heic-to

Convert HEIC/HEIF images to JPEG, PNG in browser using Javascript.

Inspired by heic2any and libheif-web. The purpose of heic-to is to continuously follow up on releases of libheif to be able to preview HEIC/HEIF images in browser.

Currently, heic-to is using libheif 1.19.7 under the hood.

| Release | libheif | | -------- | -------- | | 1.1.11 | 1.19.7 | | 1.1.10 | 1.19.7 | | 1.1.9 | 1.19.7 | | 1.1.8 | 1.19.7 | | 1.1.7 | 1.19.6 | | 1.1.6 | 1.19.5 | | 1.1.5 | 1.19.5 | | 1.1.4 | 1.19.4 | | 1.1.3 | 1.19.3 | | 1.1.2 | 1.19.2 | | 1.1.1 | 1.19.1 | | 1.1.0 | 1.19.0 | | 1.0.3 | 1.18.2 | | 1.0.2 | 1.18.2 | | 1.0.1 | 1.18.2 | | 1.0.0 | 1.18.1 |

Usage

Check whether the image is HEIC or not

import { isHeic } from "heic-to"

const file = field.files[0]
await isHeic(file)

Convert HEIC to JPEG/PNG

import { heicTo } from "heic-to"

const file = field.files[0]

const jpeg = await heicTo({
  blob: file,
  type: "image/jpeg",
  quality: 0.5
})

const png = await heicTo({
  blob: file,
  type: "image/png",
  quality: 0.5
})

Cotent Security Policy

When meets CSP issue like this:

Refused to evaluate a string as JavaScript because 'unsafe-eval' is not an allowed source of script in the following Content Security Policy directive

Fix it by using csp/heic-to

- import { heicTo } from "heic-to"
+ import { heicTo } from "heic-to/csp"

Development guide

How to fast test your changes on local?

yarn s

This will open http://127.0.0.1:8080/example/ for easy testing.

How to build libheif.js from libheif on Mac

brew install cmake make pkg-config x265 libde265 libjpeg libtool
brew install emscripten

git clone git@github.com:strukturag/libheif.git

Did below changes from build-emscripten.sh

# EXPORTED_FUNCTIONS=$($EMSDK/upstream/bin/llvm-nm $LIBHEIFA --format=just-symbols | grep "^heif_\|^de265_\|^aom_" | grep "[^:]$" | sed 's/^/_/' | paste -sd "," -)
EXPORTED_FUNCTIONS=$(/opt/homebrew/opt/llvm/bin/llvm-nm $LIBHEIFA --format=just-symbols | grep "^heif_\|^de265_\|^aom_" | grep "[^:]$" | sed 's/^/_/' | paste -sd "," -)

Start building

cd libheif
mkdir buildjs
cd buildjs
USE_WASM=0 ../build-emscripten.sh ..

# Or build without unsafe-eval
USE_UNSAFE_EVAL=0 USE_WASM=0 ../build-emscripten.sh ..