is-gif 
Check if a Buffer/Uint8Array is a GIF image
Install
$ npm install is-gif
Usage
const readChunk = require('read-chunk');
const isGif = require('is-gif');
const buffer = readChunk.sync('unicorn.gif', 0, 3);
isGif(buffer);
//=> true
API
isGif(input)
input
Type: Buffer Uint8Array
It only needs the first 3 bytes.
Related
- file-type - Detect the file type of a Buffer/Uint8Array
License
MIT © Sindre Sorhus