AWARE SYSTEMS
TIFF and LibTiff Mail List Archive

Thread

2003.12.03 06:20 "[Tiff] Double Precision TIFF images", by Chris Cox
2003.12.03 18:40 "[Tiff] Double Precision TIFF images", by Frank Warmerdam
2003.12.04 21:11 "[Tiff] Double Precision TIFF images", by Antonio Scuri
2003.12.04 21:22 "[Tiff] Double Precision TIFF images", by Frank Warmerdam
2003.12.05 21:23 "[Tiff] Double Precision TIFF images", by Chris Cox
2003.12.05 04:18 "[Tiff] Double Precision TIFF images", by Chris Cox
2004.01.23 20:30 "Re: [Tiff] How to convert MINISBLACK to PHOTOMETRIC_RGB", by Bob Friesenhahn
2004.01.23 17:16 "Re: [Tiff] How to convert MINISBLACK to PHOTOMETRIC_RGB", by Joris
2004.01.23 17:38 "Re: [Tiff] How to convert MINISBLACK to PHOTOMETRIC_RGB", by Frank Warmerdam
2004.01.23 19:15 "Re: [Tiff] How to convert MINISBLACK to PHOTOMETRIC_RGB", by Bob Friesenhahn
2004.01.23 20:17 "Re: [Tiff] How to convert MINISBLACK to PHOTOMETRIC_RGB", by Andy Cave
2004.01.23 17:57 "Re: [Tiff] How to convert MINISBLACK to PHOTOMETRIC_RGB", by Joris
2004.01.23 18:55 "Re: [Tiff] How to convert MINISBLACK to PHOTOMETRIC_RGB", by Frank Warmerdam
2004.01.23 19:15 "Re: [Tiff] How to convert MINISBLACK to PHOTOMETRIC_RGB", by Joris
2004.01.23 19:19 "Re: [Tiff] How to convert MINISBLACK to PHOTOMETRIC_RGB", by Bob Friesenhahn
2004.01.23 19:24 "Re: [Tiff] How to convert MINISBLACK to PHOTOMETRIC_RGB", by Frank Warmerdam
2004.01.23 20:12 "Re: [Tiff] How to convert MINISBLACK to PHOTOMETRIC_RGB", by Chris Cox
2004.01.23 20:52 "Re: [Tiff] How to convert MINISBLACK to PHOTOMETRIC_RGB", by Chris Cox

2004.01.23 20:17 "Re: [Tiff] How to convert MINISBLACK to PHOTOMETRIC_RGB", by Andy Cave

Hi Joris.

Any chance you could mail me the file in question. I'd like to see how our TIFF viewer copes with it.

Thanks,

Andy.

----- Original Message -----

> > Frank Warmerdam wrote:
> >

> >
> >

> > Thanks Frank. Now I know I finally did understand it correctly. Am I also

> > correct in thinking that the only proper way ignorant software (as in > > software that doesn't know about how the image came about or what it is

> > intended to contain) can correctly interpret this 3-channel image as a > > grayscale image with 2 extra channels that have no specified

> > application/meaning? If ignorant software were to have to render this image,

> > the correct thing to do is to render the first channel as grayscale, and > > discard the others as far as rendering is concerned, is that right? I

> > realize this may also be trivial questions, but this thread is very

> > confusing.
>
> Joris,
>
> I am by no means an authority on the TIFF specification. My
interpretation

> of the file in question is that a sensible application should render the > first band in greyscale and ignore the 2nd and 3rd since they are extra samples

> with no meaning attached. Without the ExtraSamples tag, I think an application

> should assume the file contains 3 greyscale bands which might be drawn in any

> number of ways. One way would be to draw 1 band, and give the user the
ability
> to flip through to see the 2nd and 3rd. Another would be to just treat
them
> as RGB (as many multispetral imaging packages will do with the first 3
bands
> of multispectral data).
>

> A viewing application that only showed the first band as greyscale with no > options to inspect the others would be acceptable and reasonable, but that

> viewer would have little utility in the rather small work of multispectral > image processing (IMHO).

> ---------------------------------------+----------------------------------
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