Dave stumbled on a neat little photo editor while tricking out his
old Vaio (P3/650 MHz, 192M RAM) and looking for lightweight apps.
It's called Fotoxx and it's quite impressive: easy to use and packed
with useful features.
So I wrote about it in this week's Linux Planet article:
Fotoxx,
the Greatest Little Linux Photo Editor You've Never Heard Of.
At first, I was most impressed by the Warp tool -- much easier to
use than GIMP's IWarp, though it's rather slow and not quite as
flexible as IWarp. But once I got to writing the article, I was
blown away by two additional features: it has an automatic panorama
stitcher and an HDR tool. GIMP doesn't have either of these
features, at all.
Now, panorama stitching used to be a big deal, but it isn't so much
any more now that Hugin has gotten much easier to use. (My article
in two weeks will be about Hugin.) Fotoxx isn't quite that flexible:
it can only stitch two images at a time, and can't handle images
with a lot of overlap. (But Hugin has some limitations too.)
But HDR -- wow! I've been meaning to learn more about making HDR
images in GIMP -- although it has no HDR tool, there are plug-ins to
make it a bit easier to assemble one, just like my Pandora plug-in
makes it a little easier to assemble panoramas. But now I don't need
to -- fotoxx handles it automatically.
I won't be switching from GIMP any time soon for regular photo
editing, of course -- GIMP is still much more flexible. But fotoxx
is definitely worth a look, and I'll be keeping it installed to make
HDR images, if nothing else.
Tags: writing, linux, graphics, panorama, HDR
[
14:44 Aug 12, 2010
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Dave and I recently acquired a lovely trinket from a Mac-using friend:
an old 20-inch Apple Cinema Display.
I know what you're thinking (if you're not a Mac user): surely
Akkana's not lustful of Apple's vastly overpriced monitors when
brand-new monitors that size are selling for under $200!
Indeed, I thought that until fairly recently. But there actually
is a reason the Apple Cinema displays cost so much more than seemingly
equivalent monitors -- and it's not the color and shape of the bezel.
The difference is that Apple cinema displays are a technology called
S-IPS, while normal consumer LCD monitors -- those ones you
see at Fry's going for around $200 for a 22-inch 1680x1050 -- are
a technology called TN. (There's a third technology in between the
two called S-PVA, but it's rare.)
The main differences are color range and viewing angle.
The TN monitors can't display full color: they're only
6 bits per channel. They simulate colors outside that range
by cycling very rapidly between two similar colors
(this is called "dithering" but it's not the usual use of the term).
Modern TN monitors are
astoundingly fast, so they can do this dithering faster than
the eye can follow, but many people say they can still see the
color difference. S-IPS monitors show a true 8 bits per color channel.
The viewing angle difference is much easier to see. The published
numbers are similar, something like 160 degrees for TN monitors versus
180 degrees for S-IPS, but that doesn't begin to tell the story.
Align yourself in front of a TN monitor, so the colors look right.
Now stand up, if you're sitting down, or squat down if you're
standing. See how the image suddenly goes all inverse-video,
like a photographic negative only worse? Try that with an S-IPS monitor,
and no matter where you stand, all that happens is that the image
gets a little less bright.
(For those wanting more background, read
TN Film, MVA,
PVA and IPS – Which one's for you?, the articles on
TFT Central,
and the wikipedia
article on LCD technology.)
Now, the comparison isn't entirely one-sided. TN monitors have their
advantages too. They're outrageously inexpensive. They're blindingly
fast -- gamers like them because they don't leave "ghosts" behind
fast-moving images. And they're very power efficient (S-IPS monitors,
are only a little better than a CRT). But clearly, if you spend a lot
of time editing photos and an S-IPS monitor falls into your
possession, it's worth at least trying out.
But how? The old Apple Cinema display has a nonstandard connector,
called ADC, which provides video, power and USB1 all at once.
It turns out the only adaptor from a PC video card with DVI output
(forget about using an older card that supports only VGA) to an ADC
monitor is the $99 adaptor from the Apple store. It comes with a power
brick and USB plug.
Okay, that's a lot for an adaptor, but it's the only game in town,
so off I went to the Apple store, and a very short time later I had
the monitor plugged in to my machine and showing an image. (On Ubuntu
Hardy, simply removing xorg.conf was all I needed, and X automatically
detected the correct resolution. But eventually I put back one section
from my old xorg.conf, the keyboard section that specifies
"XkbOptions" to be "ctrl:nocaps".)
And oh, the image was beautiful. So sharp, clear, bright and colorful.
And I got it working so easily!
Of course, things weren't as good as they seemed (they never are, with
computers, are they?) Over the next few days I collected a list of
things that weren't working quite right:
- The Apple display had no brightness/contrast controls; I got
a pretty bad headache the first day sitting in front of that
full-brightness screen.
- Suspend didn't work. And here when I'd made so much progress
getting suspend to work on my desktop machine!
- While X worked great, the text console didn't.
The brightness problem was the easiest. A little web searching led me
to acdcontrol, a
commandline program to control brightness on Apple monitors.
It turns out that it works via the USB plug of the ADC connector,
which I initially hadn't connected (having not much use for another
USB 1.1 hub). Naturally, Ubuntu's udev/hal setup created the device
in a nonstandard place and with permissions that only worked for root,
so I had to figure out that I needed to edit
/etc/udev/rules.d/20-names.rules and change the hiddev line to read:
KERNEL=="hiddev[0-9]*", NAME="usb/%k", GROUP="video", MODE="0660"
That did the trick, and after that acdcontrol worked beautifully.
On the second problem, I never did figure out why suspending with
the Apple monitor always locked up the machine, either during suspend
or resume. I guess I could live without suspend on a desktop, though I
sure like having it.
The third problem was the killer. Big deal, who needs text consoles,
right? Well, I use them for debugging, but what was more important,
also broken were the grub screen (I could no longer choose
kernels or boot options) and the BIOS screen (not something
I need very often, but when you need it you really need it).
In fact, the text console itself wasn't a problem. It turns out the
problem is that the Apple display won't take a 640x480 signal.
I tried building a kernel with framebuffer enabled, and indeed,
that gave me back my boot messages and text consoles (at 1280x1024),
but still no grub or BIOS screens. It might be possible to hack a grub
that could display at 1280x1024. But never being able to change BIOS
parameters would be a drag.
The problems were mounting up. Some had solutions; some required
further hacking; some didn't have solutions at all. Was this monitor
worth the hassle? But the display was so beautiful ...
That was when Dave discovered TFT
Central's search page -- and we learned that the Dell 2005FPW
uses the exact same Philips tube as the
Apple, and there are lots of them for sale used,.
That sealed it -- Dave took the Apple monitor (he has a Mac, though
he'll need a solution for his Linux box too) and I bought a Dell.
Its image is just as beautiful as the Apple (and the bezel is nicer)
and it works with DVI or VGA, works at resolutions down to 640x480
and even has a powered speaker bar attached.
Maybe it's possible to make an old Apple Cinema display work on a Mac.
But it's way too much work. On a PC, the Dell is a much better bet.
Tags: linux, tech, photo, graphics, monitor, S-IPS, TN, ADC, DVI
[
20:57 Nov 15, 2008
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]
![[Hugin panorama]](http://www.linuxplanet.com/graphics/screenshots/Fig2-fastpreview_1.jpg)
A couple of weeks ago in my
Fotoxx
article I discussed using Fotoxx to create panoramas.
![[feed]](http://shallowsky.com/images/logos/feed-icon-14x14.png){kind=icon}