AWARE SYSTEMS
TIFF and LibTiff Mail List Archive

Thread

2002.08.15 00:33 "Orientation field", by Dante Allegria
2002.08.15 00:52 "Re: Orientation field", by Jon Saxton
2002.08.15 01:13 "Re: Orientation field", by Dante Allegria
2002.08.15 13:12 "RE: Orientation field", by Kari Poysa
2002.08.15 14:21 "RE: Orientation field", by Peter Nielsen
2002.08.15 16:34 "Re: Orientation field", by Daniel McCoy
2002.08.15 17:14 "RE: Orientation field", by Jeff Urlwin
2002.08.16 07:23 "Re: Orientation field", by Andreas R. Kleinert
2002.08.16 12:11 "Re: Orientation field", by Peter Nielsen
2002.08.16 14:15 "Re: Orientation field", by Kevin D. Quitt
2002.08.16 14:34 "RE: Orientation field", by Kari Poysa

2002.08.16 07:23 "Re: Orientation field", by Andreas R. Kleinert

Mind you, not supporting the orientation tag is pure laziness. For the writer

As - in most cases - also is writing images bottom-up.
That is: lazyness.

Some points to consider:

1. If there's not much code involved, why write bottom-up anyway?

a) Because the corresponding device does it this way.

If so: why does it *and* why should this image be destined for display by an image viewer then, in the first place?

Examples: Scanners. But you always could flip the original,

          before scanning.

b) Because the used frame-buffer is organized this way.

If so: if it's a random-access memory, a bit of arithmetics

       (basically the same as for a flip-operation but without
       the need for extra memory) will help.

Examples: a bottom-up frame buffer memory (simply read from

          'native' bottom-right to upper-left and flip it this way)

2. If memory consumption is not an issue, why not flip on/after the source
   instead of inside the TIFF viewer?

a) Because it's a different kind of device with different restrictions.

But why not at least write as many "strips" as there are "rows", with a "rows per strip" of one and then re-arrange (sort) the strips? (i.e. the offsets of the strips)

b) Because those TIFFs can be upto 4 GB (etc.)

Well, too large for PCs, either. See a)

3. Where's the problem in batch-converting a bunch of wrongly oriented
   images right after creation?

...

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