bitcoin address result to a variable.

console.log(keyPair.toWif());

Test private key by logging to console. A valid bitcoin private key should be returned.

var pkey = keyPair.toWIF();

Save bitcoin private key result to a variable.

Solution 2:[2]

Bitcoin uses "Elliptic Curve Digital Signature Algorithm", therefore I use https://www.npmjs.com/package/elliptic

import EC from "elliptic";

// use a prime number to generate the curve. that p i 256 bits.
//  ec works better with hashed values. we always hash the data.
const ec = new EC.ec("secp256k1");

create public key

const keyPair = ec.genKeyPair();
// ec returns x,y points of elliptic curve. so we convert it to hex.
const publicKey = keyPair.getPublic().encode("hex");

Sources

This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.

Source: Stack Overflow

Solution Source
Solution 1 Putti
Solution 2 Yilmaz

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