ANSI-C program: ras_to_rgb.c
NAME
ras_to_rgb - Combines 3 SUN or BMPraster images into a single
red/green/blue (RGB) 24-bit composite raster image.
SYNOPSIS
ras_to_rgb <red_channel> <green_channel>
<blue_channel> <output> [LR]
[null_flag]
| <red_channel> | input 8-bit SUN or BMP format raster image to be used
for the red channel |
| <green_channel> | input 8-bit SUN or BMP format raster image to be used
for the green channel |
| <blue_channel> | input 8-bit SUN or BMP format raster image to be for
the blue channel |
| <output> | output 24-bit SUN or BMP format RGB raster image |
| [LR] |
image mirror flag: 1: normal (default) -1: mirror image |
| [null_flag] | zero value flag: 0: same as other data (default) 1: if one channel is 0, set to (0,0,0) |
EXAMPLE
ras_to_rgb 19990421_19990422.cc_ad.ras
19990421.mli_frost.ras 19990421_19990422.change.ras
19990421_19990422.rgb.ras 1 0
Combines the adaptively estimated coherence, the Frost filtered backscatter intensity, and the backscatter change into a 24-bit RGB composite raster image.
DESCRIPTION
ras_to_rgb supports merging 3 seperate 8-bit images into
a single 24-bit red/green/blue (RGB) composite image in SUN
raster or BMP format. This program accepts input images coding a
single parameter in a grey scale. Images containing the merged
coherence (as color) and intensity (as brightness), or phase (as
color) and the intensity (as brightness) are not useful as
inputs. Images appropriate as input for ras_to_rgb may
be generated using the programs such as ras_linear and
ras_dB.
The display of multiple channels is very important for the
interpretation of the results. A texture image or a soil moisture
map, for example, show little land features making the
orientation in such an image very difficult. In combination with
a backscatter or coherence image this problem is solved and the
phase or soil moisture information may be associated to surface
features. Sometimes it is an advantage to set the values of all
input channels to NULL if the value of one channel is NULL. As an
example multi-temporal images are may be mentionned. Missing data
on a part of one input image may result in a confusing result if
the values for those areas with the missing data are not set too
NULL. The setting to NULL can be selected by setting the
null_flag to 1.
SEE ALSO
ras_to_hsi, display.h, rasterfile.h, bmp_image.h.