biofriction-wp-theme/node_modules/is-jpg/readme.md

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# is-jpg [![Build Status](https://travis-ci.org/sindresorhus/is-jpg.svg?branch=master)](https://travis-ci.org/sindresorhus/is-jpg)
> Check if a Buffer/Uint8Array is a [JPEG](https://en.wikipedia.org/wiki/JPEG) image
## Install
```
$ npm install is-jpg
```
## Usage
##### Node.js
```js
const readChunk = require('read-chunk');
const isJpg = require('is-jpg');
const buffer = readChunk.sync('unicorn.jpg', 0, 3);
isJpg(buffer);
//=> true
```
##### Browser
```js
const xhr = new XMLHttpRequest();
xhr.open('GET', 'unicorn.jpg');
xhr.responseType = 'arraybuffer';
xhr.onload = () => {
isJpg(new Uint8Array(this.response));
//=> true
};
xhr.send();
```
## API
### isJpg(buffer)
Accepts a Buffer (Node.js) or Uint8Array.
It only needs the first 3 bytes.
## Related
- [file-type](https://github.com/sindresorhus/file-type) - Detect the file type of a Buffer/Uint8Array
## License
MIT © [Sindre Sorhus](https://sindresorhus.com)