Module: ColorToGray

Color to Gray converts an image with three color channels to a set of individual grayscale images.

This module converts RGB (Red, Green, Blue) color images to grayscale. All channels can be merged into one grayscale image (Combine), or each channel can be extracted into a separate grayscale image (Split). If you use Combine, the relative weights will adjust the contribution of the colors relative to each other.

Note:All Identify modules require grayscale images.

See also GrayToColor.

Settings:

Conversion method

How do you want to convert the color image?

Image type

Many images contain color channels other than red, green and blue. For instance, GIF and PNG formats can have an alpha channel that encodes transparency. TIF formats can have an arbitrary number of channels which represent pixel measurements made by different detectors, filters or lighting conditions. This setting provides three options to choose from:

Relative weight of the red channel

(Used only when combining channels)
Relative weights: If all relative weights are equal, all three colors contribute equally in the final image. To weight colors relative to each other, increase or decrease the relative weights.

Relative weight of the green channel

(Used only when combining channels)
Relative weights: If all relative weights are equal, all three colors contribute equally in the final image. To weight colors relative to each other, increase or decrease the relative weights.

Relative weight of the blue channel

(Used only when combining channels)
Relative weights: If all relative weights are equal, all three colors contribute equally in the final image. To weight colors relative to each other, increase or decrease the relative weights.

Channel number

This setting chooses a channel to be processed. Red: 1 is the first channel in a .TIF or the red channel in a traditional image file. Green: 2 and Blue: 3 are the second and third channels of a TIF or the green and blue channels in other formats. Alpha: 4 is the transparency channel for image formats that support transparency and is channel # 4 for a .TIF file. ColorToGray will fail to process an image if you select a channel that is not supported by that image, for example, "5" for a .PNG file

Relative weight of the channel

(Used only when combining channels)
Relative weights: If all relative weights are equal, all three colors contribute equally in the final image. To weight colors relative to each other, increase or decrease the relative weights.

Image name

This is the name of the grayscale image that holds the image data from the chosen channel.