UltraSvgz

This tool converts Scalable Vector Graphics (svgs) into the svgz format, a gzip compressed version thereof. The goal is that the tool first performs pre-processing stesp in the hope to reduce the size of the svg, which is basically an XML format, by removing useless spaces and hopefully eventually doing clever stuff to re-arrange and condense the contents in a lossless fashion. For this, we use a wide variety of tools, even including minimizing the file via free online services by uploading it and downloading the result (requires internet connection). Then, it takes the resulting data and pipes it through our UltraGzip tool to achieve a strong compression.

1. How to use UlrtraSvgz from the Command Line

Run java -jar ultraGzip-0.8.2-full.jar ARGUMENTS

The following arguments are supported:

• help print the help screen and all arguments
• svgIntensity=0...10 is the intensity of the svg processing. It ranges from 0 to 10, with 5 as default. UltraSvgz is a bit slow and uses many tools. 5 is a good default setting that will provide a very strong compression already. If you kick the setting up to 10, the tool will become slower.
• gzipIntensity=0...10 is the intensity used for the gzip compression. It ranges from 0 to 10, with 5 as default. UltraGzip is a bit slow and uses many tools. 5 is a good default setting that will provide a very strong compression already. If you kick the setting up to 10, the tool will become very slow, but maybe can squeeze out another 2 or 3 bytes.
• in=/path/to/file the path to the file with the source data to be compressed
• si compress contents written to stdin instead of a file. You must specify either in=... or the si option.
• out=/path/to/file the path to the file where the compressed data should be written to; if omitted and in is specified, an output file of the same name as the input will be generated in the input file's directory, but with an .svgz suffix.
• so write the compressed contents to stdout instead of a file. You must specify either out=... or the so option.
• dontCleanseWhiteSpace do not apply the internal routine for cleansing white space, because it might mess up double-spaces in text.
• help print the help screen

2. Requirements

If you are on Linux, the following utilities can improve the compression which can be achieved by installing the following additional programs:

• gzip (should already be installed)
• AdvanceCOMP (sudo apt-get install advancecomp)
• 7-zip (sudo apt-get install p7zip-full)
• zopfli (sudo apt-get install zopfli)
• pigz (sudo apt-get install pigz)
• Python 3's gzip library, which should normally be installed, too
• librsvg which can be installed via sudo apt-get install librsvg2-bin librsvg2-common.

An internet connection is needed to use the online minifiers (currently only https://www.svgminify.com)

3. Use as UltraSvgz in your Java Code

You can import the class UltraSvgz and then create a job which takes an array of byte as input data and returns an array of byte as compression result. The job implements Callable<byte[]>.

4. Licensing

This software uploads your SVG to https://www.svgminify.com, which is a free online svg minifying service provided Spikerog SAS, 15 Grand Rue, 11800 Laure Minervois, France. For this step, obviously the terms and conditions of this service and company hold.

This software directly uses scour as one of its internal components. Although our software here is GPL-3 licensed, scour is under the Apache License Version 2.0. The license of scour is contained in file LICENSE-scour.txt.

This software uses the linux binary version of svgcleaner as one of its internal components. Although our software here is GPL-3 licensed, svgcleaner is under the GPL-2. We obtained permission from Mr. Reizner via email to include his binaries this way. The license of svgcleaner is contained in file LICENSE-svgcleaner.txt.

This software indirectly uses JZlib as one of its internal gzip utilities. Although our software here is GPL licensed, JZlib is under a BSD-style license. The GPL licensing of our software therefore only applies to our own code, while the code of JZLib follows said BSD-style license, which is included in file LICENSE-JZlib.txt.

The binary distribution of our software may include binary versions of the above tools

5. Contact

If you have any questions or suggestions, please contact Prof. Dr. Thomas Weise of the Institute of Applied Optimization at Hefei University in Hefei, Anhui, China via email to tweise@hfuu.edu.cn with CC to tweise@ustc.edu.cn.