1.2.1 • Published 6 years ago

browser-image-resizer-rotate v1.2.1

Weekly downloads
7
License
MIT
Repository
github
Last release
6 years ago

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. Adapted from original work to allow manyally setting the exif-orientation for rotation and flipping purposes.

Demo

https://browser-image-resizer-test.firebaseapp.com/

Installation

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

Sample - 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);
  });

Sample - 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);
  }
}

readAndCompressImage(file, config) => Promise

Inputs

  • file: A File object, usually from an <input>
  • config: See below
Property NamePurposeDefault Value
qualityThe quality of the JPEG0.5
maxWidthThe maximum width for the downscaled image800
maxHeightThe maximum height for the downscaled image600
autoRotateReads EXIF data on the image to determine orientationtrue
exifOrientationManually sets EXIF orientation value. Only works if autoRotate is false0
debugconsole.log image update operationsfalse

Outputs

A Promise that yields a JPEG Blob