Re: LONG AND NARROW IMAGE

[davidf(at)dfanning.com (David Fanning)]

Mark Chan (chanm@cadvision.com) writes:

> Given:
> 1 cm by 100 cm long continuous color photo (actual size). Saved in an image
> format readable by IDL (e.g. READ_JPEG or equivalent). Cannot reduce in size
> otherwise details will be lost.

Uh, what size is it? In pixels, not centimeters. Did you scan it?
What resolution did you scan it at? Is it a 24-bit image or an
8-bit image?
 
> Want:
> Read into IDL. Display only 3 cm strip of the actual photo at any given
> time. Which portion to show depends on some other parameter output from
> another routine.

How many pixels does your monitor support per pixel? 
How many pixels is your image, etc. 

> Problem:
> 1) Does any one have a similar code to share? If not, any web site that I
> can get some idea on how best to do this? Any suggestion, especially on the
> logic, is greatly appreciated.

On logic!? No, I'm not going to touch it.  :-)
 
> 2) I got a very grainy image when the image is displayed inside IDL. The
> same image is very clear when displayed using a graphical package (e.g.
> PhotoShop or equivalent). This is the first time for me on such topic. I
> must be doing something wrong. Running IDL on WinNT4. Could it be color
> indexing problem? Or resolution problem, etc? Want to improve quality of
> image in IDL. Suggestions?

Was it a JPEG image? Did it have a color table with it?
Did you load it? When you say "grainy", do you mean the
colors didn't appear right, or that the pixels were
grainy? What IDL command did you use to display it?
Did you try to resize it?

I'm still pretty much in the dark here. :-(

Cheers,

David

-- 
David Fanning, Ph.D.
Fanning Software Consulting
Phone: 970-221-0438 E-Mail: davidf@dfanning.com
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