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2002.01.16 11:07 "How to interpret 16-bit GrayScale image?", by Bad Badtz
2002.01.16 14:52 "RE: How to interpret 16-bit GrayScale image?", by Paul Beaty
2002.01.16 16:12 "Re: How to interpret 16-bit GrayScale image?", by Martí_Maria
2002.01.24 05:07 "Re: How to interpret 16-bit GrayScale image?", by Kevin D. Quitt
[...]

2002.01.16 16:12 "Re: How to interpret 16-bit GrayScale image?", by Martí_Maria

Hi,

This means that this grayscale does use 65535 levels of gray to store the image. Note than there are devices, like some printers, that are not limited to 255 or minus of monitors.

You must convert to 8 bits per sample before display. If you don't care about gamma stuff, simply divide each pixel by 257

One can just do a >> 8 to gain speed if don't care roundup, but this is not completly accurate, for example:

    0x2e9 = 745

   745 / 257 = 2.898, rounding = 3
   745 >> 8 = 2

Hope this helps.

Marti Maria.

I have a GeoTIFF image that looks like a grayscale image when viewed with Erdas Imagine. This image has 16 bits per sample and 1 sample per pixel. The photometric interpretation is 1, meaning that it is a grayscale image, and this image has no color table.

How do i interpret the pixel values then? Should I construct an index table with 65536 colors? Are there so many colors? Or can I change the image to RGB colored instead?

Urgent!! Please help!!! Thanks in advance!!

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