Hello e!

> I really really need advice on creating thumbnails.  

> http://www.netcom.ca/~enigma/INDEX.html    

> can use with paintshop pro? Currently I am scanning at 200dpi and
> reducing the image size using the RESIZE option.  Also, is .gif or
> .jpg generally better for thumbnails?  

'Thumbnail' is irrelevant regarding GIF or JPG. These are 'photoreal' 
images and call for JPG.

The problem with thumbnailing is that -so- much information is just 
plain lost in resizing, regardless of image format. Example, self.jpg 
is 250x361 = 90250 pixels. The thumbnail is 50x72 = 3600 pixels, appx 
4% of the original. A thumbnail will look 'similar' to the full size 
image, but no way can it really look 'the same but smaller'.

Here's a 'for instance' a speck of 'red' against 'white':

WWWWW
WWWWW
WWRWW
WWWWW
WWWWW

Shrink that by 25x and you're left with:

W

...and the bit of red is lost.

Here's one way to retain 'some' of what's lost, two steps, blur 
slightly then resize. Using the above example, some of the 'red' is 
blurred outward into the white area:


WWWWW
WRRRW
WRRRW
WRRRW
WWWWW

Then after resizing:

R

...and that speck of red is retained.

In JPG every little bit of color that gives the 'impression' of 
'something' helps a lot, yields a 'better' picture.

I don't take credit for that trick, I read it somewhere, probably a 
long time ago in an HWG list.

Have a :) day!

jim barchuk
mailto:jb(at)jbarchuk.com
http://www.jbarchuk.com

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