'Re: Vector format/metafile for KOffice (Re: [Karbon14] misc)'

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List:       koffice-devel
Subject:    Re: Vector format/metafile for KOffice (Re: [Karbon14] misc)
From:       Vadim Plessky <lucy-ples () mtu-net ! ru>
Date:       2002-10-31 10:00:04
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On Thursday 31 October 2002 12:00 pm, Dirk Schönberger wrote:
[...]
|
|  > It the only system/library which support 16-bit per pixel component, and
|  even
|  > 32-bit per pixel component (since Aud.2002) quantum depth.
|  > So, you can convert/transform 48-bit RGB (64-bit RGBA) images with help
|  > of ImageMagick.
|  > And AA-renderer inside IM would produce 48-bit RGB images, too (out of
|  WMFor > SVG files)
|  > GS, GNOME2/GTK2, Qt3/KDE3 are limited to 8-bit per pixel (32-bit RGBA),
|  > AFAIK.
|
|  I am not convinced that I really need more than 8bit colour components.
| The main reasons for its useage reolved around lossless useage of images
| gathered from digital cameras, and I don't have such a thing, yet.
|

Not only cameras, but also scanners.
You can expect somethingloke 12-bit per componnet output from professional
digital camera (my father uses such camera, output image is 17MB
uncompressed/raw format)

If you take Sinar camera - it can prodcue 14-bit per pixel component output.
Plus move matrix/exposition in sub-pixel steps, allowing to take 16
expositions from one object, and later calculate final image as composition
of thos 16.
I need to say here thatSinar camera are really *expensive*.
But you will get output file up to 1GB (per one object/shoot), something to
play with :-)

And real benefit of 16-bit processing is not "lossless images" (you will miss
some details anyway), but "lossless processing".
You process image in 16-bit, than convert to 8-bit when everything is done.

Below is a list of interesting link/extracts related to 16-bit image
processing (and "4096 shades of gray").
Hope you wil find this info useful.

----------------------------------------------------------------------
http://www.johnpaulcaponigro.com/faqs/editing.html
Why edit in 16-bit ?
 Editing in 16-bit is nondestructive, that is it won't cause combing in your
histogram, or posterization. Why? In a few words, because it contains more
shades of gray or steps between tones/colors.

An RGB file is composed of three channels: red, green, and blue. Each of these
channels are grayscale images that describe how much of each corresponding
color is in the RGB file. For instance, where the red channel is black, the
file contains no red; conversely, where the red channel is white, the file
contains the maximum amount of red. When the three channels are combined, a
full color image is produced. The highter the bit depth the more grays in
each channel. With more grays in each channel there are more points to snap
to when editing, reducing posterization and creating smoother gradations.

- - - - - - - - - - - - - - - -
http://www.sinarbron.com/bitdepth.htm
While Sinar digital backs capture a full 42 bits of data, todays electronic
publishing systems are designed to handle only 24 bits. Despite this
limitation, virtually all digital cameras and scanners capture more than 24
bits. Capturing more data and then reducing it down to 24 bit gives much
better tonality than just capturing 24 bits to begin with. The Sinar
CaptureShop capture software gives you total control over how your 42 bits of
capture data is exported down to 24 bits of usable data. This ensures that
you have the detail and tonal range you need in your highlights, midtones and
shadows.

- - - - - - - - - - - - - - - -
http://www.photofocus.com/zine5/zine3.htm
Scanning in 16-Bit mode.  The right way to do things
By Scott Bourne

- - - - - - - - - - - - - - - -
http://www.phototechmag.com/previous-articles/mar-bond99.htm
Ron Harris. A DIGITAL APPROACH TO BLACK AND WHITE
March/April 1999
My approach has been to use a Hasselblad 2 1/4 camera with either Kodak T-max
100 or Kodak Technical Pan films, and then scan the negatives into Photoshop.
After working with the image in Photoshop to get the desired tones and
sharpness, I print the image on an inkjet printer. My digital darkroom
adjustments have been primarily limited to whatever is possible in the
darkroom, such as unsharp masking, bleaching, dodging, burning, contrast and
brightness adjustments; however, the methods and the tools used are
necessarily different.
- - - - - - - - - - - - - - - -

http://www.kodak.com/global/en/service/faqs/faq4502.shtml
Frequently Asked Questions. Teleradiology
Updated 19 January 1999.

6. What is meant by image-bit size?
Digital images, whether viewed on a computer monitor, transmitted over a phone
line, or stored on a hard disk or archival medium, are pictures that have a
certain spatial resolution.

The spatial resolution, or size, of a digital image is defined as a matrix
with a certain number of pixels (information dots) across the width of the
image and down the length of the image. The more pixels, the better the
resolution. This matrix also has depth. This depth is usually measured in
bits and is commonly known as shades of gray: a 6-bit image contains 64
shades of gray; 7-bit, 128 shades; 8-bit, 256 shades; and 12-bit, 4096
shades.
- - - - - - - - - - - - - - - -
http://www.fotocare.com/html/product.asp?gId &mid'4
What is bit depth?
...
But even these 256 levels aren't enough to properly represent the full tonal
range of an image. Many digital camera manufacturers use a depth of 12 bits
per pixel, which gives them 4096 shades to work with. But as the illustration
shows, even this many shades might not be adequate, especially in the
shadows.
The Leaf DCB was designed with a thermo-electrically cooled CCD. During normal
operation, the chip is cooled to about 33°F. At lower temperatures, the
electronic noise in the shadows is reduced, allowing the camera to read data
farther down the scale.

When there's more good information available, you can achieve a greater bit
depth. This is what allows a Leaf back to capture 14 bits of data. 14 might
not sound like much more than 12, but don't forget that bits work
exponentially. While 12 bits give you 4096 levels, 14 bits give you 16,384
levels - 4 times the tonal information of a 12 bit capture.
...
While the Leaf DCB captures a full 42 bits of data, today's electronic
publishing systems are designed to handle only 24 bits. Despite this
limitation, virtually all digital cameras and scanners capture more than 24
bits.

Capturing more data and then reducing it down to 24 bit gives much better
tonality than just capturing 24 bits to begin with. The Leaf capture software
gives you total control over how your 42 bits of captured data is exported
down to 24 bits of usable data. This ensures that you have the detail and
tonal range you need in your highlights, midtones and shadows.
- - - - - - - - - - - - - - - -
http://www.hardware-corner.net/reviews/microtekc6.php

Sample Depth
Color Mode:
* 12 bit input / output per RGB color channel; 68.7 billions of colors;
Grayscale mode:
* 12 bit input / output, 4096 shades of gray;
Black and White mode:
* 1-bit, 64 shades of gray simulated

Optical Resolution: 600 x 1200 dpi
Interpolated resolution: 9600 x 9600 dpi
Maximum scan size: 8.5" x 11.7"

- - - - - - - - - - - - - - - -
http://www.libpng.org/pub/png/pngintro.html

For image editing, either professional or otherwise, PNG provides a useful
format for the storage of intermediate stages of editing. Since PNG's
compression is fully lossless--and since it supports up to 48-bit truecolor
or 16-bit grayscale--saving, restoring and re-saving an image will not
degrade its quality, unlike standard JPEG (even at its highest quality
settings). And unlike TIFF, the PNG specification leaves no room for
implementors to pick and choose what features they'll support; the result is
that a PNG image saved in one app is readable in any other PNG-supporting
application.
- - - - - - - - - - - - - - - -
http://swehsc.pharmacy.arizona.edu/exppath/micro/digimageintro.html
Digital Imaging
(Experimental Pathology Core : Microscopy & Imaging Resources)
This page: Pixels, Resolution, Bit-depth, Color, File formats, Human Vision

- - - - - - - - - - - - - - - -
http://www.matrox.com/mga/media_center/press_rel/2002/fose_mediaad.cfm
FOSE 2002
Matrox Graphics Inc. will demonstrate specialized graphics solutions for
government integrators and OEMs, including its powerful new Matrox MED2mp
graphics card targeted toward precision grayscale markets such as military
applications and medical imaging,
...
Bringing excellence to the precision grayscale market, the recently announced
Matrox MED2mp graphics card is the ultimate solution for specialized military
applications requiring high-precision grayscale imaging such as the viewing
of satellite and medical imagery. Displayed on two Siemens Display
Technologies grayscale monitors, attendees will be able to experience
first-hand the superb image quality of the Matrox MED2mp card. Incorporating
support for 10-bit per channel grayscale accuracy from an 8-bit input, this
imaging card can output images in 10-bit grayscale on two or four analog
displays. The Matrox MED2mp is a PCI graphics card equipped with 8MB of SGRAM
and a 250 MHz RAMDAC per chip, yielding crystal-clear images at resolutions
of up to 1600 x 1200 on each display in landscape mode, and 1280 x 1600 on
each display in portrait mode.
- - - - - - - - - - - - - - - -

--

Vadim Plessky
http://kde2.newmail.ru  (English)
33 Window Decorations and 6 Widget Styles for KDE
http://kde2.newmail.ru/kde_themes.html
KDE mini-Themes
http://kde2.newmail.ru/themes/

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