LinearGradientImage

LinearGradientImage[gcol]

returns an image with values linearly changing from left to right based on gradient color gcol.

LinearGradientImage[{pos1,pos2}gcol]

returns an image where the gradient starts at pos1 and ends at pos2.

LinearGradientImage[…,size]

returns a linear gradient image of the specified size.

LinearGradientImage[…,size,"type"]

gives an image converted to the specified type.

Details and Options

  • LinearGradientImage constructs a 2D or 3D image with constant gradient along a direction derived from the input specification.
  • Color scheme specification gcol can be any of the following:
  • {col1,col2,…}blend of multiple color directives coli
    "name"ColorData["name"]
    ffunction f that returns a color based on a scalar distance
  • The argument passed to the function f is by default the normalized distance between a pixel and the line going through pos1, perpendicular to pos2-pos1.
  • Position specification posi can be any of the following:
  • {x,y} or {x,y,z}absolute pixel position
    Left,Right axis in 2D and 3D
    Bottom,Top axis in 2D, axis in 3D
    Front,Back axis in 3D
    Centercenter alignment
    {posx,…}a list of named positions
  • Positions that are not constrained are taken to be centered.
  • By default, positions are assumed to be in the standard image coordinate system.
  • The size specification can be one of the following:
  • side2D image of size {side,side}
    {width,height}2D image size specification
    {width,depth,height}3D image size specification
  • The default size is {150,150} for 2D images and {64,64,64} for 3D images.
  • LinearGradientImage[] is equivalent to LinearGradientImage[{Black,White}].
  • LinearGradientImage accepts all Image and Image3D options with the following additions and changes:
  • ColorFunction Automatichow each pixel should be colored
    ColorFunctionScaling Truewhether to scale the argument to ColorFunction
    DataRange Fullrange of coordinates in the original image
    Padding "Fixed"padding scheme
  • Possible settings for DataRange include:
  • Automatic{{0,1},{0,h/w}} in 2D, {{0,1},{0,d/w},{0,h/w}} in 3D
    Full{{0,w},{0,h}} in 2D, {{0,w},{0,d},{0,h}} in 3D (default)
    {{left,right},{bottom,top}}explicit coordinate ranges in 2D
    {{left,right},{front,back},{bottom,top}}explicit coordinate ranges in 3D

Examples

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Basic Examples  (4)

Linear grayscale gradient from left to right:

Linear blend of colors from left to right:

Linear gradient image along a given direction:

Specify the output size:

Scope  (14)

Color Schemes  (5)

Linear blend of two colors:

Linear blend of multiple colors:

Use a gradient color scheme:

Use hue as the coloring function:

Specify a custom color function:

Positions  (6)

By default, a linear gradient image from left to right is generated:

A top-to-bottom gradient image:

A diagonal gradient image:

If position along one dimension is not given, center alignment is used for that dimension:

Left-to-right 3D gradient image:

Diagonal 3D gradient image:

Size  (3)

By default, a 2D image of size is generated:

If absolute pixel positions are given, the minimum image dimensions containing the positions are returned:

Specify a different output size:

By default, a 3D image of size is generated:

Specify the output size:

Options  (8)

ColorFunction  (3)

With no color specification, GrayLevel is the default color function:

Specify a different color function:

Use a built-in color gradient:

Use Blend to specify a color function that is a blend of multiple colors:

When grayscale 3D images are produced, ColorFunction->"GrayLevelOpacity" is used in Image3D:

With both ColorFunction and end point colors specified, color function is ignored:

ColorFunctionScaling  (2)

By default, the color function parameters are rescaled between 0 and 1:

Scaled values might not be suitable for some color functions:

Use ColorFunctionScaling->False:

DataRange  (2)

The default DataRange is the size of the image:

Specify a different data range:

Use a normalized data range to get the same effect, regardless of the image dimensions:

Padding  (1)

By default, "Fixed" padding is used:

Use a constant padding value:

Specify a padding scheme:

Applications  (2)

Apply Bayer's 4×4 dispersed-dot dither matrix to a gradient image:

Apply different gradient effects to an image:

Wolfram Research (2014), LinearGradientImage, Wolfram Language function, https://reference.wolfram.com/language/ref/LinearGradientImage.html (updated 2020).

Text

Wolfram Research (2014), LinearGradientImage, Wolfram Language function, https://reference.wolfram.com/language/ref/LinearGradientImage.html (updated 2020).

CMS

Wolfram Language. 2014. "LinearGradientImage." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2020. https://reference.wolfram.com/language/ref/LinearGradientImage.html.

APA

Wolfram Language. (2014). LinearGradientImage. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/LinearGradientImage.html

BibTeX

@misc{reference.wolfram_2024_lineargradientimage, author="Wolfram Research", title="{LinearGradientImage}", year="2020", howpublished="\url{https://reference.wolfram.com/language/ref/LinearGradientImage.html}", note=[Accessed: 22-November-2024 ]}

BibLaTeX

@online{reference.wolfram_2024_lineargradientimage, organization={Wolfram Research}, title={LinearGradientImage}, year={2020}, url={https://reference.wolfram.com/language/ref/LinearGradientImage.html}, note=[Accessed: 22-November-2024 ]}