# Third-party software notices

## Historical staging HEIC decoder

A pre-release Open Canvas staging build briefly included `@discourse/heic`
1.0.0 from the
[discourse/jSquash project](https://github.com/discourse/jSquash/tree/345892e0e48b428d47875a5b5678fbcf58f2880e/packages/heic).
The current application does **not** ship that package or its Wasm decoder.
This notice and source offer remain available for recipients of the historical
staging build.

The package wrapper is Apache-2.0. Its `heic_dec.wasm` contained statically
linked copies of libheif 1.19.7 and libde265 1.0.15, covered by GNU LGPL version
3 or, at your option, any later version. You may modify those libraries and
reverse engineer that combined decoder for debugging such modifications. Full
license texts, exact corresponding source, and build/relink instructions are
available below.

### Components

- **jSquash HEIC wrapper / `@discourse/heic` 1.0.0** — Copyright 2023
  jamsinclair and contributors; Apache-2.0.
  [License](/third-party/licenses/jsquash-Apache-2.0.txt) ·
  [source](https://github.com/discourse/jSquash/tree/345892e0e48b428d47875a5b5678fbcf58f2880e/packages/heic)
- **libheif 1.19.7** (`c22636155fc6848b71ad77971159e6e1cc349cce`) —
  Copyright Dirk Farin and contributors; LGPL-3.0-or-later.
  [GPL/LGPL license text](/third-party/licenses/libheif-1.19.7-COPYING.txt) ·
  [source](https://github.com/strukturag/libheif/tree/v1.19.7)
- **libde265 1.0.15** (`17bb8d9fcea62db8cdeb0fc7ef8d15dbd19a22e4`) —
  Copyright struktur AG, Dirk Farin, Joachim Bauch, and contributors;
  LGPL-3.0-or-later.
  [GPL/LGPL license text](/third-party/licenses/libde265-1.0.15-COPYING.txt) ·
  [source](https://github.com/strukturag/libde265/tree/v1.0.15)
- **Emscripten 3.1.57 runtime material** — University of Illinois/NCSA and
  other permissive licenses.
  [License](/third-party/licenses/emscripten-3.1.57-LICENSE.txt)
- **musl libc material distributed with Emscripten** — Copyright contributors
  listed in the shipped notice; MIT and BSD-family terms.
  [Copyright and license notices](/third-party/licenses/musl-COPYRIGHT.txt)
- **LLVM libc++ runtime material linked by Emscripten 3.1.57** — Apache-2.0
  WITH LLVM-exception and the reproduced legacy notices.
  [License and notices](/third-party/licenses/llvm-libcxx-3.1.57-LICENSE.txt)
- **LLVM libc++abi runtime material linked by Emscripten 3.1.57** — Apache-2.0
  WITH LLVM-exception and the reproduced legacy notices.
  [License and notices](/third-party/licenses/llvm-libcxxabi-3.1.57-LICENSE.txt)
- **LLVM compiler-rt runtime material linked by Emscripten 3.1.57** —
  Apache-2.0 WITH LLVM-exception and the reproduced legacy notices.
  [License and notices](/third-party/licenses/llvm-compiler-rt-3.1.57-LICENSE.txt)

### Corresponding source and relinking

The owned source bundle contains the exact jSquash wrapper and build scripts,
pristine libheif and libde265 sources and checksums, identifies the pinned
Emscripten image by digest, and provides step-by-step rebuild/relink
instructions:

- [HEIC decoder 1.0.0 corresponding source](/third-party/sources/heic-decoder-1.0.0.tar.gz)
- Source archive SHA-256:
  `177558f51470950e95b846d5c7352de39e96afdfd9d8ef122800367a8c10f5bf`
- Historical `heic_dec.wasm` SHA-256:
  `832bfb37148038257e56216d165cfae24a8afaa7cae8fc0ddb1ef4bf495612a9`

The source archive is offered at no charge and will remain available for the
period required for recipients of the historical object code.