This is documentation for Mathematica 8, which was
based on an earlier version of the Wolfram Language.

# Raster

 Rasteris a two-dimensional graphics primitive which represents a rectangular array of gray cells. Rasterrepresents an array of RGB color cells. Rasterrepresents an array of color cells with opacity . Rasterrepresents an array of gray cells with the specified opacities.
• Raster[array, ColorFunction->f] specifies that each cell should be colored using the graphics directives obtained by applying the function f to the value specified for that cell.
• Scaled and Offset can be used to specify the coordinates for the rectangle.
• Raster specifies that cell values should be scaled so that corresponds to 0 and corresponds to 1. Cell values outside this range are clipped to be 0 or 1.
Rectangular array of gray cells:
Array of RGB color cells:
Array of gray cells with opacity:
Array of RGB cells with opacity:
Rectangular array of gray cells:
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Array of RGB color cells:
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Array of gray cells with opacity:
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Array of RGB cells with opacity:
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 Scope   (14)
For an × matrix, the raster occupies the rectangle to :
Specify the shape of the raster explicitly, using ordinary coordinates:
Use Offset:
A raster of a scalar matrix uses gray level by default:
The values outside the range 0 to 1 are normally clipped to be 0 or 1:
Specify the range of values:
The values outside the specified range are clipped:
An array of pairs of numbers is treated as a gray level with opacity:
A raster of an array of triples uses RGB colors by default:
An array of four numbers is treated as having RGB values with opacity:
Use Hue values for a scalar matrix:
Use a user-defined function:
Use a color function with the specified range:
Any Mathematica expression can be applied to a color function:
 Options   (4)
Use gray level for each cell:
Color the raster cells using hue values:
Use a user-defined color function:
Use a predefined gradient:
 Applications   (3)
Use a raster as wallpaper:
Get a test RGB raster using ExampleData:
Convert RGB to grayscale:
Apply a filter using ListCorrelate, then display it:
Define a simple raster density plot function:
Set options for the function:
Results:
Rotate can be applied to a raster:
Use ArrayPlot when visualizing discrete data:
Use ListDensityPlot when visualizing continuous data:
Use ReliefPlot to visualize elevation data:
Rasterize can generate a raster graphic from any expression:
ExampleData contains a number of test images:
Many Import formats can produce Raster:
The first row in the data array is at the bottom of Raster, but at the top of ArrayPlot:
Different planes through the RGB color space:
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