RE: SVGZ support - why isn't there any?

Funnily enough, it’s the use case you hinted at.

We use SVGs for the electronic maintenance manuals for aircrafts, from 737, to 787, from B52 to VC25 and V22.
And those manuals will have thousands to tens of thousands of very complex graphics that come out of engineering publishing systems.
These electronic maintenance manuals need the ability to be stand alone, and take up less space, for example, for the 737 there is a separate manual possibly per airline, or for the F15 per tail number, due to the many variants.  And all that data needs to be backed up in the technical publications system organization, as well as managed.  When the SVG version is an order of magnitude larger than the CGM it is based upon, as an example a CGM of 23KB produces an SVG of 212KB, and you multiply that up by the number of graphics per aircraft, by the variants, it ends up being a lot of data.

Addressing some of that issue was one of the motivations behind creating the SVGZ specification I would have thought.
For a while it seemed like the issue was Firefox was just behind in implementing, but then the chromium folks thought, well if everyone else is jumping off the bridge, so should we.

There is a huge volume of graphics data in use, that is technical vector based, that benefits from SVG as the products can easily be ported from desktop and laptops to mobile devices without network access, and most of it sits behind corporate firewalls and isn’t visible to web statistics collecting engines.

Thomas Smailus, Ph.D.,  P.E., F.NSPE
Boeing Information Technology
Mobile: 425/553-8342

From: Jacopille, David <>
Sent: Friday, October 20, 2023 8:04
To: Smailus (US), Thomas O <>;
Subject: [EXTERNAL] Re: SVGZ support - why isn't there any?

EXT email: be mindful of links/attachments.


There are a lot of options out of Illustrator to save pretty compact SVG files without compression… removing Illustrator file data, reducing precision, using Illustrator (or the better Astute Graphics plugin) to non-destructively simplify paths, save as tiny SVG, etc..  Using these techniques you can often get images, like a chart, to be smaller in SVG than in pixels.  This can produce very small SVG files that have such density of data that further compression might not be as effective as on a ‘fatter’ SVG file.

I’m not sure what the use case would be for non-web, file based access to SVG files other than opening them up in an editor.  Compression is not likely to be needed for this.

If you had an extremely complex diagram or set of diagrams that you wanted to host via web page, such as the entire maintenance manual for a Boeing 747-8, and you wanted the images to be in SVG format… then you might be wondering about compression.  I recall from A&P school the 747 maintenance manual in printed form was about 20 feet thick and probably had > 10K diagrams.  But even in this use case I would think that the use case for SVGZ would be limited.  You could load 100,000 1MB SVG images into RAM on web server startup.   We routinely deliver 25MB data files from memory via web sockets to web clients in < 2 seconds.  In other words, other architectural solutions might compensate for lack of SVGZ support.

So, yes, SVGZ support would be nice, but I’m struggling to think of an essential use case.  I’d love to hear one though.

David Jacopille
MFS Investment Management
Boston, MA

From: "Smailus (US), Thomas O" <<>>
Date: Thursday, October 19, 2023 at 7:21 PM
To: "<>" <<>>
Subject: SVGZ support - why isn't there any?
Resent-From: <<>>
Resent-Date: Thursday, October 19, 2023 at 7:20 PM

External email. Please do not click on links or attachments unless you recognize the sender.

In a case of, why way does this now not work?  I’m wondering why now (for some years) none of the main web browser engines (which are the defacto SVG display engines) do not support SVGZ, the compressed SVG format?

Is this a case of not seeing there are indeed use cases they are ignoring, or a case of the developers not being cognizant of the state of SVG usage outside of web server delivered content?

There is a real need for supporting SVGZ from FILE: protocol, as a lot of SVG graphics are stored on file systems and accessed locally without any service or web server involvement.

Thomas Smailus, Ph.D., P.E., F.NSPE
Senior Advanced Information Technologist
Boeing Information Technology
SVG Forum CoP Lead | Intelligent Graphics SVG Lead
EO&T LEAP - 2011 / BR&T HIPO - Cadre 1
The Boeing Company; P.O. Box 3707 MC 2H-52; Seattle, WA 98124-2207
Email:<>       Tel: 425/373-2850        Fax: 425/865-5791

MFS Email system made the following annotation
This email communication and any attachments may contain proprietary, confidential, or privileged information. If you are not the intended recipient, you are hereby notified that you have received this email in error and that any review, disclosure, dissemination, distribution or copying of it or its contents is prohibited. The sender does not waive confidentiality or any privilege by mistransmission. If you have received this email in error, please notify the sender immediately, delete this email, and destroy all copies and any attachments.

Received on Friday, 20 October 2023 15:56:42 UTC