Path: utzoo!utgpu!attcan!uunet!lll-winken!lll-lcc!ames!think!bloom-beacon!apple!vsi1!octopus!avsd!childers
From: childers@avsd.UUCP (Richard Childers)
Newsgroups: comp.graphics
Subject: Re: the word "bitmap"
Message-ID: <375@avsd.UUCP>
Date: 6 Jan 89 06:57:18 GMT
References: <8568@pasteur.Berkeley.EDU>
Reply-To: childers@avsd.UUCP (Richard Childers)
Organization: die Edelstahlratte
Lines: 49

In article <8568@pasteur.Berkeley.EDU> ph@miro.Berkeley.EDU (Paul Heckbert) writes:

>I've been troubled lately to see people using the word "bitmap" to mean
>a grayscale or color image.  As long as I can remember, however, "bitmap"
>has meant a ONE BIT PER PIXEL, black and white image.

I would think the word is actually a compound word :

	bit - the smallest *meaningful* quanta in the data set referred to

	map - a set of data internally relevant, presumed to be relevant to
		external reality as well

	bitmap - a set of data using the 'bit' as the smallest unit of data

>Where is this new, (and I believe) incorrect usage coming from?

Computer scientists, I guess.		(-:

>Several contributors to this news group have used "bitmap" as a synonym for
>"image" yet I don't think I've ever seen that usage in a book, journal article,
>or software documentation.

You'd prefer 'bytemap' ?  Do we need to confuse everyone all over again ?

>I hope the new usage doesn't catch on, because the old, correct meaning of
>"bitmap" fills a niche, and the new meaning is redundant (we don't need
>another synonym for "image" and "picture").  If you see people misusing the
>word "bitmap", correct them!

Since the meaning will continue to be extracted by a bit-by-bit analysis of
the data set - admittedly, the bits are now interpreted as groups, but that,
too, is in flux, as the size of color tables increases - I think 'bitmap'
is appropriate.

If you're correct, however, then even using it to refer to a grayscale image
is incorrect.

>Paul Heckbert, CS grad student
>508-7 Evans Hall, UC Berkeley		UUCP: ucbvax!miro.berkeley.edu!ph

-- richard


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