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Google Publishes Zopfli, an Open-Source Compression Library
alphadogg writes "Google is open-sourcing a new general purpose data compression library called Zopfli that can be used to speed up Web downloads. The Zopfli Compression Algorithm, which got its name from a Swiss bread recipe, is an implementation of the Deflate compression algorithm that creates a smaller output size (PDF) compared to previous techniques, wrote Lode Vandevenne, a software engineer with Google's Compression Team, on the Google Open Source Blog on Thursday. 'The smaller compressed size allows for better space utilization, faster data transmission, and lower Web page load latencies. Furthermore, the smaller compressed size has additional benefits in mobile use, such as lower data transfer fees and reduced battery use,' Vandevenne wrote. The more exhaustive compression techniques achieve higher data density, but also make the compression a lot slower. This does not affect the decompression speed though, Vandenne wrote."
If I understand this correctly, the point is to be compatible with zlib decompression. Obviously, you can bet much better compression with xz/lzma, for example, but that would be out of range for most browsers.
Escher was the first MC and Giger invented the HR department.
Actually, they state that the 3-8% better maximum compression than zlib is 2-3 orders of magnitude longer to compress.
I can't imagine what kind of content you're hosting that'd justify 3 orders of magnitude compression time to gain 3% compression.
Static content that only has to be compressed once, yet is downloaded hundreds of thousands or millions of times. 3-8% is a pretty significant savings in that case.
"None can love freedom heartily, but good men; the rest love not freedom, but license." --John Milton
Looking at the data presented in the pdf, it seems to me that gzip does a fantastic job for the amount of time it takes to do it.
Pfft. Another blatant corporate shill for gzip early in the Slashdot comments. You can't trust anybody on the internet these...
Oh, wait, the data actually does say that. Huh. That's... a really weird feeling, having someone on the internet legitimately say something's good and have data to back it up.
It improves over gzip by a mere 3% or so, but takes an order of magnitude longer to compress [...] it's practical merit is virtually nil.
Maybe it's useless to you as a developer(?), and to most people. However, you benefit from this kind of technology all the time. Compare this to video encoding, where powerful machines spend a heck of a lot of time and CPU power to gain extra 3%'s of compression to save bandwidth and give you a smooth viewing experience.
This tool could have many useful applications for any kind of static content that is frequently served, including web services, as well as embedded content in mobile games and other apps. Every little bit of space savings helps (as long as it isn't proportionally slower to expand, which the article says it stays comparable).