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ColorDistanceImage


Module: FoundationPro

Compares each pixel with the specified color using chromatic and non-chromatic information.

Applications

Color analysis insensitive to changes of illumination.
Name Type Range Description
Input value inImage Image Unsigned color image used in comparison
Input value inRoi Region* Range of pixels to be processed
Input value inRgbColor Pixel Color to compare the image to
Input value inChromaAmount Real 0.0 - 1.0 Proportion of chromatic information in distance computation
Output value outValueImage Image Unsigned image of distances

Requirements

For input inImage only pixel formats are supported: 1⨯uint8, 2⨯uint8, 3⨯uint8, 4⨯uint8.

Read more about pixel formats in Image documentation.

Description

The operation computes the distance between each pixel of inImage and a specified color, presenting result as a monochromatic image. Input image should be in RGB color space.

The distance between pixels is computed using two measures:

  • Value distance - the difference between average channel values
  • Chromatic distance - euclidean distance between pixels normalized to the same value level

The resulting distance is computed as a weighted average of these two values, parameter inChromaAmount ( 0.0 - 1.0 ) being the weight of the chromatic distance, and 1 - inChromaAmount being the weight of the value distance.

Examples

ColorDistanceImage run with inRgbColor = , inChromaAmount = 0.8

Hardware Acceleration

This operation supports automatic parallelization for multicore and multiprocessor systems.

Errors

This filter can throw an exception to report error. Read how to deal with errors in Error Handling.

List of possible exceptions:

Error type Description
DomainError Invalid image Depth in ColorDistanceImage.
DomainError Not supported inImage pixel format in ColorDistanceImage. Supported formats: 1xUInt8, 2xUInt8, 3xUInt8, 4xUInt8.
RuntimeError Each pixel component of inRgbColor must be nonnegative in ColorDistanceImage.

Complexity Level

This filter is available on Advanced Complexity Level.

See Also

  • ColorDistance – Compares two pixels using chromatic and non-chromatic information. Assumes RGB color space.
  • ThresholdImage_Color – Transforms each pixel value to maximum or minimum depending on the distance from a given color.