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Dropbox Open Sources New Lossless Middle-Out Image Compression Algorithm (dropbox.com)
Dropbox announced on Thursday that it is releasing its image compression algorithm dubbed Lepton under an Apache open-source license on GitHub. Lepton, the company writes, can both compress and decompress files, and for the latter, it can work while streaming. Lepton offers a 22% savings reductions for existing JPEG images, and preserves the original file bit-for-bit perfectly. It compresses JPEG files at a rate of 5MB/s and decodes them back to the original bit at 15MB/s. The company says it has used Lepton to encode 16 billion images saved to Dropbox, and continues to utilize the technology to recode its older images. You can find more technical details here.
Another fucking moron unable to read TFA!!!!!!!!!! Shoot yourself.
So you are an idiot. If you run a JPEG through Lepton the ORIGINAL file (from Lepton's point of view) is the JPEG. Not the Nikon raw file which it has now knowledge of.
This isn't a "better than JPEG" format. It's a "store existing JPEG files your users upload & use more efficiently" format. Flickr, for instance, could theoretically save 22% of its disk space using this.
It's not a file format, it's a compression algorithm that happens at the data storage level. This is similar to compressing a hard drive -- the files are individually compressed, but the file formats are the same, and the OS handles the compression/decompression seamlessly so that the applications don't even know they're accessing compressed versions of the file formats they normally use.
You can keep all your JPEGs, and with the open-source license, compress the contents of a drive or partition with this algorithm and save maybe 20% or so of the space the JPEG files took up. Not worth it for most people but photographers and image sites might save a lot of money using this.
Look, they clearly state that the operate at the level of JPEG-files. So, where is the confusion coming from? They are analyzing JPEG files and using features of that format to compress the already compressed files further.
Which I, honestly, find very impressive.
The reproduce JPEG files in a bit-by-bit faithful fashion. And the have tested in on 16 million (or was it billion) files where it worked without problems plus they don't replace user files unless they have checked that it decodes correctly. I presume that the process is actually transparent to the Dropbox user.
I don't see the problem that you have with this, sorry.
Good work lads!