2007.12.09 14:05 "Re: [Tiff] dpi settings", by Toby Thain

On 9-Dec-07, at 1:02 AM, Graeme Gill wrote:

TIFFTAG_RESOLUTIONUNIT supports the values RESUNIT_NONE, RESUNIT_INCH, or RESUNIT_CENTIMETER.

Just to make an observation:

It's a pity so many systems are hardcoded with centimetres as the only metric option. Around here they seem to have passed out of popular usage, and mm and Meters are the preferred units. (Nothing to stop applications doing the translation for TIFF files of course!).

A rather nugatory remark, especially given the existence of the RATIONAL type in TIFF. I think around the time of TIFF's conception it was not unusual in Europe to specify pixels per centimetre, which might explain the choice of base unit. But really, does it matter?

--Toby

Graeme Gill.

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