TIFF and LibTiff Mail List Archive

# 2007.12.10 06:21 "Re: [Tiff] dpi settings", by Toby Thain

On 10-Dec-07, at 2:42 AM, Ron Croonenberg wrote:

Sorry, perhaps I overstated it (the centimetre-gram-second system is deprecated), but there has certainly been some movement away from centi as a preferred prefix.

Neah, I think it is still in fashion.

btw, the seconds (minute etc) system isn't metric. metric is base 10, time and degrees are base 60. That's from the old Greek era. The greek thought there was something special with the numbers 3,4 and 5 (remember that triangle thingy ?) 3*4*5 happens to be 60

It may go back to the Greeks, but the reason why the Imperial system commonly uses highly factorisable numbers (12, 24, 60, ...) is clearly convenience of division into parts, when arithmetic is done mentally or manually. Other ancient systems also used bases such as 60.

In these days of rocket science the virtues of the Metric system are more apparent (did Imperial or Metric man land on the moon? it would be interesting to know what Apollo engineers used).

I understand the metrication authority is largely disbanded, as their primary task is done.

true, almost everyone uses it now. (except for the US and English system and some isolated tribe that was discovered a good while ago. They use a base 20 system.) It happens that no system in use is really 'pure'. Look at the way we count. It is considered base 10, however we still use base 20 system 'remnants' for counting in language. When counting from 10 till 20 we don't say '10 1' '10 2' '10 3'... however after 20 we do.

That's language, not measurement... which has its own quirks. Not even all European languages are consistent in it.

For purposes of resolution, I doubt it. Do you find inches more practical in this connection?

Inches aren't used much, except in translating US based standards and documents. If you were to ask anyone aged 30 or less what an inch is, or how many inches in a foot, they probably couldn't give you a confident answer.

to me it doesn't really matter what is used, as long as it is clear what system is used. I'm a 'hybrid', and am used to both Although 1.7 inches still sounds funny to me. (I just flip my ruler back and forth when that happens)

ok, back to tiff... does anyone know of a simple routine to read a tiff file so that I can stick the pixel colors in a 2D matrix?

Ah, a good old FAQ.

--Toby

thanks,

Ron

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