sindresorhus / image-type

Detect the image type of a Buffer/Uint8Array

image-type

Detect the image type of a Buffer/Uint8Array

See the file-type module for more file types and a CLI.

Install

npm install image-type

Usage

Node.js

import {readChunk} from 'read-chunk';
import imageType, {minimumBytes} from 'image-type';

const buffer = await readChunk('unicorn.png', {length: minimumBytes});

await imageType(buffer);
//=> {ext: 'png', mime: 'image/png'}

Or from a remote location:

import https from 'node:https';
import imageType, {minimumBytes} from 'image-type';

const url = 'https://upload.wikimedia.org/wikipedia/en/a/a9/Example.jpg';

https.get(url, response => {
	response.on('readable', () => {
		(async () => {
			const chunk = response.read(minimumBytes);
			response.destroy();
			console.log(await imageType(chunk));
			//=> {ext: 'jpg', mime: 'image/jpeg'}
		})();
	});
});

Browser

const xhr = new XMLHttpRequest();
xhr.open('GET', 'unicorn.png');
xhr.responseType = 'arraybuffer';

xhr.onload = () => {
	(async () => {
		await imageType(new Uint8Array(this.response));
		//=> {ext: 'png', mime: 'image/png'}
	})();
};

xhr.send();

API

imageType(input)

Returns an Promise<object> with:

• ext - One of the supported file types
• mime - The MIME type

Or undefined when there is no match.

input

Type: Buffer | Uint8Array

It only needs the first minimumBytes amount of bytes.

minimumBytes

Type: number

The minimum amount of bytes needed to detect a file type. Currently, it's 4100 bytes, but it can change, so don't hardcode it.

Supported file types

• jpg
• png
• gif
• webp
• flif
• cr2
• tif
• bmp
• jxr
• psd
• ico
• bpg
• jp2 - JPEG 2000
• jpm - JPEG 2000
• jpx - JPEG 2000
• heic
• cur
• dcm - DICOM Image File

SVG isn't included as it requires the whole file to be read, but you can get it here.

Related

• file-type - Detect the type of a file
• image-dimensions - Get the dimensions of an image

image-type's Issues

Returning null when the buffer from a particular image link is used to get image type

Hi, when I make a HTTP GET request to this link https://cdn-sliders.eneba.com/QzxlwqBtARNYe7vb3hFE8XiV5NgPrtNcLGT7ZV2bAIU.jpeg and get its response as buffer and try to do imageType(buffer), it's returning null, I don't get why this happens, I've also checked a few images from that website (like 3) whose link is from cdn-sliders.eneba.com, all of their buffer is present but somehow, imageType(buffer) is always returning null for all of those links, I don't understand why this happens to these links from that website.

I've tested the same image in Discord's CDN by uploading it into Discord which gave me the link https://cdn.discordapp.com/attachments/764486125338230834/837739672654446622/QzxlwqBtARNYe7vb3hFE8XiV5NgPrtNcLGT7ZV2bAIU.jpeg which works totally fine and I was able to get the output successfully but getting null when I use the original link from that website, is there any reason behind this that anyone know of?

Detect From Remote URL

Hi, how to able read image-type from given URL?

Thanks

jpg => jpeg

Same as #6

SVG image is recognized as XML and thus is not considered "an image"

The library could've done something custom for SVGs (since it's anyway coupled to the images), like detecting an <svg> tag inside the file content or so.

Update file-type dependency to 16.5.4 for [email protected]

We are using [email protected] (i.e. not 5.x) because we can not use an ESM module. However, [email protected] has a dependency on [email protected], which has a reported vulnerability.

Could we get an [email protected] with an updated dependency on [email protected], so we can keep using image-type pre-ESM? Thanks!

AVIF codec missing

The library doesn't support AVIF codec. Can you please add it?

Update file-type dependency

This package depends on file-type v10 which is already a few major versions behind and marked as vulnerable by snyk. Note that I didn't verify if the vulnerability would really be a problem in reality. An update to the newest major version would still be nice though.

This package is e.g. used by image-js.

Document what happens when the buffer isn't an image

It would be good to add to the documentation that null is returned when an image format can't be found.

tif => tiff

The mime package per https://github.com/broofa/node-mime/blob/master/types/mime.types#L1330 will return tiff as opposed to tif like you have here via image-type. Can you swap it to "tiff" instead? Or what is your argument for "tif" and not being consistent with mime's mime.lookup?

Issue with image links that are having GET methods in the url bar

So let's say I have this piece of code

And then send the next URL image to the Node Js server to check it's mime type
https://static.independent.co.uk/s3fs-public/thumbnails/image/2017/09/12/11/naturo-monkey-selfie.jpg?w968h681

Bug: The function is returning null because of the "?w968h681" part of the url which is a GET request to resize the image.
When I remove that GET request the mime type is returned with no problems at all.

Some files fail the check

I have been using image-type for a while with great success. However, today I spotted that some files do not pass the check. Like this one

I have downloaded it and run in node repl:

> let rawImage
> let imageType
> const downloadImgBuffer = url => fetch(url).then(res => res.arrayBuffer()).then(data => Buffer.from(data)).then(image => { rawImage = image })
> import('image-type').then(m => { imgType = m.default })
> downloadImgBuffer('https://www.propertyfinder.ae/property/ff905549921f7bf7290837418d80b1cb/1312/894/MODE/588a2a/9568812-c8c42o.jpg?ctr=ae)
> imgType(rawImage).then(res => console.log(`this is the res: "${JSON.stringify(res)}"`))
this is the res: "false"

Exactly the same code with other images works just fine, ie this image correctly prints this is the res: "{"ext":"jpg","mime":"image/jpeg"}".

Checking on another website that gives image type, extension, mime etc: https://www.checkfiletype.com/ and dragging over there the failing image above gives correct image type:

File Type: image data, standard 1.01, aspect ratio, density 1x1, segment length 16, baseline, precision 8, 1312x894, frames 3
MIME Type: image/jpeg;
Suggested file extension(s): jpg jpeg jpe jfif

Furthermore, according to documentation the imageType function is supposed to return undefined if it fails to establish image type, but by the looks of the above it returns false.