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TIFF and LibTiff Mail List Archive

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1994.10.24 11:43 "Pipeable Tiff and Colormaps", by Spencer Johnson
1994.10.24 15:34 "Re: Pipeable Tiff and Colormaps", by Sam Leffler

1994.10.24 11:43 "Pipeable Tiff and Colormaps", by Spencer Johnson

Pipeable TIFF -

I am looking for the ability to generate "pipeable" tiff stream files. Does anyone know of any effort going on in this area? I envision "pipeable" tiff files as having all non-image data fields prior to image data fields. That way when the image data is read from the stream, one knows how to interpret it without loading the entire image into memory. With such files, utilities can be piped together to process imagery concurrently.

Colormaps -

The TIFF 6.0 specification requires colormaps for palette files, but does not specifically exclude them for other photometric interpretations. Also Sam Leffler's fabulous software allows ( at least version 2.4 allows ) colormaps for grayscale images.

My questions are:

  1. Are colormaps valid for grayscale files and files of other photometric interpretations? If so, is the scanline indexes into the colormaps as it is for palette files? Why don't such files have a photometric interpretation of palette?
  2. Do people actually use such files or are they simply obsolete forms of TIFF files.

Thanks

Spencer Johnson email: spencer@kodak.com
                phone: (716) 253-5551