2003.11.19 00:30 "[Tiff] tiff2pdf contribution", by Chris Hanson

I'm trying to figure out what to do about the TIFF orientation tag.

You could probably use the orientation tag to change the CTM used to actually perform drawing. That way you don't have to actually transcode any data.

So for instance, the CTM for an image with ORIENTATION_BOTLEFT would be [1 0 0 1 0 0] (the identity transform) but the CTM for an image with ORIENTATION_TOPLEFT would be [1 0 0 -1 0 0].

For the benefit of those outside the PostScript/PDF universe, [a b c d e f] is how we write the transformation matrix

     [ a b 0
       c d 0
       e f 1 ]

It should be possible to just use the orientation tag to manipulate the CTM so you don't have to change any of the TIFF image data.

-- Chris

Chris Hanson <cmh@bdistributed.com>
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