A Golang wrapper for libjxl.
On Windows, download the latest release of libjxl and extract the DLLs to the same directory as your application. You need all of them.
After building, the application might be statically linked? I'm not sure about that but it seems to be the case.
On Linux, install libbrotli-dev and, if your distro has it, libjxl-dev. (If not, get the package from the above link.)
This library registers itself with image and additionally exports Decode, DecodeConfig and Encode, which work as you might expect. For more complex usage, such as multi-frame JXLs, use the JxlEncoder and JxlDecoder objects.
Note that only Gray, RGBA, and NRGBA color models and their 16-bit counterparts are identitifed by the library.