From: seah@ee.rochester.edu (David Seah)
Newsgroups: alt.cyberpunk.tech
Subject: Re: Resolution Vs Colors
Date: 15 Dec 92 13:58:58 GMT
Organization: Univ of Rochester, College of Engineering and Applied Science

Hmmm...the Resolution Vs Colors argument!  

In article <PHUTTER.57.724270899@cardinal.sc107.wesleyan.edu> PHUTTER@cardinal.sc107.wesleyan.edu (Macbeth) writes:
>In article <12DEC199200340539@sigma.tamu.edu> tww2568@sigma.tamu.edu (WEEKS, THOMAS WILLIAM) writes:
>>Yes... the new higher resolutions are nice, but all in all, only DTP and other
>>such resultion greedy applications need the such.. for the human eye, dealing w
>>with lower contrast 256+ color pallets, you'll find MORE COLORS is better
>>than higher res....

A distinction you have to make is what your application is.  High _spacial_
resolution provides more quantitative information, while high _color_
resolution provides more of a qualitative one.  What does that mean?
With high rez screens, you can show more characters of a more legible
font and stuff more little symbols in the same amount of screen real estate.
That's quantitative.  With lots of colors, you can make things look nice
with subtle shading and snappy highlighting.  You can use color to do stuff
like weather maps, which show the amount of precipitation or cloud cover
through the use of different shades of color.  That's qualitative.  You
can't extract hard data from this kind of display unless you severely
limit the number and kinds of color.

There is a limit to the number of distinguishable dots you can see...
you can find these kinds of metrics in human-interface design references.
So choose between pretty pictures and information content.  You can have
both if you want.  

>>After all... most of the REAL NICE TV sets with REAL NICE pictures are only
>>about 500+ vertical lines....  
>>Why do they look so nice then compared to my computer?
>>   You ask...
>
>>Good question....  Its because the TV is displaying an analog representaion
>>of the actual image... an image which in 'computer terms' is 24 bit, or 16.7
>>million colors....  If you just stay at 640x480 res and jump from 256 colors
>>to 32K, the improvement is incredible... much better than going to 1280x1024.
>
>This is not true. Television sets have something called anti-aliasing which 
>the low-end to medium-end graphics boards (VGA to SuperVGA) do not have. 

This is a minor nit, but televisions do not have an anti-aliasing circuit
built in.  The anti-aliasing effect is a byproduct of the analog (or at
least high S/N ratio) sampling of the cameras involved.  Incidentally, there
are some medium-end products such as ATI's Graphic Ultra series which have
anti-aliasing capabilities...whether this is clever hardware or clever
drivers I can not say.  They call it their "CrystalFonts" technology.  There
was also the ill-fated CEG chip, which was supposed to provide amazing
improvements in apparent resolution without making a sacrifice in memory
requirements...wonder what happened to it.  I heard it was tough to program.

>[SNIP]
>In many cases, professional graphics are rendered in 
>24-bit (16M colors) and then converted to 8-bit (256 colors) with good 
>conversion programs which keep the resolution and the graphic quality, while 
>reducing the generating time and disk space.

Hmmm...rendering in 24-bit color then quantizing to 8-bit indexed color
would not reduce the generating time or the storage spac...you've still
got to calculate and store those gigantic frames.  After you have the
frame all done, you can quantize it and then reap savings benefits.
-- 
Dave Seah ^..^   | Graduate MSEE, University of Rochester, New York           |
                 | Apple II Graphics & Sound Forum Consultant, America Online |

[Internet] seah@ee.rochester.edu, AFCDaveS@aol.com   [America Online] AFC DaveS
Newsgroups: alt.cyberpunk.tech