C4ID

A JavaScript module for NodeJS to generate C4 IDs. Written in TypeScript. As described in SMPTE ST 2114:2017, a C4 ID is a 90 character Base58 string representation of a SHA512 hash. This package does not create SHA512 hashes, it simply creates their C4 ID representation.

Installing / Getting started

$ npm install --save c4id

import { createHash } from 'node:crypto';
import C4ID from 'c4id';

const digest = createHash('sha512').update('alfa').digest();
const c4 = C4ID.fromSHA512Hash(digest);

console.log(c4); //c43zYcLni5LF9rR4Lg4B8h3Jp8SBwjcnyyeh4bc6gTPHndKuKdjUWx1kJPYhZxYt3zV6tQXpDs2shPsPYjgG81wZM1

Developing

Built With

This package was built and tested on Node.js 16.20.2.

The only development dependencies Typescript and packages needed for testing and linting, i.e. Mocha and ESLint, plus plugins for both.

Setting up Dev

git clone https://github.com/bradcordeiro/c4id
cd c4id
npm install

Versioning

This package uses Semantic Versioning.

Tests

SMPTE ST 2114:2017 includes test cases in Appendix B, and those test cases are implemented in this package using Mocha.

npm test

To run the tests using Mocha.

Style guide

This package was written using the Airbnb Style Guide. A .eslintrc file is included in source control, and ESLint as well as the Airbnb plugin are included as development dependencies.

API Reference

Functions

Function	Argument Type	Return Type	Description
fromSHA512Hash(sha512Hash)	UInt8Array	string	Takes a SHA512 hash and returns a C4 ID string.
toSHA512Digest(c4id)	string	UInt8Array	Takes a C4 ID and returns a SHA512 hash digest.
fromIds(c4ids)	string[]	string	SMPTE ST 2114:2017 describes a method to generate a C4 ID from other C4 IDs (e.g. to generate a single C4 ID from multiple files in the same folder). This function will take an array of C4 IDs and return a single C4 ID from the input, as specified in SMPTE ST 2114:2017.

Licensing

Released under the MIT License.