meta-png

!Test
!Lint

Simple, zero-dependencies NodeJS/JavaScript library to store and retrieve metadata in PNG files.

Installation

Use your favourite package manager
``bash
npm install meta-png

or: yarn add meta-png

`

Usage

The library provides two functions to add a new metadata:

`javascript
addMetadata(PNGUint8Array, key, value) // stores the given key-value inside the PNG, provided as Uint8Array
addMetadataFromBase64DataURI(dataURI, key, value) // stores the given key-value inside the PNG, provided as a Data URL string
`

and a function to get back the stored value:

`javascript
getMetadata(PNGUint8Array, key) // retrives the given key from a PNG provided as Uint8Array
`

Limitations


- tEXt chunks inside PNG files are meant to use the Latin-1 standard: using characters outside this charset may lead to unwanted behaviors
- No check is performed inside add functions to test whether a given key is already present in the file. If you need it, you can call getMetadata beforehand and assert that it gives back undefined`.