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2010.06.22 19:29 "Re: Tiff Digest, Vol 73, Issue 14", by James Morgenstern
Slow down -- you are confusing two different concepts: number of channels and number of bits per channel. If you have 3 channels of 8 bit data then using the RGB function to read and display using 3 color mapping. But if you have 1 channel of 32 bit data [I assume this is integer and not float?] then you need a display device that is capable of 2^32 different gray levels OR you need to transform the data to map the 32 bits down to say 8 bits. [or 16 bits]. So read a line of data and then transform each data entry: dataout[i] = (data[i] + offset) / gain; To restate: your problem is to match the dynamic range of the display device to the dynamic range of the data. Can you histogram the data to get a sense of what offset and gain you should use? -----Original Message----- From: tiff-bounces@lists.maptools.org [mailto:tiff-bounces@lists.maptools.org] On Behalf Of tiff-request@lists.maptools.org Sent: Tuesday, June 22, 2010 1:00 PM To: tiff@lists.maptools.org Subject: Tiff Digest, Vol 73, Issue 14 Send Tiff mailing list submissions to tiff@lists.maptools.org To subscribe or unsubscribe via the World Wide Web, visit http://lists.maptools.org/mailman/listinfo/tiff or, via email, send a message with subject or body 'help' to tiff-request@lists.maptools.org You can reach the person managing the list at tiff-owner@lists.maptools.org When replying, please edit your Subject line so it is more specific than "Re: Contents of Tiff digest..."