heic-decode

Decode HEIC images to extract raw pixel data.

Install

1npm install @qs-coder/heic-decode

Usage

Decode the main image in the file:

1const fs = require('fs');
2const { promisify } = require('util');
3const decode = require('@qs-coder/heic-decode');
4
5(async () => {
6  const buffer = await promisify(fs.readFile)('/path/to/my/image.heic');
7  const {
8    width,  // integer width of the image
9    height, // integer height of the image
10    data    // Uint8ClampedArray containing pixel data
11  } = await decode({ buffer });
12})();

Decode all images in the file:

1const fs = require('fs');
2const { promisify } = require('util');
3const decode = require('@qs-coder/heic-decode');
4
5(async () => {
6  const buffer = await promisify(fs.readFile)('/path/to/my/multi-image.heic');
7  const images = await decode.all({ buffer });
8
9  for (let image of images) {
10    // decode and use each image individually
11    // so you don't run out of memory
12    const {
13      width,  // integer width of the image
14      height, // integer height of the image
15      data    // Uint8ClampedArray containing pixel data
16    } = await image.decode();
17  }
18})();

When the images are decoded, the return value is a plain object in the format of ImageData. You can use this object to integrate with other imaging libraries for processing.

Note that while the decoder returns a Promise, it does the majority of the work 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-convert - convert heic/heif images to jpeg and png
• libheif-js - libheif as a pure-javascript npm module