From 42098725cc6d9484c2d8b5c0427f38754c0a17c8 Mon Sep 17 00:00:00 2001 From: giraffedata Date: Fri, 20 Apr 2018 19:47:23 +0000 Subject: miscellaneous update git-svn-id: http://svn.code.sf.net/p/netpbm/code/userguide@3205 9d0c8265-081b-0410-96cb-a4ca84ce46f8 --- pamlevels.html | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) (limited to 'pamlevels.html') diff --git a/pamlevels.html b/pamlevels.html index 6f3c4db3..15e85176 100644 --- a/pamlevels.html +++ b/pamlevels.html @@ -2,7 +2,7 @@ Pamlevels User Manual

pamlevels

-Updated: 08 April 2018 +Updated: 10 April 2018
Table Of Contents @@ -38,17 +38,16 @@ color-mapping options may be shortened to -f1...-f3 and -t1...-t3.

Color values have the following format: -color[:scale], where color is -a Netpbm color specification -and scale an optional coefficient that is applied to each component -of color. - -

The transformation preserves -color integrity. +color[:scale], where color is a + Netpbm color specification and +scale an optional coefficient that is applied to each RGB component (in +the standard Netpbm gamma-adjusted color space) of color.

When the transformation is linear (i.e. uses two mappings) and preserves zero (i.e. maps black to black), it corresponds to multiplication of light -intensity by a constant. +intensity by a constant and preserves +color integrity. +

EXAMPLES

In the examples below, \ denotes a line continuation: @@ -70,7 +69,7 @@ pamlevels -f1 black -t1 black\ 
pamlevels \
 -f1 black -t1 black -f2 white -t2 white \
 -f3 white:0.5 -t3 white:0.6 in.ppm > out.ppm
-The latter tranformation similar to gamma-correction. +The latter tranformation is similar to gamma-correction.

OPTIONS

@@ -93,8 +92,9 @@ variation on PPM where the samples are proportional to light intensity, rather than brightness (gamma-adjusted) as in true PPM. The input must be of this form and the pamlevels makes the output of this form. -

Note that the numbers in a rgbi: color specification are brightness -levels (gamma-adjusted) regardless of the input and output format. +

Note that the numbers in a color specification like +rgbi:0.9/0.83/0.80 are brightness levels (gamma-adjusted) regardless of +the input and output format.

You cannot use this with -fitbrightness because that function is not implemented. -- cgit 1.4.1