AWARE SYSTEMS
TIFF and LibTiff Mail List Archive

Thread

1999.06.03 19:48 "Large File Support", by Bruce Forsberg
[...]
1999.06.14 14:58 "Re: Large File Support", by Tom Lane
1999.06.14 15:30 "Re: Large File Support", by Eric Shapiro
1999.06.14 16:27 "Re: Large File Support", by Chris Barker
1999.06.14 15:51 "Re: Large File Support", by Martin Bailey
[...]

1999.06.14 15:30 "Re: Large File Support", by Eric Shapiro

I agree with that goal, but I think that Frank Warmerdam's idea (allow multiple separate TIFF files to be logically "tiled" together to form a huge image) is a more practical approach, for the reasons already mentioned by him and John Aldridge.

One nice thing that Apple did with QuickTime was that if a user opened a compressed PICT file on a system without QuickTime, the image displayed was a message suggesting that the user install QuickTime.

You can do this with your "control" file -- put an actual 1 bpp TIFF image in it with the message "This file requires a newer TIFF viewer".

Splitting a single image into multiple files is a kludge, but it does have the added plus of working with operating systems that don't support large (> 2GB) files yet.

But, in the long run, a real 64-bit image file format is probably needed. Would the current compressors (LZW, JPEG, etc) scale to 64-bit images, though? That is, can you even compress a > 2GB image using the standard JPEG library?

-Eric

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 Eric Shapiro                   eric@relium.com
 Relium Corp.                    www.relium.com
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