d.rgb(1) - f14

1d.rgb(1)                      Grass User's Manual                     d.rgb(1)
2
3
4

NAME

6       d.rgb  - Displays three user-specified raster map layers as red, green,
7       and blue overlays in the active graphics frame.
8

KEYWORDS

10       display
11

SYNOPSIS

13       d.rgb
14       d.rgb help
15       d.rgb [-ox] red=name green=name blue=name  [--verbose]  [--quiet]
16
17   Flags:
18       -o
19           Overlay (non-null values only)
20
21       -x
22           Don't add to list of commands in monitor
23
24       --verbose
25           Verbose module output
26
27       --quiet
28           Quiet module output
29
30   Parameters:
31       red=name
32           Name of raster map to be used for
33
34       green=name
35           Name of raster map to be used for
36
37       blue=name
38           Name of raster map to be used for
39

DESCRIPTION

41       RGB stands for red, green, and blue.  This  program  visually  combines
42       three raster map layers to form a color image. For each layer, the cor‐
43       responding component from the layer's color table is used (e.g. for the
44       red  layer, the red component is used, and so on). In general, the lay‐
45       ers should use a grey-scale color table.
46

OPTIONS

48   Flags:
49       -o
50              Overlay the resulting raster map layer onto whatever is  already
51              displayed in the active graphics frame. Any no-data areas in any
52              of the named raster maps will seem transparent, and  reveal  the
53              underlying  image previously displayed in the graphics frame. If
54              the -o flag is set, only cells containing non-null  values  will
55              be  displayed  from  the  overlaid  raster  map. All other areas
56              (i.e., the portions of the overlaid map that contain  null  val‐
57              ues) will leave the underlying display untouched.
58
59   Parameters:
60       red=name
61              Name of raster map layer to be used for RED component.
62
63       green=name
64              Name of raster map layer to be used for GREEN component.
65
66       blue=name
67              Name of raster map layer to be used for BLUE component.
68

NOTES

70       This  is  a  new version of d.rgb, which sends the data to the graphics
71       monitor in true-color RGB format.  Unlike the previous version, it does
72       not  attempt to quantize the combined image into a fixed number of col‐
73       ors.  Nor does it have an option to generate a  composite  layer.   The
74       image  and  raster map layers will not display properly if the graphics
75       device does not have a reasonable sampling of the RGB color-space.
76
77       If color quality of satellite image color composites  seems  to  appear
78       poor, run r.colors on the selected satellite channels.
79
80       Example:
81       r.info -r image.1
82       min=0
83       max=255
84       r.colors map=image.1 color=rules << EOF
85       0 black
86       255 white
87       EOF
88       r.colors map=image.2 rast=image.1
89       r.colors map=image.3 rast=image.1
90
91       Note: Future GRASS versions may do this for you automatically.
92       To  write out the color composite to a R/G/B raster maps, use r.compos‐
93       ite.
94

AUTHOR

105       Glynn Clements
106
107       Last changed: $Date: 2005-03-01 21:15:12 +0100 (Tue, 01 Mar 2005) $
108
109       Full index
110
111       © 2003-2008 GRASS Development Team
112
113
114
115GRASS 6.3.0                                                           d.rgb(1)