Donaldcwl
Browser Image Compression
Javascript module to be run in the web browser for image compression.
Features
- You can use this module to compress jpeg and png image by reducing resolution or storage size before uploading to application server to save bandwidth.
- Multi-thread (web worker) non-blocking compression are supported through options.
Install
You can download imageCompression from the dist folder. Alternatively, you can install it via yarn or npm
npm install browser-image-compression --save
or
yarn add browser-image-compressionor use a CDN like delivrjs:
https://cdn.jsdelivr.net/npm/browser-image-compression@1.0.13/dist/browser-image-compression.js
or
https://cdn.jsdelivr.net/npm/browser-image-compression@latest/dist/browser-image-compression.jsHow to use this module in your project?
Use as ES module
(can be used in framework like React, Angular, Vue etc)
(work with bundler like webpack and rollup)
import imageCompression from 'browser-image-compression';or
In html file
<script type="text/javascript" src="https://cdn.jsdelivr.net/npm/browser-image-compression@1.0.13/dist/browser-image-compression.js"></script>API
Main function
// you should provide one of maxSizeMB, maxWidthOrHeight in the options
const options = {
maxSizeMB: number, // (default: Number.POSITIVE_INFINITY)
maxWidthOrHeight: number, // compressedFile will scale down by ratio to a point that width or height is smaller than maxWidthOrHeight (default: undefined)
onProgress: Function, // optional, a function takes one progress argument (percentage from 0 to 100)
useWebWorker: boolean, // optional, use multi-thread web worker, fallback to run in main-thread (default: true)
// following options are for advanced users
maxIteration: number, // optional, max number of iteration to compress the image (default: 10)
exifOrientation: number, // optional, see https://stackoverflow.com/a/32490603/10395024
fileType: string, // optional, fileType override
initialQuality: number // optional, initial quality value between 0 and 1 (default: 1)
}
imageCompression(file: File, options): Promise<File>Helper function
- for advanced users only, most users won't need to use the helper functions
imageCompression.getDataUrlFromFile(file: File): Promise<base64 encoded string> imageCompression.getFilefromDataUrl(dataUrl: string, filename: string, lastModified?: number): Promise<File> imageCompression.loadImage(url: string): Promise<HTMLImageElement> imageCompression.drawImageInCanvas(img: HTMLImageElement): HTMLCanvasElement | OffscreenCanvas imageCompression.drawFileInCanvas(file: File): Promise<[ImageBitmap | HTMLImageElement, HTMLCanvasElement | OffscreenCanvas]> imageCompression.canvasToFile(canvas: HTMLCanvasElement | OffscreenCanvas, fileType: string, fileName: string, fileLastModified: number, quality?: number): Promise<File> imageCompression.getExifOrientation(file: File): Promise<number> // based on https://stackoverflow.com/a/32490603/10395024
Usage
<input type="file" accept="image/*" onchange="handleImageUpload(event);">async await syntax:
async function handleImageUpload(event) {
const imageFile = event.target.files[0];
console.log('originalFile instanceof Blob', imageFile instanceof Blob); // true
console.log(`originalFile size ${imageFile.size / 1024 / 1024} MB`);
const options = {
maxSizeMB: 1,
maxWidthOrHeight: 1920,
useWebWorker: true
}
try {
const compressedFile = await imageCompression(imageFile, options);
console.log('compressedFile instanceof Blob', compressedFile instanceof Blob); // true
console.log(`compressedFile size ${compressedFile.size / 1024 / 1024} MB`); // smaller than maxSizeMB
await uploadToServer(compressedFile); // write your own logic
} catch (error) {
console.log(error);
}
}Promise.then().catch() syntax:
function handleImageUpload(event) {
var imageFile = event.target.files[0];
console.log('originalFile instanceof Blob', imageFile instanceof Blob); // true
console.log(`originalFile size ${imageFile.size / 1024 / 1024} MB`);
var options = {
maxSizeMB: 1,
maxWidthOrHeight: 1920,
useWebWorker: true
}
imageCompression(imageFile, options)
.then(function (compressedFile) {
console.log('compressedFile instanceof Blob', compressedFile instanceof Blob); // true
console.log(`compressedFile size ${compressedFile.size / 1024 / 1024} MB`); // smaller than maxSizeMB
return uploadToServer(compressedFile); // write your own logic
})
.catch(function (error) {
console.log(error.message);
});
}Demo / Example
open https://donaldcwl.github.io/browser-image-compression/example/basic.html
or check the "example" folder in this repo
Browsers support
 IE / Edge |
 Firefox |
 Chrome |
 Safari |
 Opera |
 Chrome for Android |
|---|---|---|---|---|---|
| IE10, IE11, Edge | last 2 versions | last 2 versions | last 2 versions | last 2 versions | last 2 versions |
IE support
Promise API is being used in this library. If you need to support browser that do not support Promise like IE. You can include the Promise polyfill in your project.
See: https://github.com/taylorhakes/promise-polyfill
You can include the following script to load the Promise polyfill:
<script src="https://cdn.jsdelivr.net/npm/promise-polyfill@8/dist/polyfill.min.js"></script>Typescript type definitions
Typescript definitions are included in the package & referenced in the types section of the package.json
Contribution
- fork the repo and git clone it
- run
npm run watch# it will watch code change in lib/ folder and generate js in dist/ folder - add/update code in lib/ folder
- try the code by opening example/development.html which will load the js in dist/ folder
- add/update test in test/ folder
npm run test- push to your forked repo on github
- make a pull request to this repo