Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Lepton image compression: saving 22% losslessly from images at 15MB/s

blogs.dropbox.com

Post reply on HN
Print view View original

91–100 of 196 posts

Re: Lepton image compression: saving 22% losslessly from images at 15MB/s

#91

Post by orware »

Are we able to take the EXE and run it on JPEGs from a Windows machine without issue? (I haven't tried it myself, but probably will using the instructions I saw on Github a moment ago and report back...it looks like it should work though): https://github.com/dropbox/lepton/releases

However I am wondering about the two different EXEs available on the page (one has an avx prefix that I need to try and figure out). If anyone has info on that that'd be useful.

I could see this potentially being useful for schools and businesses doing quite a bit of digital scanning so I'm going to try running some tests using it and some images I think we have available somewhere.

Re: Lepton image compression: saving 22% losslessly from images at 15MB/s

#93

Post by Apofis »

ausjke wrote: post #21

This is very impressive for archiving images. For a quick test, I run it over ~1.3GB JPEG pictures I had locally, the finally result is 810M, that's 66% of the original size, very impressive considering it's lossless. It only deals with jpg file though, no png, no iso, no zip, no any formats other than JPG. If someone can do this over video files that will be PiedPiper comes into real life.

It seems like the real bottleneck here is binary... why can we not start supporting base 10 yet? Or even base 64? a-Z+0-9?

Re: Lepton image compression: saving 22% losslessly from images at 15MB/s

#94

Post by mappu »

orware wrote: post #91

Are we able to take the EXE and run it on JPEGs from a Windows machine without issue? (I haven't tried it myself, but probably will using the instructions I saw on Github a moment ago and report back...it looks like it should work though): https://github.com/dropbox/lepton/releases However I am wondering about the two different EXEs available on the page (one has an avx prefix that I need to try and figure out). If a…

It should work fine.

The AVX version will be faster, but it requires a recent-ish CPU: https://en.wikipedia.org/wiki/Advanced_Vector_Extensions#CPU...

Re: Lepton image compression: saving 22% losslessly from images at 15MB/s

#95

Post by mcbits »

sevenless wrote: post #82

I'm interested in a 'super lossy' (deep learning based?) compression. You should be able to compress movies down to a screenplay and a few stage directions. A picture should of course be worth 1000 words.

I started something like this long ago but didn't get very far with it. This was before "deep learning" and I was groping in the dark, but I think the concept is sound up to a point.

The idea was to train a neural net and build up a database of features (maybe on the order of 1-10 GB, or whatever is just small enough to ship) to estimate the missing details from downscaled and extremely over-compressed JPEGs. If it worked, I think it would also improve the quality of all the 10-20 year old images out there where the uncompressed source is long gone. Sort of a Blade Runner-style "enhance" tool, but of course it would only be filling in aesthetically plausible details.

Re: Lepton image compression: saving 22% losslessly from images at 15MB/s

#97

Post by orware »

mappu wrote: post #94
orware wrote: post #91

Are we able to take the EXE and run it on JPEGs from a Windows machine without issue? (I haven't tried it myself, but probably will using the instructions I saw on Github a moment ago and report back...it looks like it should work though): https://github.com/dropbox/lepton/releases However I am wondering about the two different EXEs available on the page (one has an avx prefix that I need to try and figure out). If a…

It should work fine. The AVX version will be faster, but it requires a recent-ish CPU: https://en.wikipedia.org/wiki/Advanced_Vector_Extensions#CPU...

Thank you very much for the extra details mappu! That answers my question :-).

Re: Lepton image compression: saving 22% losslessly from images at 15MB/s

#99

Post by wongarsu »

ValentineC wrote: post #96

Would someone be kind enough to explain how one could store the compressed .lep files, serve them, and then have the browser render them, without using a JavaScript library?

You would either need a JavaScript library (which doesn't exist yet) or you would need to convince browser vendors to support lepton files natively.

In Dropbox's case they control both client and server and can just compress/decompress in the dropbox client. Using lepton on websites wasn't really Dropbox's goal (but it would be cool if a sufficiently fast JavaScript library existed).

Post reply on HN