Printing - fun
Good 'ol Slashdot has an article
today on
printing. One of the comments links my last diary here,
spinning it as a "negative review of Argyll." Sigh.
Actually, my latest results with Argyll are very
encouraging. I've made a number of profiles since the last
post, and each is quite a bit better than the previous
version. I now feel I have a good understanding of why
my amateurish attempts had the quality problems they did.
I really like doing this kind of work. Learning and doing is
the true spirit of free software - learning without doing
gets you academic sterility, and doing without learning is
all too often the way things are done in proprietary
software.
Color science is continuing to evolve quickly. I think
people got seduced by the fact that you can measure color
rigorously and precisely, and characterize the color
transformations done by actual devices such as monitors and
printers. Color management, then, should be a snap - just
make the colors on the printer match the colors on the
screen, and you're done.
In fact, the way colors are perceived on the screen and on
paper are quite different. Even worse, not all printers (or
papers) are created equal. A ratty old inkjet on plain paper
can't produce anywhere nearly the same range of
colors as an Epson 870 on photo glossy. You have to do
something with the colors outside the printer's
capabilities. This process is called "gamut mapping", and
the scientific understanding of how to best accomplish has
only recently started to come into focus. Two important
works from the last five years include Jan Morovic's thesis,
and Fairchild's
paper on hue linearization.
The goal of all this, I think, is to package up "best
practices" in color management so that mere mortals can make
and use color profiles with good results, without having to
understand all the details of color science or our
particular implementation. It still won't be for everybody -
spectrophotometers still run around $1500, but I'd like for
there to be a good solution for people serious about graphic
arts.
Printing - not fun
I don't like standards committees, and I get the distinct
impression that they don't like me. Thus, I think that one
of the keys to happiness for me is to never get involved
with a standards committee again.
I've been working on a protocol for hooking in printer
drivers, called IJS (it's based on HP's hpijs, but
driver-independent). I think it's going pretty well - HP's
latest driver uses the IJS protocol, I've drafted a halfway
decent spec,
and I expect versions of Ghostscript to ship with IJS built
by default pretty soon.
But life can't be so simple. As it turns out, the Free Standards
Group has a Printing
Working Group (not to be confused with the
Printer Working Group, which is responsible for IPP)
that is working on a standard to do pretty much the same
thing as IJS. Well, I guess what they say is true: the great
thing about standards is that there are so many to choose
from.
I sent a rather passionately worded mail to their mailing
list, requesting that they adopt wire protocol compatibility
with IJS, but I'm really unsure how best to proceed. If I
was a masochist with lots of extra time on my hands, I'd
take active part in the PWG<2> and try to bully them
into making a good standard, but it's just not how I
want to spend my time.
I guess I'll be updating here as this thing plays out.
OpenSourceJapsEye
Awww, how cute. Our first determined troll.
These posts don't personally bother me that much, but I can
imagine others not liking them. I think there's a good
chance that our troller will get bored and go away, but of
course I might be wrong. Obviously, there are other
community sites where trolling is a deeply integrated part
of the culture.
Amusingly, the concept of the trust metric seems to be
working - OSJE is not certified. The problem is that one of
the most popular parts of this site (the recent diary
summary) doesn't use the trust metric at all. The simple
thing to do would be to tighten up the recent diary list to
only include cert'ed members. In the past, uncert'ed diary
posts have been a good thing, largely because people can
talk about the free software work they've done and thus
elicit certifications. But at this point, it might be worth
sacrificing, and I would ask that people use other channels
of communication than Advogato diaries to get initial certs.
After all, the site is pretty well established now. It
should be reasonably easy for any serious free software
developer to find somebody with an account here who they
know well enough to ask for a cert.
I'm disheartened to hear reports that Advogato's S/N ratio
is declining. It may well be true. If so, I'm not sure why.
I fear that one reason may be that there's simply not as
much interesting stuff happening in the free software world
these days. It's hard for me to evaluate.
In any case, I think Advogato's S/N is pretty good. It's not
fabulous, though. I'd like it to be better, and am
definitely interested in tweaking the site to make it so. Of
course, this work has to compete for time with the other
stuff I'm doing (like actually doing free software,
not to mention finishing my thesis), and it's especially
hard to find motivation when I'm so unsure what would
actually be effective. But I'm sure I'll find some more time
to play with this site over the next few months.
As always, constructive suggestions are welcome.
Family
My mom is coming tomorrow (Christmas Eve). We'll all pile in
the car
and pick her up from the airport. It ought to be fun.
Max is at such a beautful age right now. Watching him begin
to master
language is such a joy. My favorite word of today was
"chicken soup",
which suggests that he's just about to break through the
2-syllable
barrier. He asked for "Goodnight Moon" tonight, and I read
it to him,
twice. So sweet.
He's also into physical and spatial stuff. Alan and I were
playing Hoppers
this afternoon, and Max of course wanted to play too. He
didn't seem
to grasp the rules of the game at all (not surprising), but
he did
very much enjoy putting the little frogs on their pegs, and
the
patterns that resulted.
Alan is having a bit more of a difficult time right now. He
spends a
fair amount of time these days in a bad mood, easily getting
frustrated, and obnoxious to boot. Heather and I have noted
that it
seems to be linked to time spent playing video games,
particularly
shooters like Nanosaur
(which ordinarily we wouldn't let him play, but gave in
because he
likes dinosaurs so much). So we're going to cut down on the
amount
of time for video games and see if that helps.
His new passion continues to be stories. I'm reading him
"Jurassic
Park" now, and he's for the most part enjoying it, although
it's a
little too talky for his taste. It's amazing to me that he
understands
the story, not just what's going on, but the structure and
texture of
it as well. Early on in the book, he foresaw that Tina would
get
attacked by a dinosaur before any such thing was mentioned.
Pretty
basic for any fan of sci-fi thrillers, but impressive to me
from a
five year old.