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TIFF and LibTiff Mail List Archive

Thread

1999.07.15 23:47 "RGB Gradient Code, adapted from Andreas Neumann", by Eric B. Middlecamp
1999.07.16 06:23 "Re: RGB Gradient Code, adapted from Andreas Neumann", by Niles Ritter
1999.07.16 16:08 "Re: RGB Gradient Code, adapted from Andreas Neumann", by Eric B. Middlecamp
1999.07.16 16:17 "Re: RGB Gradient Code, adapted from Andreas Neumann", by Daniel McCoy
1999.07.16 17:39 "Re: RGB Gradient Code, adapted from Andreas Neumann", by Eric B. Middlecamp
1999.07.16 20:04 "Re: RGB Gradient Code, adapted from Andreas Neumann", by Phillip Crews

1999.07.16 16:08 "Re: RGB Gradient Code, adapted from Andreas Neumann", by Eric B. Middlecamp

Niles Ritter <ritter@earthlink.net> on 07/16/99 01:23:55 AM

To:
cc: TIFF Mailing List <tiff@olympiakos.com> (bcc: Eric B.
      Middlecamp/MIPP/Imation)

Subject:Re: RGB Gradient Code, adapted from Andreas Neumann

I made a simple extension to Andreas Neumann's gradient code, (see

http://www.gis.univie.ac.at/strv/strv/leute/andi/computer/graphics/raster-formats/example_tiff_main.html

)

but the output TIFF image has some odd contamination. Looking at the image, you wouldn't be able to tell -- however a histogram reveals that some levels are omitted and others are doubled.

Has anyone else experienced bizarre anomalies like this?

No.

I just ran your little routine, and got a perfect 0-255 vertical gradient. Are you sure your monitor is on true 24-bit color and not 16-bit or 8-bit? Try running "tiffinfo -d" on your image to look at the values.

Niles,

My monitor depth is set to millions of colors. Note that the results I get _look_ correct, but

I found anomalies when I used Photoshop to display the histogram. Note that I am running on

a Mac, so the problems might be system-dependent.

I'll try using tiffinfo-

Thanks,

Eric Middlecamp