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-rw-r--r-- | pambrighten.html | 160 | ||||
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-rw-r--r-- | ppmwheel.html | 42 |
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diff --git a/directory.html b/directory.html index 26e3eeac..c81a7f39 100644 --- a/directory.html +++ b/directory.html @@ -765,7 +765,7 @@ a color map containing all possible colors of given maxval <DT><B><a href=pamfunc.html>pamfunc</a></B> <DD>apply simple arithmetic function to samples in an image -<DT><B><a href=ppmbrighten.html>ppmbrighten</a> </B> +<DT><B><a href=pambrighten.html>pambrighten</a> </B> <DD>brighten or dim an image -- change saturation and value <DT><B><a href=ppmflash.html>ppmflash</a></B> diff --git a/pambrighten.html b/pambrighten.html new file mode 100644 index 00000000..14102cd0 --- /dev/null +++ b/pambrighten.html @@ -0,0 +1,160 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 3.2//EN"> +<HTML><HEAD><TITLE>Pambrighten User Manual</TITLE></HEAD> +<BODY> +<H1>pambrighten</H1> +Updated: 12 January 2019 +<BR> +<A HREF="#index">Table Of Contents</A> + +<H2>NAME</H2> +pambrighten - change a PPM image's Saturation and Value + +<H2 id="synopsis">SYNOPSIS</H2> + +<b>pambrighten</b> +[<b>-saturation=</b>[<b>+</b>|<b>-</b><i>saturation_percent</i>]] +[<b>-value=</b>[<b>+</b>|<b>-</b><i>value_percent</i>]] +<i>netpbmfile</i> + +<P>Minimum unique abbreviation of option is acceptable. You may use +double hyphens instead of single hyphen to denote options. You may use +white space in place of the equals sign to separate an option name +from its value. + +<H2 id="description">DESCRIPTION</H2> + +<p>This program is part of <a href="index.html">Netpbm</a>. + +<p><b>pambrighten</b> increases or decreases the Saturation and Value +(from the HSV color space) of each pixel of a Netpbm image. You specify +the percentage change for each of those parameters. + +<p>You can also remap the colors of the pixels so their Values cover the full +range of possible Values. + +<p>The output format is the same as the input format and any extra channels, +such as transparency, are passed through. + +<p>Hue-Saturation-Value, or HSV, is one way to represent a color, like the +more well-known RGB. Hue, Saturation, and Value are numbers in the range from +0 to 1. We always capitalize them in this document when we mean the number +from the HSV color space, especially since "value" as a conventional English +word has a much more abstract meaning. + +<p>Value is a measure of how bright the color is, relative to some specified +maximum (the Netpbm formats are also defined in terms of a specified maximum +brightness -- For the purposes of this program, they are the same). In +particular, it is the brightness of the brightest primary color component of +the color divided by the maximum brightness possible for a component. Zero +Value means black. White has full Value. + +<p>Hue is an indication of the secondary color with the same brightness that +most closely approximates the color. A secondary color is made of a +combination of at most two of the primary colors. + +<p>Saturation is a measure of how close the color is to the color indicated by +the Hue and Value. A lower number means more light of the third primary color +must be added to get the exact color. Full Saturation means the color is a +secondary color. Zero Saturation means the color is gray (or black or white). +Decreasing the saturation of a color tends to make it washed out. + +<p>If it is impossible to increase the Value of a pixel by the amount you +specify (e.g. the Value is .5 and you specify +200%), <b>pambrighten</b> +increases it to full Value instead. + +<p>If it is impossible to increase the Saturation of a pixel by the amount +you specify (e.g. it is already half saturated and you specify +200%), +<b>pambrighten</b> increases it to full Saturation instead. + +<p>For a simpler kind of brightening, you can use <b>pamfunc -multiplier</b> +simply to increase the brightness of each pixel by a specified percentage, +clipping each RGB component where the calculated brightness would exceed full +brightness. Thus, the brightest colors in the image would change chromaticity +in addition to not getting the specified brightness boost. For +<em>decreasing</em> brightness, <b>pamfunc</b> should do the same thing as +<b>pambrighten</b>. + +<p><b>ppmflash</b> does another kind of brightening. It changes the color of +each pixel to bring it a specified percentage closer to white. This increases +the value and saturation. + +<p><b>pambrighten</b> is the same as <b>pambrighten</b>, except that it +recognizes the various Netpbm image formats rather than treating them all as +PPM. The output format is the same as the input format and extra channels in +a PAM image (such as a transparency channel) get passed through. + +<p>If you want to modify the Hues in the image, use <b>pamhue</b>. + + +<H2 id="examples">EXAMPLES</H2> +<p>To double the Value of each pixel: +<pre> +pambrighten -value=100 +</pre> + +<p>To double the Saturation and halve the Value of each pixel: +<pre> +pambrighten -saturation=+100 -value=-50 +</pre> + +<H2 id="options">OPTIONS</H2> + +<DL> +<DT><b>-value=</b><i>value_percent</i> + +<DD>This option specifies the amount, as a percentage, by which you want to +change the Value of each pixel. It may be negative. + +<DT><b>-saturation=</b><i>value_percent</i> + +<DD>This option specifies the amount, as a percentage, by which you want to +change the Saturation of each pixel. It may be negative. + +</DL> + +<H2 id="seealso">SEE ALSO</H2> + +<A HREF="pnmnorm.html">pnmnorm</A>, +<A HREF="ppmdim.html">ppmdim</A>, +<A HREF="pamfunc.html">pamfunc</A>, +<A HREF="ppmflash.html">ppmflash</A>, +<A HREF="pamaltsat.html">pamaltsat</A>, +<A HREF="pmbrighten.html">ppmbrighten</A>, +<A HREF="pamdepth.html">pamdepth</A>, +<A HREF="pnmgamma.html">pnmgamma</A>, +<A HREF="pamhue.html">pamhue</A>, +<A HREF="ppmhist.html">ppmhist</A>, +<A HREF="ppm.html">ppm</A> + +<H2 id="history">HISTORY</H2> + +<P><B>pambrighten</B> was new in Netphm 10.86 (March 2019). It was a +PAM conversion of the much older <b>ppmbrighten</b>. + + +<H2 id="author">AUTHOR</H2> + +<p>Copyright (C) 1990 by Brian Moffet. +Copyright (C) 1989 by Jef Poskanzer. + +<P> +Permission to use, copy, modify, and distribute this software and its +documentation for any purpose and without fee is hereby granted, provided +that the above copyright notice appear in all copies and that both that +copyright notice and this permission notice appear in supporting +documentation. This software is provided "as is" without express or +implied warranty. + +<HR> +<H2 id="index">Table Of Contents</H2> +<UL> +<LI><A HREF="#synopsis">SYNOPSIS</A> +<LI><A HREF="#description">DESCRIPTION</A> +<LI><A HREF="#examples">EXAMPLES</A> +<LI><A HREF="#options">OPTIONS</A> +<LI><A HREF="#seealso">SEE ALSO</A> +<LI><A HREF="#history">HISTORY</A> +<LI><A HREF="#author">AUTHOR</A> +</UL> +</BODY> +</HTML> diff --git a/ppmbrighten.html b/ppmbrighten.html index b2e450ac..7229bd64 100644 --- a/ppmbrighten.html +++ b/ppmbrighten.html @@ -2,7 +2,7 @@ <HTML><HEAD><TITLE>Ppmbrighten User Manual</TITLE></HEAD> <BODY> <H1>ppmbrighten</H1> -Updated: 26 October 2012 +Updated: 12 January 2019 <BR> <A HREF="#index">Table Of Contents</A> @@ -78,6 +78,11 @@ For <em>decreasing</em> brightness, <b>pamfunc</b> should do the same thing as color of each pixel to bring it a specified per centage closer to white. This increases the value and saturation. +<p><b>pambrighten</b> is the same as <b>ppmbrighten</b>, except that it +recognizes the various Netpbm image formats rather than treating them all as +PPM. The output format is the same as the input format and extra channels in +a PAM image (such as a transparency channel) get passed through. + <p>If you want to modify the Hues in the image, use <b>pamhue</b>. @@ -108,10 +113,8 @@ to change the Saturation of each pixel. It may be negative. <DT><b>-normalize</b> -<DD>This option causes <b>ppmbrighten</b> to linearly remap the Values -of the pixels to cover the range 0 to 1. The option name is wrong -- -this operation is not normalization (it was named in error and the -name has been kept for backward compatibility). +<DD>This option causes <b>ppmbrighten</b> to normalize contrast by linearly +remapping the Values of the pixels to cover the range 0 to 1. <p><b>ppmbrighten</b> applies the brightening that you specify with the <b>-value</b> option <em>after</em> the remapping. @@ -128,6 +131,7 @@ with a bogus error message. <A HREF="ppmdim.html">ppmdim</A>, <A HREF="pamfunc.html">pamfunc</A>, <A HREF="ppmflash.html">ppmflash</A>, +<A HREF="ppmflash.html">pambrighten</A>, <A HREF="pamaltsat.html">pamaltsat</A>, <A HREF="pamdepth.html">pamdepth</A>, <A HREF="pnmgamma.html">pnmgamma</A>, diff --git a/ppmwheel.html b/ppmwheel.html index ab23f503..ff62a609 100644 --- a/ppmwheel.html +++ b/ppmwheel.html @@ -2,21 +2,19 @@ <HTML><HEAD><TITLE>Ppmwheel User Manual</TITLE></HEAD> <BODY> <H1>ppmwheel</H1> -Updated: 11 January 2003 +Updated: 13 January 2019 <BR> <A HREF="#index">Table Of Contents</A> -<A NAME="lbAB"> </A> <H2>NAME</H2> ppmwheel - make a PPM image of a color wheel -<A NAME="lbAC"> </A> -<H2>SYNOPSIS</H2> +<H2 id="synopsis">SYNOPSIS</H2> + <B>ppmwheel</B> <I>diameter</I> -<A NAME="lbAD"> </A> -<H2>DESCRIPTION</H2> +<H2 id="description">DESCRIPTION</H2> <p>This program is part of <a href="index.html">Netpbm</a>. @@ -25,48 +23,42 @@ specified diameter inside a white square just large enough to hold it. <p>The color wheel is based on the HSV color model. Hues are distributed angularly around the circle and the values are distributed -radially and the saturation is zero everywhere. The values are zero at +radially and the saturation is 100% everywhere. The values are zero at the center, increasing linearly to maximum at the edge. The maximum value corresponds to the maxval of the PPM image. -<p>Hence, the image contains all of the secondary colors based on the -red, green, and blue primary colors. A secondary color is one that is -composed of light of at most two of the three primary colors. +<p>Hence, the image consists of all of the secondary colors based on the red, +green, and blue primary colors. A secondary color is one that is composed of +light of at most two of the three primary colors. -<A NAME="lbAE"> </A> -<H2>OPTIONS</H2> +<H2 id="options">OPTIONS</H2> <P>None. -<A NAME="seealso"> </A> -<H2>SEE ALSO</H2> +<H2 id="seealso">SEE ALSO</H2> <B><A HREF="ppmcie.html">ppmcie</A></B>, <B><A HREF="ppmrainbow.html">ppmrainbow</A></B>, <B><A HREF="ppm.html">ppm</A></B> -<H2>HISTORY</H2> -<A NAME="history"></a> +<H2 id="history">HISTORY</H2> <P><b>ppmwheel</b> was added to Netpbm in Release 10.14 (March 2003). -<A NAME="lbAH"> </A> -<H2>AUTHOR</H2> +<H2 id="author">AUTHOR</H2> Copyright (C) 1995 by Peter Kirchgessner <HR> -<A NAME="index"> </A> -<H2>Table Of Contents</H2> +<H2 id="index">Table Of Contents</H2> <UL> -<LI><A HREF="#lbAB">NAME</A> -<LI><A HREF="#lbAC">SYNOPSIS</A> -<LI><A HREF="#lbAD">DESCRIPTION</A> -<LI><A HREF="#lbAE">OPTIONS</A> +<LI><A HREF="#synopsis">SYNOPSIS</A> +<LI><A HREF="#description">DESCRIPTION</A> +<LI><A HREF="#options">OPTIONS</A> <LI><A HREF="#seealso">SEE ALSO</A> <LI><A HREF="#history">HISTORY</A> -<LI><A HREF="#lbAH">AUTHOR</A> +<LI><A HREF="#author">AUTHOR</A> </UL> </BODY> </HTML> |