SUMMARY
I’m recoding my TIFF files to JXL with Digikam. I want to do the same with my JPG files, however, before doing it, I have a question, related to re-encoding.

cjxl command line tool from libjxl let users to losslessly transcode JPEG images into JPEG XL. Transcoding preserves the already-lossy compression data from the original JPEG image without any quality loss caused by re-encoding, while making the file size smaller than the original, so my question is what library is using Digikam to transcode JPG to JXL?

Thank you