dropbox / lepton

Lepton is a tool and file format for losslessly compressing JPEGs by an average of 22%.
https://blogs.dropbox.com/tech/2016/07/lepton-image-compression-saving-22-losslessly-from-images-at-15mbs/
Apache License 2.0
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What's the difference between lepton, lepton-avx, lepton-scalar and lepton-slow-best-ratio? #127

Closed stephane-archer closed 4 years ago

danielrh commented 4 years ago

lepton runs with default settings for the platform lepton-avx is compiled avx2 extensions and requires a compatible machine to run. It should be maginally faster on newer machines (eg if they don't downclock when using extended width vectors) lepton-scalar avoids vector instructions altogether (especially platforms like javascript that don't have vector instructions) lepton-slow-best-ratio defaults to single threaded behavior, allowing learned-buckets to be learned over the whole image rather than just a slice of it