do rdcs

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Contents: Description, Arguments, Usage, Examples, Images, Sub-Functions, Related Functions, Source

Supported Under Version: >1.00

Current .dvrc Version: 1.03

Description

A quick shortcut to make rdcs images with any three bands

Arguments and Return Values

Arguments: A numeric array greater than 3 bands deep, and three band numbers to use in dcs operation

Return Value: A three band bip byte dcs-ed image.

Usage

Syntax: do_dcs(data, band1, band2, band3 [, ignore = VAL] [, sample = VAL] [, variance = VAL] [, xsize = VAL] [, ysize = VAL])

'data' - a multiband numeric array of greater than three bands

'band1 - band3' - the red, green and blue bands in the dcs calculation

'ignore' an optional null value of the data, default = -32768

'sample' an optional color sample array

'variance' an optional color variance specification, default = 50

'ysize' - Any integer for beaking up the data in the y direction. Default of 1000.

'xsize' - Any integer for beaking up the data in the x direction. Default of 4000.

If no bands are specified an 8-7-5 stretch will be attempted.

Examples

dv> a
300x750x10 array of float, bsq format [9,000,000 bytes]

dv> b
300x750x10 array of float, bsq format [9,000,000 bytes]

dv> display(do_rdcs(a,9,6,4))

dv> display(do_rdcs(a,7,5,3,ignore = -32768))

dv> pic = do_rdcs(a,variance = cat(80,50,50,axis = y))
300x750x3 array of byte, bip format [675,000 bytes]

dv> pic = do_rdcs(a,ignore = 0,sample = b)
300x750x3 array of byte, bip format [675,000 bytes]

Images

The stretch of the left image is dominated by the canyon's huge difference in values (visible as orange in the bottom of the canyon) and consequently the plains appear washed out by the purple/blue color. The stretch on the right is more consistent throughout normalizing the plains above the canyon to have a similar stretch as the canyon itself.