1993.10.19 15:40 "Re: Multi-spectral, Tiled, Compressed TIFF images", by Sam Leffler

A project that we are working on produces the following type of image which we would like to store using TIFF. The image consists of 7 separate bands (eg: 3 visible wavelengths and four IR wavelengths) which can be stored on separate pages within one TIFF file. Each band has 16-bit pixels. Each band is about 10k pixels wide by 20k pixels high, which we wish to process as 200 1k x 1k tiles. Also, the image will contain some very large regions of black-fill (pixel value = 0), which we would like to remove with some form of compression. The compression must be loss-less, since it is mandatory to maintain the integrity of the pixel intensity.

> From my reading of the TIFF 6.0 doc, it appears that each of the above criteria can be met with TIFF, but it is not clear if they can all be met at the same time. In effect, what I am looking for is to use TIFF to store a:

        multispectral, tiled, compressed image

such that TIFF readers which are compliant with version 6.0 extensions can access the imagery.

Yes, you can store this sort of data in TIFF. If you want to store more than 4 channels of data then you'll need the v3.3beta code since until then the library had a restriction that no more than 4 channels could be stored.

Also, will the SGI ImageVision library tools be able to store/retrieve files of the kind described above?

It should, but you should check with those folks directly. I believe that most IL users with this sort of data use another format that's more commonly found in the image processing community. I don't recall if that format has compression though.

Sam