LibTiff Mailing List
TIFF and LibTiff Mailing List Archive
February 2011
Previous Thread
Next Thread
Previous by Thread
Next by Thread
Previous by Date
Next by Date
Contact
The TIFF Mailing List Homepage
This list is run by Frank Warmerdam
Archive maintained by AWare Systems
Thread
2011.02.10 16:49 "Re: ImageDepth tag", by Frank Warmerdam
On 11-02-10 11:33 AM, John Evans wrote: > Hello, I was wondering what people's experiences are with the ImageDepth tag. > There are a few mentions of it on this mailing list if one goes back far > enough, but every TIFF I've seen so far (that has actually had the ImageDepth > tag set) has had ImageDepth trivially set to 1, such as "cramps-tile.tif". > Every TIFF except for one, that is. That particular TIFF was pretty simple > otherwise, photometric interpretation of MINISBLACK, SamplesPerPixel = 1, > ImageDepth = 16. > > I can see how the ImageDepth tag could be useful, i.e. just one IFD with > thousands of slices vs. thousands of IFDs each with just one slice. And I > can create TIFFs with with ImageDepth> 1 in other photometric > interpretations, such as RGB and YCbCr... but do people ever actually run > into such beasts? John, I have not encountered TIFF files with non-trivial image depth values. I doubt there is much client software ready for them. I'm not even convinced that libtiff handles them well. In *theory* I can see some utility for ImageDepth, but in practice I would prefer to just avoid promoting it's use. Best regards, -- ---------------------------------------+-------------------------------------- I set the clouds in motion - turn up | Frank Warmerdam, warmerdam@pobox.com light and sound - activate the windows | http://pobox.com/~warmerdam and watch the world go round - Rush | Geospatial Programmer for Rent