Documenting the GIMP's file format resolves technical and political issues (NewsForge) [LWN.net]

NewsForge looks at the GIMP's file format. "The GIMP finally has a documented file specification. The free image editor has long been criticized over the fact that its native image format XCF was not publicly documented. Recently the issue came to a head, sparked unintentionally by discussions over the proposed OpenRaster graphics interchange format. Once the argument cooled off, however, an independent developer decided to tackle the problem head on -- to the benefit of all."

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Documenting the GIMP's file format resolves technical and political issues (NewsForge)

Posted Aug 8, 2006 6:34 UTC (Tue) by lacostej (guest, #2760) [Link] (6 responses)

Once again the benefits of Open Source show. It only took one developper, not even a Gimp one, to write the initial specs.

Benefits of Open Source

Posted Aug 8, 2006 7:29 UTC (Tue) by Felix.Braun (guest, #3032) [Link] (5 responses)

The documentation of the file format was always available, in source code. After all the source code of the parser is the most detailed specification of a file format. All it took was one developer to rephrase that specification into proper english. IMHO that is the real beauty of Open Source.

Benefits of Open Source

Posted Aug 8, 2006 13:18 UTC (Tue) by ordonnateur (guest, #6652) [Link] (3 responses)

Not quite. The source code does define how a file is created and subsequently read, but subtle differences in compiler implementation or hardware could mean differences in the format of the file itself. Documentation of a file format defines the file itself, not the process by which a file is created nor what an application might do with it.

Benefits of Open Source

Posted Aug 9, 2006 7:17 UTC (Wed) by Wol (subscriber, #4433) [Link] (2 responses)

Definition of the file format also constrains new features.

With regard to the OP's point, I explicitly defined a file format in my project because I wanted it to be cross-platform. It's all very well saying "this is an integer", but 2 bytes or 4? Big endian or little? etc etc.

And with regard to my point, one only has to look at the WordPerfect specification (and compare it to Word!!!). The WP spec defines text and control sequences. And it also defines the form of a control sequence. That's why WP6 can happily read a WP13 document - if it hits an unrecognised control sequence, (a) it can recognise it as such, and (b) it knows enough to pick out the start and end, and flag it in the editing screen as "unknown". If the user leaves it alone, WP does likewise, and when it saves it, it saves it intact for the next time the user uses WP13, at which point the sequence will be recognised and acted upon.

Clearly defined file formats can give you *forwards* compatibility!

Cheers,
Wol

Benefits of Open Source

Posted Aug 9, 2006 16:16 UTC (Wed) by dberkholz (guest, #23346) [Link] (1 responses)

> Definition of the file format also constrains new features.

That's why the format should include a version number.

Benefits of Good Definitions

Posted Aug 15, 2006 2:23 UTC (Tue) by xoddam (subscriber, #2322) [Link]

> That's why the format should include a version number.

Versioning lets you explicitly obsolete old software, such that the old
software knows it's trying to read a future file format and can fail
gracefully. But defining the syntax of the file in an extensible way as
described above is a much more powerful facility -- reading and writing
future formats and features is actually *supported*.

This has nothing to do with open source btw, and everything to do with
good engineering and forward planning, in the best sense not the sense of
'planned obsolescence'.

Benefits of Open Source

Posted Aug 9, 2006 16:09 UTC (Wed) by Zenith (guest, #24899) [Link]

This line of arguing merely complements what Microsoft was arguing in its case against the European Commision, and as the EC stated, it is not true, for reasons that the other posters have nicely outlined.