.\" RCSid "$Id: vgaimage.1,v 1.2 2003/12/09 15:59:07 greg Exp $"
.TH VGAIMAGE 1 11/15/93 RADIANCE
.SH NAME
vgaimage - RADIANCE picture display program for VGA
.SH SYNOPSIS
.B vgaimage
[
.B "\-c ncolors"
][
.B \-d
][
.B \-b
][
.B \-m
][
.B "\-g gamma"
][
.B "\-e +/-stops"
]
.B pixfile
.SH DESCRIPTION
.I Vgaimage
takes the RADIANCE picture file
.I pixfile
and displays it on a VGA or Super VGA card.
The
.I \-c
option specifies the number of colors to use (default fills color table).
The
.I \-d
option turns off color dithering.
The
.I \-b
option displays the image in black and white (greyscale).
The
.I \-m
option forces monochrome output.
The
.I \-g
option specifies the exponent used in gamma correction;
the default value is given by the environment variable GAMMA, or
2.2 if GAMMA is undefined.
The
.I \-e
option specifies an exposure compensation in f-stops (powers of two).
Only integer stops are allowed, for efficiency.
.PP
If no
.I pixfile
is given, input is read from stdin provided either the
.I \-b
or
.I \-m
option is in effect.
.SH COMMANDS
Once a picture is displayed, the user
may perform a number of operations.
Some of the operations make use of an area of interest, defined by pressing
a mouse button and dragging the cursor over a section of the image.
Pressing a button and immediately releasing it defines a single point as
the area of interest.
A command is a single character.
.TP 10n
.BR q
Quit program.
.TP
.BR <return>
Display the radiance averaged over the area of interest.
.TP
.BR l
Display the luminance value in the area of interest.
.TP
.BR c
Display the color in the area of interest.
.SH ENVIRONMENT
GAMMA		the default gamma correction value
.SH AUTHORS
Greg Ward
.SH "SEE ALSO"
aedimage(1), pfilt(1), rpict(1), rtrace(1), ximage(1)