[Coco] The myth of the Coco3 256 color mode :)

[Joel Ewy]

On 04/16/2013 04:49 PM, Stephen H. Fischer wrote:
>
> ----- Original Message ----- From: "Joel Ewy" <jcewy at swbell.net>
> To: "CoCoList for Color Computer Enthusiasts" <coco at maltedmedia.com>
> Sent: Tuesday, April 16, 2013 8:56 AM
> Subject: Re: [Coco] The myth of the Coco3 256 color mode :)
>
>
> Though the
>>> conversion process resulted in pretty crummy video, the color 
>>> artifacting worked like a charm, and the colors come out looking 
>>> pretty much the same as they do on a monitor: 
>>> http://www.youtube.com/watch?v=hjcUdoW0rrg
>>>
>> FWIW, I think the above URL might be an abridged version of the 
>> slideshow. Not sure what that's about.  The whole thing seems to be 
>> here: 
>> http://www.youtube.com/watch?feature=player_detailpage&v=hjcUdoW0rrg
>>
>> JCE
>
> If it has been shortened, thanks.
>
> It was like watching a friends vacation slides without your glasses 
> and wanting to go home.
>
> SHF
>

Sorry if you found the subject matter boring and the resolution low, 
Stephen.  I chose photos that were Creative Commons licensed, so I could 
legally include them in a derivative work, and that would demonstrate 
what digital photos would look like using this method of display.  I 
tried to pick a variety of subjects.  I wanted to show people, both 
close up and at a little distance.  I wanted to show things that one 
might see in an adventure game.  I also included one picture that was 
not a photo but a computer generated graphic.

Personally, watching the slideshow again, I am surprised at how good the 
images look, aside from the messiness of the video capture.  Use 'view' 
in NitrOS-9 to display a 256 color .gif and tell me how you think it 
looks compared to the images I put in that slideshow. Remember, this is 
an unmodified CoCo 3, and this uses no palette switching or screen 
flipping, so it can be used in games, or anywhere else you can display a 
640x200x4 image, as long as you have a composite monitor or TV.  The 
effective resolution is low: 160x200.  But the added colors can make it 
well worth the trade-off for some purposes.  If you want to see the best 
quality representation of a digital photo the CoCo 3 can produce, try 
Sockmaster's Hi-color program.  It's fantastic, though it still does 
have a little glitchiness when the palette registers are updated, and 
some flicker, though much less than most.  The problem is, that doesn't 
work in OS-9, and it doesn't work as a slideshow, and it can't easily be 
used inside other programs.

One thing I've been playing with is the possibility of making a hybrid 
image that superimposes high detail areas as a 4 gray 640x200 image on 
top of the 160x200 artifact color image.  I remember from CoCo Max that 
while you might get some unwanted artifacts (color error), you could 
still put a lot of detail in a 256x192 image by treating it as a 
full-resolution B/W bitmap, but use the red/blue artifacts to add color 
in larger areas.  From what I understand, the human eye is more 
sensitive to shades of gray than color, so rendering areas of detail in 
gray should make for a more recognizable image, even if there are some 
unwanted color artifacts.  My initial experiments are promising, but I 
don't have anything to show quite yet.

JCE

>
>
>
> -- 
> Coco mailing list
> Coco at maltedmedia.com
> http://five.pairlist.net/mailman/listinfo/coco
>