Open-source software
Handover's website turns iPhone photos into JPEGs in your browser. It uses three open-source parts to do that. They are not Handover's own code. They come under the GNU Lesser General Public License, version 3. Handover's own code is not under that licence.
The three parts
heic-to 1.6.5
Turns the HEIC photo into a JPEG in your browser.
Copyright Its licence file carries no copyright line. The author named in the package is Hopper Gee.
Licence LGPL-3.0
Source heic-to 1.6.5 from the project · Handover's own copy (6.3 MB)
libheif 1.23.5
Reads the HEIC file. heic-to is built on it.
Copyright As its source files write it: Copyright (c) 2017-2025 Dirk Farin <dirk.farin@gmail.com>. In some files: Copyright (c) 2017 struktur AG, Joachim Bauch <bauch@struktur.de>.
Licence LGPL-3.0
Source libheif 1.23.5 from the project · Handover's own copy (2.3 MB)
libde265 1.0.16
Decodes the picture inside the HEIC file. libheif is built on it.
Copyright As its source files write it: Copyright (c) 2013-2014 struktur AG, Dirk Farin <farin@struktur.de>.
Licence LGPL-3.0
Source libde265 1.0.16 from the project · Handover's own copy (0.8 MB)
Licence texts
The full texts, served by Handover. The Lesser licence builds on the General Public License, so both are here.
Using your own copy
Your browser loads the converter unchanged from /api/heic-converter?v=1.6.5 as a JavaScript module. Handover uses only its heicTo function. You can replace that file with your own build of heic-to that offers the same function, for example with your browser's local override, and Handover will use it.
To check that the file is the upstream one, compare its SHA-256 with this. It is dist/csp/heic-to.js from heic-to 1.6.5.
7b5a085d33318ab708c7d70f753b1aec9068004c77b2c3f360b426bfb793b8b6