"LMCompress is a compression algorithm using large models (large language model for texts, large image model for images, etc.).

Google has developed and open-sourced a new JPEG algorithm that reduces file size by about 35 percent—or alternatively, image quality can be significantly improved while keeping file size constant.

As well as LZMA, you can opt to use the LZO algorithms, which are insanely fast, but don't provide a great compression ratio, or the glacially slow ZPAQ, which gives maximum compression ratios.