1 |
.\" RCSid "$Id: falsecolor.1,v 1.4 2006/11/13 02:41:45 greg Exp $" |
2 |
.TH FALSECOLOR 1 11/15/93 RADIANCE |
3 |
.SH NAME |
4 |
falsecolor - make a false color RADIANCE picture |
5 |
.SH SYNOPSIS |
6 |
.B falsecolor |
7 |
[ |
8 |
.B "\-i input" |
9 |
][ |
10 |
.B "\-p picture" |
11 |
][ |
12 |
.B "\-cb | \-cl" |
13 |
][ |
14 |
.B \-e |
15 |
][ |
16 |
.B "\-s scale" |
17 |
][ |
18 |
.B "\-l label" |
19 |
][ |
20 |
.B "\-n ndivs" |
21 |
][ |
22 |
.B "\-lw lwidth" |
23 |
][ |
24 |
.B "\-lh lheight" |
25 |
][ |
26 |
.B "\-log decades" |
27 |
][ |
28 |
.B "\-m mult" |
29 |
][ |
30 |
.B "\-spec" |
31 |
][ |
32 |
.B "\-r redv" |
33 |
][ |
34 |
.B "\-g grnv" |
35 |
][ |
36 |
.B "\-b bluv" |
37 |
] |
38 |
.SH DESCRIPTION |
39 |
.I Falsecolor |
40 |
produces a false color picture for lighting analysis. |
41 |
Input is a rendered Radiance picture. |
42 |
.PP |
43 |
By default, luminance is displayed on a linear scale from 0 to 1000 nits, where |
44 |
dark areas are blue and brighter areas move through the spectrum to red. |
45 |
A different scale can be given with the |
46 |
.I \-s |
47 |
option. |
48 |
If the argument given to |
49 |
.I \-s |
50 |
begins with an "a" for "auto," then the maximum is used for scaling the result. |
51 |
The default multiplier is 179, which converts from radiance or irradiance |
52 |
to luminance or illuminance, respectively. |
53 |
A different multiplier can be given with |
54 |
.I \-m |
55 |
to get daylight factors or whatever. |
56 |
For a logarithmic rather than a linear mapping, the |
57 |
.I \-log |
58 |
option can be used, where |
59 |
.I decades |
60 |
is the number of decades below the maximum scale desired. |
61 |
.PP |
62 |
A legend is produced for the new image with a label given by the |
63 |
.I \-l |
64 |
option. |
65 |
The default label is "Nits", which is appropriate for standard Radiance |
66 |
images. |
67 |
If the |
68 |
.I -i |
69 |
option of |
70 |
.I rpict(1) |
71 |
was used to produce the image, then the appropriate label would be "Lux". |
72 |
.PP |
73 |
If contour lines are desired rather than just false color, the |
74 |
.I \-cl |
75 |
option can be used. |
76 |
These lines can be placed over another Radiance picture using the |
77 |
.I -p |
78 |
option. |
79 |
If the input picture is given with |
80 |
.I \-ip |
81 |
instead of |
82 |
.I \-i, |
83 |
then it will be used both as the source of values and as the picture |
84 |
to overlay with contours. |
85 |
The |
86 |
.I \-cb |
87 |
option produces contour bands instead of lines, where the thickness of |
88 |
the bands is related to the rate of change in the image. |
89 |
The |
90 |
.I \-n |
91 |
option can be used to change the number of contours (and corresponding |
92 |
legend entries) from the default value of 8. |
93 |
The |
94 |
.I \-lw |
95 |
and |
96 |
.I \-lh |
97 |
options may be used to change the legend dimensions from the default width |
98 |
and height of 100x200. |
99 |
A value of zero in either eliminates the legend in the output. |
100 |
.PP |
101 |
The |
102 |
.I \-e |
103 |
option causes extrema points to be printed on the brightest and |
104 |
darkest pixels of the input picture. |
105 |
.PP |
106 |
The |
107 |
.I "\-spec" |
108 |
option reinstates the old, spectral color scale used in the original |
109 |
.I falsecolor. |
110 |
The remaining options, |
111 |
.I "\-r, \-g," |
112 |
and |
113 |
.I \-b |
114 |
are for changing the mapping of values to colors. |
115 |
These are expressions of the variable |
116 |
.I v, |
117 |
where |
118 |
.I v |
119 |
varies from 0 to 1. |
120 |
These options are not recommended for the casual user. |
121 |
.PP |
122 |
If no |
123 |
.I \-i |
124 |
or |
125 |
.I \-ip |
126 |
option is used, input is taken from the standard input. |
127 |
The output image is always written to standard output, which should |
128 |
be redirected. |
129 |
.SH EXAMPLES |
130 |
To create a false color image directly from |
131 |
.I rpict(1): |
132 |
.IP "" .2i |
133 |
rpict \-vf default.vp scene.oct | falsecolor > scene.pic |
134 |
.PP |
135 |
To create a logarithmic contour plot of illuminance values on a |
136 |
Radiance image: |
137 |
.IP "" .2i |
138 |
rpict \-i \-vf default.vp scene.oct > irrad.pic |
139 |
.br |
140 |
rpict \-vf default.vp scene.oct > rad.pic |
141 |
.br |
142 |
falsecolor \-i irrad.pic \-p rad.pic \-cl \-log 2 \-l Lux > lux.pic |
143 |
.SH AUTHOR |
144 |
Greg Ward |
145 |
.SH ACKNOWLEDGEMENT |
146 |
Work on this program was initiated and sponsored by the LESO |
147 |
group at EPFL in Switzerland. |
148 |
.SH "SEE ALSO" |
149 |
getinfo(1), pcomb(1), pcompos(1), pextrem(1), pfilt(1), pflip(1), protate(1), |
150 |
psign(1), rpict(1), ximage(1) |