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Color to GrayScale

Group (Subgroup)

Processing (Image)


This Filter allows the user to select a flattening method for turning an array of RGB or RGBa values into grayscale values.

  • Luminosity: The luminosity method is a more sophisticated version of the average method. It also averages the values, but it forms a weighted average to account for human perception. We re more sensitive to green than other colors, so green is weighted most heavily. The default formula for luminosity is BT709 Greyscale: Red: 0.2125 Green: 0.7154 Blue: 0.0721. The user can set the weightings to what ever values they would like.
  • Average (R + G + B) / 3
  • Lightness (max(R, G, B) + min(R, G, B)) / 2
  • Color Channel: The user selects a specific R|G|B channel to use as the GrayScale values.

The user can select 1 or more image data arrays which are assumed to be multi-component arrays of unsigned 8 bit values. The user can create a new AttributeMatrix if they want to store all the newly created arrays in a separate AttributeMatrix.

Additional GrayScale Conversions

The following are some additional accepted grayscale conversions

  • RMY Greyscale: Red: 0.5 Green: 0.419 Blue: 0.081
  • (YIQ/NTSC): Red: 0.299 Green: 0.587 Blue: 0.114


Name Type Description
Flattening Method Enumeration Which method to use when flattening the RGB array
Luminosity Triplet 3xFloats Only used if Luminosity is selected as conversion method
Color Channel 1 Int Only needed if the Color Channel conversion method is selected
Output Array Prefix String This prefix will be added to each array name that is selected for conversion to form the new array name

Required Geometry

Not Applicable

Required Objects

Kind Default Name Type Component Dimensions Description
Element Attribute Array(s) ImageData uint8_t (3) or (4) RGB or RGBA values

Created Objects

Kind Default Name Type Component Dimensions (dimension, size) Description
Element Attribute Array GrayScale Data uint8_t (1) Grayscale values
AttributeMatrix (Optional)

Example Pipelines

Please see the description file distributed with this Plugin

DREAM.3D Mailing Lists

If you need more help with a Filter, please consider asking your question on the DREAM.3D Users Google group!