2 ms·

> JPEG is a standard; file size does not depend on what tool you use to create it. That’s simply not true. The specific choice of cosines can make a huge diffe

by donatj 8y ago

> JPEG is a standard; file size does not depend on what tool you use to create it. That’s simply not true. The specific choice of cosines can make a huge difference on compression while having nearly zero perceived visual difference. Most encoders however take a naive approach whereas something like Guetzli does an amazing job of compressing JPEGs way better than Photoshop ever could.

snowwrestler 8y ago
Guetzli is not appropriate as a general-purpose tool for optimizing website images. That's not really what it's designed for. I guess I should specify that I'm trying to give practical advice for people who think the linked blog post is instructive. For the vast majority of people, the simple act of thinking about, selecting, and testing the available settings in popular image optimization tools is going to have a far greater effect than the small optimizations (and sometimes big tradeoffs) that might come from cutting-edge stuff like Guetzli. The reward per effort of going from "not optimizing my images" to "purposefully optimizing my images using common tools" is typically much bigger than the step from the latter to "using the absolute best possible tool for each image."
- avhon1 8y ago
  > Guetzli is not appropriate as a general-purpose tool for optimizing website images. That's not really what it's designed for. What is it designed for? I downloaded and compiled it, and it seems to work quite well for the photographs on my website. The README says: > Guetzli is a JPEG encoder that aims for excellent compression density at high visual quality https://github.com/google/guetzli/ https://github.com/google/guetzli/
  - snowwrestler 8y ago
    Guetzli is for minimizing file size at the highest quality levels for JPEGs. Essentially, it's for nice looking photos. It only goes down to quality 84 and it takes a looonngg time to optimize. As a point of comparison, the author of the linked blog post dropped his JPEG quality to 70 and was happy with it. A JPEG at 70 (or lower), if you're happy with the look, has a good shot to be even smaller than the smallest Guetzli output. Generally speaking, the easiest gains in JPEG file size will probably come from just dropping the quality down and down in tests, and deciding what you can live with. But if you have to have the best quality, and have plenty of resources/time for encoding, then maybe Guetzli will be a good fit.
contravariant 8y ago
In that case you should probably still compress from an uncompressed original though.

by donatj 8y ago

snowwrestler 8y ago

Guetzli is not appropriate as a general-purpose tool for optimizing website images. That's not really what it's designed for. I guess I should specify that I'm trying to give practical advice for people who think the linked blog post is instructive. For the vast majority of people, the simple act of thinking about, selecting, and testing the available settings in popular image optimization tools is going to have a far greater effect than the small optimizations (and sometimes big tradeoffs) that might come from cutting-edge stuff like Guetzli. The reward per effort of going from "not optimizing my images" to "purposefully optimizing my images using common tools" is typically much bigger than the step from the latter to "using the absolute best possible tool for each image."

avhon1 8y ago
> Guetzli is not appropriate as a general-purpose tool for optimizing website images. That's not really what it's designed for. What is it designed for? I downloaded and compiled it, and it seems to work quite well for the photographs on my website. The README says: > Guetzli is a JPEG encoder that aims for excellent compression density at high visual quality https://github.com/google/guetzli/ https://github.com/google/guetzli/
- snowwrestler 8y ago
  Guetzli is for minimizing file size at the highest quality levels for JPEGs. Essentially, it's for nice looking photos. It only goes down to quality 84 and it takes a looonngg time to optimize. As a point of comparison, the author of the linked blog post dropped his JPEG quality to 70 and was happy with it. A JPEG at 70 (or lower), if you're happy with the look, has a good shot to be even smaller than the smallest Guetzli output. Generally speaking, the easiest gains in JPEG file size will probably come from just dropping the quality down and down in tests, and deciding what you can live with. But if you have to have the best quality, and have plenty of resources/time for encoding, then maybe Guetzli will be a good fit.

contravariant 8y ago

In that case you should probably still compress from an uncompressed original though.