Google publishes JPEG encoder "Guetzli" open source

ByGreyloch

A Google-made JPEG encoder "Guetzli"Is published on GitHub. The generated JPEG file isLibjpegWhen comparing with the file size, file size will be reduced by 20 to 30% with comparable quality.

GitHub - google / guetzli
https://github.com/google/guetzli


In particular, it seems that news releases and the like have not been announced, but in October 2016 content posted by Jyrki Alakuijala in the forum Encode.ru (Google cash), Guetzli announced in 2013 as a new compression algorithm by GoogleZopfli"It is like a very slow JPEG encoder.

Regarding image quality and file size,ButteraugliWhen comparing the results with libjpeg using the same score (quality), it seems that the file size could be reduced by 35%. Incidentally,The Structural SIMilarity (SSIM)WhenPSNR-HVS-MThe score at 13% -14% has deteriorated. However, as far as the eye can see, "Block noise and others are decreasing and it is becoming beautiful."

Within the page of GitHub, the build method for POSIX (UNIX type OS such as Ubuntu and Arch Linux) and Windows,BazelThe build method using. Is introduced.

For Windows,Visual Studio 2015WhenVcpkgIs necessary. Since git.exe becomes necessary to use vcpkg,Git for WindowsIt is necessary to put in.

However,ReleaseSince the binary file is published on the page of ", there is also a way to use this. For Windows, download "guetzli_windows_x86.exe".


Since there is no GUI, it will be used from a command prompt like this. Since it is only an executable file, put it in an arbitrary folder and pass "input file name" and "output file name" and execute. The screen is a place where I converted "bees.png" which is distributed as sample.


As a result, the 174 KB PNG file shrinks to a 38 KB JPEG file. Inputable files are JPEG and PNG, and output is JPEG only.


This is the actual file you used. First of all, "bees.png" before conversion.


And this is "bees - v2.jpg" after conversion. The file size is 100 KB slightly shrunk, but the difference is almost unknown.


· 2017/03/17 9:50 Addendum
Google announced the release of the open source JPEG encoder Guetzli.

Research Blog: Announcing Guetzli: A New Open Source JPEG Encoder