[News] Google's new algorithm shrinks JPEG files by 35 percent

[StyM]

https://www.engadget.com/2017/03/17/...by-35-percent/

For obvious reasons, Google has a vested interest in reducing the time it takes to load websites and services. One method is reducing the file size of images on the internet, which they previously pulled off with the WebP format back in 2014, which shrunk photos by 10 percent. Their latest development in this vein is Guetzli, an open-source algorithm that encodes JPEGs that are 35 percent smaller than currently-produced images.

As Google points out in its blog post, this reduction method is similar to their Zopfli algorithm that shrinks PNG and gzip files without needing to create a new format. RNN-based image compression like WebP, on the other hand, requires both client and ecosystem to change to see gains at internet scale.

If you want to get technical, Guetzli (Swiss German for "cookie") targets the quantization stage of image compression, wherein it trades visual quality for a smaller file size. Its particular psychovisual model (yes, that's a thing) "approximates color perception and visual masking in a more thorough and detailed way than what is achievable" in current methods. The only tradeoff: Guetzli takes a little longer to run than compression options like libjpeg. Despite the increased time, Google's post assures that human raters preferred the images churned out by Guetzli. Per the example below, the uncompressed image is on the left, libjpeg-shrunk in the center and Guetzli-treated on the right.

[BenchZowner]

More image quality decrease... no thank you!

[xlink]

More image quality decrease... no thank you!

Well it looks like the decrease is MOSTLY in the Hue and Saturation domains as opposed to the the vibrancy (which we're not as sensitive to).

Basically the data that gets distorted is the subset which humans are not as good at gauging and the data we're sensitive to is better preserved.

This is literally just using an optimization metric closer which better matches to our genetics.

Imagine better image quality at the same file size.

[AliG]

Shoutout to those who get it

[BenchZowner]

Well it looks like the decrease is MOSTLY in the Hue and Saturation domains as opposed to the the vibrancy (which we're not as sensitive to).

Basically the data that gets distorted is the subset which humans are not as good at gauging and the data we're sensitive to is better preserved.

This is literally just using an optimization metric closer which better matches to our genetics.

Imagine better image quality at the same file size.

I take such claims with a buttload of pinches of salt.
Google is "reinventing" the internet just when the average internet access speed globally is on the rise.
Most websites have image size limits already well under 500kb per image, and we are having something like 1MB/s average speed ( counting all the slow countries in the average, not excluding really slow ones ).
Facebook gives us terrible image quality and filesizes under 100kb per image in most cases... we don't need lower filesizes than that crap.
I highly doubt that at the same size Google's algorithm does something useful ( for example avoid creating compression halos ).

[xlink]

I take such claims with a buttload of pinches of salt.
Google is "reinventing" the internet just when the average internet access speed globally is on the rise.
Most websites have image size limits already well under 500kb per image, and we are having something like 1MB/s average speed ( counting all the slow countries in the average, not excluding really slow ones ).
Facebook gives us terrible image quality and filesizes under 100kb per image in most cases... we don't need lower filesizes than that crap.
I highly doubt that at the same size Google's algorithm does something useful ( for example avoid creating compression halos ).

I'm just imagining facebook with non- quality.

[alpha0ne]

I can just see all the photo sites adopt this reduction in size @ the cost of quality and clarity................................NOT

[MirageSys]

Looks apparent. You can see the green getting markedly de-saturated.

[NEOAethyr]

Seems ok to me, better then std lib-jpeg it seems.
This should bring higher quality jpegs on the net, as long as they are kept the same size as previous stuff.

So I'm all for this .