heic-convert

Convert HEIC/HEIF images to JPEG and PNG

Install

npm install heic-convert

Usage

Convert the main image in a HEIC to JPEG

const { promisify } = require('util');
const fs = require('fs');
const convert = require('heic-convert');

(async () => {
  const inputBuffer = await promisify(fs.readFile)('/path/to/my/image.heic');
  const outputBuffer = await convert({
    buffer: inputBuffer, // the HEIC file buffer
    format: 'JPEG',      // output format
    quality: 1           // the jpeg compression quality, between 0 and 1
  });

  await promisify(fs.writeFile)('./result.jpg', outputBuffer);
})();

Convert the main image in a HEIC to PNG

const { promisify } = require('util');
const fs = require('fs');
const convert = require('heic-convert');

(async () => {
  const inputBuffer = await promisify(fs.readFile)('/path/to/my/image.heic');
  const outputBuffer = await convert({
    buffer: inputBuffer, // the HEIC file buffer
    format: 'PNG'        // output format
  });

  await promisify(fs.writeFile)('./result.png', outputBuffer);
})();

Convert all images in a HEIC

const { promisify } = require('util');
const fs = require('fs');
const convert = require('heic-convert');

(async () => {
  const inputBuffer = await promisify(fs.readFile)('/path/to/my/image.heic');
  const images = await convert.all({
    buffer: inputBuffer, // the HEIC file buffer
    format: 'JPEG'       // output format
  });

  for (let idx in images) {
    const image = images[idx];
    const outputBuffer = await image.convert();
    await promisify(fs.writeFile)(`./result-${idx}.jpg`, outputBuffer);
  }
})();

The work to convert an image is done when calling image.convert(), so if you only need one of the images in a multi-image file, you can convert just that one from the images array and skip doing any work for the remaining images.

Note that while the converter returns a Promise and is overall asynchronous, a lot of work is still done synchronously, so you should consider using a worker thread in order to not block the main thread in highly concurrent production environments.

Related

• heic-cli - convert heic/heif images to jpeg or png from the command line
• heic-decode - decode heic images to raw image data
• libheif-js - libheif as a pure-javascript npm module