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ISIS Documentation

hsv2rgb

Convert HSV to RGB

This program takes in three input images, representing Hue, Saturation, and Value, then outputs Red, Green, and Blue files respectively. It works by creating an HSV pixel from pixels in the Hue, Saturation, and Value files, converting it to RGB format, then writing the data to the Red, Green, and Blue files.

HSV Stores colors in terms of hue, saturation, and value. The hue determines the color, which is an angle around the color wheel. The basic colors are: 0 degrees = RED, 60 degrees = YELLOW, 120 degrees = GREEN, 180 degrees = CYAN, 240 degrees = BLUE and 300 degrees = PURPLE. The saturation is how much grey is in the color (intensity of the color). A saturation value of zero means it's perfect, while a saturation value of 1 would cause any color to become pure grey. As an example, the color RGB(255,0,0) is pure so the saturation would be zero. The value is how bright the color is. A value of 0 is always black, and 100 is the color (if not saturated).
In brief,
HUE = COLOR (degrees around the color wheel)
SATURATION = INTENSITY (0-1, 0 being no color/grey)
VALUE = BRIGHTNESS (0 being black)

For more information, see
http://en.wikipedia.org/wiki/Color_spaces

Categories

Related Objects and Documents

Applications

History

Sean Crosby2006-01-05 Original version
Steven Lambright2007-06-20 Added comment explaining what HSV is and what the code is doing. Also, added code for boundary cases.

Parameters

Input Files

This file will be converted from Hue to Red
Type cube
File Mode input
Filter *.cub

This file will be converted from Saturation to Green
Type cube
File Mode input
Filter *.cub

This file will be converted from Value to Blue
Type cube
File Mode input
Filter *.cub

Output Files

The resultant Hue cube
Type cube
File Mode output
Pixel Type real
Filter *.cub

The resultant Saturation cube
Type cube
File Mode output
Pixel Type real
Filter *.cub

The resultant Value cube
Type cube
File Mode output
Pixel Type real
Filter *.cub

Multiplier

This value can be used to alter the DNs of the VALUE image
Type double
Default 1.0
Minimum 0.0 (inclusive)

Example 1

Convert RGB image to HSV

This example shows the results of converting RGB images to HSV format.

Command Line

Convert Hue, Saturation, and Value into their respective Red, Green, and Blue images.
hsv2rgb red=../peaks.cub+5 green=../peaks.cub+4 blue=../peaks.cub+3 hue=../hue.cub saturation=../sat.cub value=../val.cub

GUI Screenshot

HSV2RGB Gui

Example Gui

HSV2RGB Gui

Screenshot of GUI with parameters filled in to perform a conversion from HSV to RGB.

Input Images

Hue image

Input image for hsv2rgb

Hue image

Parameter Name: HUE

This is the input image for the hsv2rgb example.

Saturation image

Input image for hsv2rgb

Saturation image

Parameter Name: SATURATION

This is the input image for the hsv2rgb example.

Value image

Input image for hsv2rgb

Value image

Parameter Name: VALUE

This is the input image for the hsv2rgb example.

Output Images

Output image showing results of hsv2rgb.

Output image

Output image showing results of hsv2rgb.

Parameter Name: RED

This is the output image that results from converting Hue to Red.

Output image showing results of hsv2rgb.

Output image

Output image showing results of hsv2rgb.

Parameter Name: GREEN

This is the output image that results from converting Saturation to Green.

Output image showing results of hsv2rgb.

Output image

Output image showing results of hsv2rgb.

Parameter Name: BLUE

This is the output image that results from converting Value to Blue.