Brunsli cannot decode JPEG that was compressed in JPEG XL's reference software's unofficial build about brunsli

[eustas]

JPEG XL specification is an umbrella for several codecs and "containers".
"Brunsli" is just one on codecs. That is why it can not decode all the JPEG XL files.

Quality degradation is something new. Going to investigate that on the next week.

[eustas]

Just checked with freshly build binaries on OSX: indeed, --jpeg option causes degradation. I believe it is misleading; at least it should have better explanation what is does.
Currently there is no way to ask JXL CLI to restore original JPEG. There is, though, a "to-do" to add that ability.

BTW: one of JPEG XL CLI tools - cbrunsli - could be used to produce files compatible with https://brunsli.dev page. Unfortunately it is not included in Jamaicas build.

[Mithgol]

Brunsli encoder has a separate CLI and Brunsli decoder is not (yet) included in JXL CLI.

It makes sense, and thus the issue's closed.