GAMMA DISPLAY Package (DISP): Reference Manual

rasmph_pwr24

NAME
rasmph_pwr24 - generate 24-bit SUN/BMP raster file of interferogram phase + intensity image

SYNOPSIS
rasmph_pwr24 <cpx> <pwr> <width> [start_cpx] [start_pwr] [nlines] [pixavr] [pixavaz] [scale] [exp] [LR] [rasf] [cc] [start_cc] [cc_min]

<cpx>	(input) complex image (fcomplex, e.g. interferogram)
<pwr>	(input) intensity image (float)
<width>	number of samples/row of cpx and pwr
[start_cpx]	starting line of cpx (default=1)
[start_pwr]	starting line of pwr (default=1)
[nlines]	number of lines to display (default=0: to end of file)
[pixavr]	number of pixels to average in range (default=1)
[pixavaz]	number of pixels to average in azimuth (default=1)
[scale]	pwr display scale factor (default=1.)
[exp]	pwr display exponent (default=.35)
[LR]	left/right flipping flag, (default=1: normal, -1: mirror image)
[rasf]	(output) 24-bit rasterfile (enter - for default=.ras: SUN raster format, .bmp: BMP format)
[cc]	display threshold data file (float, e.g. correlation)
[start_cc]	starting line of cc data file (default=1)
[cc_min]	pixels with cc values below cc_min are displayed using greyscale (default=.2)

EXAMPLE

rasmph_pwr24 19960422_19960421.diff 19969421.rmli 1000 1 1 0 1 1 0.8 .35 1 19960422_19960421.diff.ras

Generates an 24-bit SUN raster file of the complex valued differential interferogram using the backscatter intensity image for the image brightness.

DESCRIPTION
rasmph_pwr24 supports the generation of a 24-bit SUN/BMP raster file image of the phase of a complex valued interferogram displayed in color and the image brightness corresponding to a backscatter intensity image.

In the frame of an IPTA investigation the use of a 24-bit SUN/BMP raster file may be an advantage due to the higher visibility of fine details in the phase and intensity information.

For areas of low coherence (below the indicated threshold), the color is suppressed and the corresponding intensity is displayed in grey. This avoids the high "color noise" of low coherence areas.

Optionally, a sub-section of the entire image, multi-looking in range and azimuth direction, or a left/right flipping can be performed based on the command line options.

Note that all pixels with non-zero data value have non-zero RGB values in the output image so that "no data" is represented by RGB=0,0,0. If the image is converted to PNG or other format that supports transparency, 0,0,0 pixels can then be marked transparent. Using the Imagemagick convert utility:

convert -transparent=black 19960421_19960422.diff.ras 19960421_1996-422.diff.png

will generate a PNG format image with regions with no data marked