cmap.1

speech signal process tools

.\" Copyright (c) 1989, 1991 Entropic Speech, Inc. All rights reserved.
.\" @(#)cmap.1	1.6 8/4/93	ESI
.TH XCMAP 1\-ESPS 8/4/93
.ds ]W (c) 1992 ERL, Inc.
.SH "NAME"
xcmap \- generate or edit a colormap (X Window version)
.SH "SYNOPSIS"
.B xcmap
.SH "DESCRIPTION"
.PP
.I Xcmap
is an interactive program for generating or modifying
colormaps for use by \fIwaves\fP (1\-\s-1ESPS\s+1)+
and other programs that read RED, GREEN, and BLUE (RGB)
intensity values for controlling the displayed color.
.PP
As a bit of background,
on most color monitors,
the color associated with each pixel on the screen
is made of the combination of three
phosphors: red, blue, and green.
The intensity of all three colors can be modified independently
to produce a spectrum of colors.
If all three colors are fully illuminated (set to 255), the 
resulting color is white; if they are turned off
(set to a value of 0), the resulting color is black.
As the intensity of the red, green, and blue varies,
the three phosphors are mixed to produce a color.
For example,
equal parts red and green at full intensity, but no blue, produce yellow.
.PP
When invoked,
\fIxcmap\fP pops up two windows: a control panel and a
"colormap window".
The control panel has fields for "INPUT file", "OUTPUT file", and
"QUIT!", and a slider control for "Brightness".
The colormap window has a colormap displayed,
a RED\-BLUE\-GREEN color triangle, and numeric display of
colormap index (Level), RED intensity (R), GREEN intensity (G), and
BLUE intensity (B).
When the mouse cursor is in the colormap or slightly below,
the Level and R, G, B displays apply
to the colormap entry closest to the mouse cursor.
When the mouse is in the color triangle with the left button held down,
the displays apply to the entry being modified.
See below for how to modify the colormap.
.PP
By default, the colormap displayed
is a white (left edge) to black (right edge)
colormap. (Each entry in the colormap table contains equal
red, blue, and green intensities, but the
intensities decrease as you move to the right in the displayed
colormap.)
An initial colormap for editing can be loaded by
entering the colormap file name in the "INPUT file" field.
The "Brightness" slider provides a way to multiply all three
phosphor intensities by a common value between 0 an 1.
A brightness value of 1000, multiplies all intensities by 1;
a brightness value of 500, multiplies by .5; and so on.
Once you have a colormap that you want to keep,
simply type its name into the "OUTPUT file" field and hit return on the 
keyboard;
it will be immediately written out.
Clicking the left mouse button on the "Quit!"
field exits the colormap program.
.PP
To modify a colormap, 
the region of interest is selected by
clicking the left mouse button in 
the colormap at three different places. This results in
"handles" being dropped from the colormap.
Three adjacent handles define a region of interest.
When many handles have been dropped
from the map, the region of interest can be identified
by finding the thick handle. The handles to the left and
right of the thick one
delimit the active region. To activate a new region,
click the left mouse button near the middle
handle (but out of the colormap).
Handles can be deleted by using the middle mouse button.
.PP
Color mixing is done by holding the left mouse button
down while moving the mouse cursor in the RGB color triangle.
The color of the selected handle (the thick one)
is directly controlled, and
RGB intensity levels are linearly interpolated
between it and the intensities at the two adjacent handles.
By left mouse clicking in the "Brightness" slider,
the intensity of the selected handle can be directly
changed.
.PP
Several colormaps are in ../esps/lib/waves;
you may want to use one of them as a starting point.
.SH OPTIONS
None.
.SH "ESPS PARAMETERS"
None.
.SH "ESPS COMMON"
Neither read nor written.
.SH "FUTURE CHANGES"
.PP
Probably many, but not under suntools.
.SH "WARNINGS AND DIAGNOSTICS"
.PP
Colormap generation is a bit of an art and \fIxcmap\fP (1\-\s-1ESPS\s+1)
is a bit crude, so patience is required when using it to
make colormaps.
.PP
The colormap size is fixed at 128 entries.
No matter how many entries are specified when
generating a colormap,
linear interpolation is used to generate the rest
of the values.
.SH "BUGS"
.PP
None known.  
.SH "AUTHOR"
.PP
Code by David Talkin.  Manual page by David Burton.
Conversion to XView by Rod Johnson.