GIMP plugin to enable exporting via Google's Perceptual JPEG encoder.

Taken from the Googe Guetzli GitHub Page:

Guetzli is a JPEG encoder that aims for excellent compression density at high visual quality. Guetzli-generated images are typically 20-30% smaller than images of equivalent quality generated by libjpeg. Guetzli generates only sequential (nonprogressive) JPEGs due to faster decompression speeds they offer.

Uncompressed 137.3kB:

Compressed 19.4kB:

First of all, install gimp-python and libpng using the following command:

sudo dnf/apt install libpng-devel gimp-python

This plugin requires that you set up Guetzli. The easiest way to do this is to download the newest release from the following page and unzip the binary to your preferred path.

Once you have done that, ensure that the binary is executable by running the following in your terminal:

chmod +x /path/to/binary/guetzli

Now append the path to the Guetzli binary to ~/.profile.

export GUETZLI="/path/to/binary/guetzli"

Once complete, clone this project and copy over the plugin to the default local plugins directory and make it executable.

git clone https://github.com/KeironO/gimp-guetzli/
cp gimp-guetzli/src/guetzli-export.py ~/.config/GIMP/2.10/plug-ins
chmod +x ~/.config/GIMP/2.10/plug-ins/guetzli-export.py

0. Open the image you want to export in GIMP.
1. File > Export As
2. Select File Type (By Extension) > Google Guetzli (JPEG)
3. Change the filename to whatever you want.
4. Export
5. Drag the slider to whatever compression quality you want and click export.
6. ???
7. PROFIT

Note: Guetzli uses a large amount of memory. You should provide 300MB of memory per 1MPix of the input image.

And also:

Note: Guetzli uses a significant amount of CPU time. You should count on using about 1 minute of CPU per 1 MPix of input image.

Oh, and another thing:

Note: Guetzli assumes that input is in sRGB profile with a gamma of 2.2. Guetzli will ignore any color-profile metadata in the image.

Code released under the MIT license.