[Coco] Re: File extensions

[John R. Hogerhuis]

On Thu, 2004-10-21 at 11:53, KnudsenMJ at aol.com wrote:

> How does PiNG (aka PNG) compare with JPEG?  ISTR trying it once or twice, but 
> wasn't impressed one way or the other.  I also STR that PNG is patent-free, 
> so Linux programs can use it -- which seems to be its main raison d'etre.  

PNG is lossless so it wouldn't be fair to compare its compression rates
to JPEG which is lossy. PNG is a replacement for GIF. GIF was an issue
for a while because of Unisys lossless compression patent encumberance.
I don't believe there are any significant issues with JPEG at the
moment.

Software freedom is an issue whenever you have a patent encumbered
protocol or format, and so it was unacceptable to the free world until
that patent expired. Software patents, unless an unrestricted license is
given, are incompatible with the GPL. The reason software patents are
incompatible is essentially because there is no way to charge the money
to pay patent tax to the patent holder, and still be able to
redistribute code freely.

I wouldn't say that patents are incompatible with Linux, though some are
practically incompatible with truly free variants of Linux like Debian
(no collection of tax for patent holder). Redhat, Novell, Mandrake et al
can bundle patent encumbered software in its supported (payware)
distributions, since the GPL does not prohibit or automatically require
redistributability of non-free software when it is merely aggregated
with free software. The vendor collects the tax and pays the patent
holder.

The same goes for sound file formats WMA and AAC. I won't use them and
feel no need to. MP3 is also encumbered, but free encoders and decoders
are widely disseminated and available. But I always rip to FLAC, and
encode via script to whatever my hardware requires, which is usually
high bit rate MP3.


How this all relates to goodness or badness of file extensions is beyond
me though... I think they are essentially orthogonal issues. A WMA
encoder or decoder is patent encumbered whether or not the files
produced by the encoder have a WMA extension.


-- John.