At 11:14 AM 6/13/2004 -0700, Bryce Harrington wrote:

On Sun, 13 Jun 2004, Glenn Randers-Pehrson wrote:

...

At 10:04 PM 6/12/2004 -0700, Bryce Harrington wrote:

...

I've completed writing some code for processing collections of SVG files to validate their metadata (title, author, license). The code is packaged and released to CPAN:

http://search.cpan.org/~bryce/SVG-Metadata-0.01/

It includes the following:

SVG::Metadata - A module for parsing and accessing an SVG's metadata, including title, author, license, and keywords.

svg_validate - A script for scanning through a collection of SVG files and extracting ones with valid metadata. It also automatically generates png's for each (using inkscape) and metadata text files.

For the past few weeks I have been attempting to get a "License" keyword approved by the PNG group, so far without success. The group seems to feel that licensing info should go in a textual chunk with the "Copyright" keyword, even if there is no copyright. I'll know more on June 23 when the group finishes voting.

We could follow that recommendation, or we could of course use an un-registered "License" keyword or even "OCAP License" keyword. It would be good to use the same keywords in PNG and SVG metadata.

Agreed. But if they end up using the Copyright keyword, that's probably not an issue.

Do you know of tools for editing the metadata in a PNG file? I could modify the script to include a metadata insertion into the generated PNG files as part of the process.

pngcrush will do it. I wanted to resolve issues with the PNG group before writing it up.

For example,

pngcrush -text b "Copyright" \ "copyright 2000 svg-scribblers, Inc. Placed in Public Domain June 2004" \ -text b "Author" "J. F. Scribbler, www.svg-scribblers.com" \ in.png out.png

The "b" means place the resulting tEXt chunk before the IDAT chunks. Otherwise use "a" to put it after the IDAT.

Glenn