04-18-2008
Quote:
Excuse me for this useless thread
This is not at all useless.
Indeed very helpful and useful for me.
Thanks for this post.
10 More Discussions You Might Find Interesting
1. Programming
Hi all,
I am working in a UNIX/C environment. I would like to understand more about MUTEX and Threads. Can someone explain me these
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Can anyone explain me what mutexes are in
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amit (1 Reply)
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I am trying to use mutex in my multi-tread project, but they don't seem to work.
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#include <stdio.h>
#include <pthread.h>
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{
int val;
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Hi all,
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Hello,
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LEARN ABOUT OPENSOLARIS
ppmtopgm
ppmtopgm(1) General Commands Manual ppmtopgm(1)
NAME
ppmtopgm - convert a portable pixmap into a portable graymap
SYNOPSIS
ppmtopgm [ppmfile]
DESCRIPTION
Reads a portable pixmap as input. Produces a portable graymap as output. The output is a "black and white" rendering of the original
image, as in a black and white photograph. The quantization formula used is .299 r + .587 g + .114 b.
Note that although there is a pgmtoppm program, it is not necessary for simple conversions from pgm to ppm , because any ppm program can
read pgm (and pbm ) files automatically. pgmtoppm is for colorizing a pgm file. Also, see ppmtorgb3 for a different way of converting
color to gray. And ppmdist generates a grayscale image from a color image, but in a way that makes it easy to differentiate the original
colors, not necessarily a way that looks like a black and white photograph.
QUOTE
Cold-hearted orb that rules the night
Removes the colors from our sight
Red is gray, and yellow white
But we decide which is right
And which is a quantization error.
SEE ALSO
pgmtoppm(1),ppmtorgb3(1),rgb3toppm(1),ppmdist(1),ppm(5),pgm(5)
AUTHOR
Copyright (C) 1989 by Jef Poskanzer.
10 April 2000 ppmtopgm(1)