@juhasztibi/browser-image-resizer v2.2.1

browser-image-resizer

Introduction

This library allows for cross-browser image downscaling and resizing utilizing <canvas>. The code was part of Ross Turner's HTML5-ImageUploader. Note that this is meant to be a browser-only utility and will not work in Node.js.

Demo

• Code Sandbox - NPM
• Code Sandbox - In-Browser

Installation

NPM/Yarn

• npm install browser-image-resizer
• yarn add browser-image-resizer

Browser

<script src="https://cdn.jsdelivr.net/gh/ericnograles/browser-image-resizer@2.2.0/dist/index.js"></script>

Usage

NPM/Yarn

Promises

import { readAndCompressImage } from 'browser-image-resizer';

const config = {
  quality: 0.5,
  maxWidth: 800,
  maxHeight: 600,
  autoRotate: true,
  debug: true
};

// Note: A single file comes from event.target.files on <input>
readAndCompressImage(file, config)
  .then(resizedImage => {
    // Upload file to some Web API
    const url = `http://localhost:3001/upload`;
    const formData = new FormData();
    formData.append('images', resizedImage);
    const options = {
      method: 'POST',
      body: formData
    };

    return fetch(url, options);
  })
  .then(result => {
    // TODO: Handle the result
    console.log(result);
  });

Async/Await

import { readAndCompressImage } from 'browser-image-resizer';

const config = {
  quality: 0.7,
  width: 800,
  height: 600
};

// Note: A single file comes from event.target.files on <input>
async function uploadImage(file) {
  try {
    let resizedImage = await readAndCompressImage(file, config);

    const url = `http://localhost:3001/upload`;
    const formData = new FormData();
    formData.append('images', resizedImage);
    const options = {
      method: 'POST',
      body: formData
    };

    let result = await fetch(url, options);

    // TODO: Handle the result
    console.log(result);
    return result;
  } catch (error) {
    console.error(error);
    throw(error);
  }
}

Browser

Promises

const config = {
  quality: 0.5,
  maxWidth: 800,
  maxHeight: 600,
  autoRotate: true,
  debug: true
};

// Note: A single file comes from event.target.files on <input>
BrowserImageResizer.readAndCompressImage(file, config)
  .then(resizedImage => {
    // Upload file to some Web API
    const url = `http://localhost:3001/upload`;
    const formData = new FormData();
    formData.append('images', resizedImage);
    const options = {
      method: 'POST',
      body: formData
    };

    return fetch(url, options);
  })
  .then(result => {
    // TODO: Handle the result
    console.log(result);
  });

Async/Await

const config = {
  quality: 0.7,
  width: 800,
  height: 600
};

// Note: A single file comes from event.target.files on <input>
async function uploadImage(file) {
  try {
    let resizedImage = await BrowserImageResizer.readAndCompressImage(file, config);

    const url = `http://localhost:3001/upload`;
    const formData = new FormData();
    formData.append('images', resizedImage);
    const options = {
      method: 'POST',
      body: formData
    };

    let result = await fetch(url, options);

    // TODO: Handle the result
    console.log(result);
    return result;
  } catch (error) {
    console.error(error);
    throw(error);
  }
}

readAndCompressImage(file, config) => Promise

Inputs

• file: A File object, usually from an <input>
• config: See below

Outputs

A Promise that yields an Image Blob

Known Issues

EXIF Data in iOS

When using a specific camera setting in iOS, EXIF data gets stripped by default: https://stackoverflow.com/questions/57942150/file-upload-and-exif-in-mobile-safari

In order for this to work, a user will need to change their iOS camera settings to "Most Compatible" as below: