lab2uint8

Convert L*a*b color values to uint8

Description

example

lab8 = lab2uint8(lab) converts L*a*b* color values to type uint8.

Examples

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This example shows how to convert L*a*b* color values from double to uint8.

Create a double vector specifying the color white in L*a*b* colorspace.

w = [100 0 0];

Convert the L*a*b* color value to uint8.

lab2uint8(w)
ans = 1x3 uint8 row vector

   255   128   128

Input Arguments

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Color values to convert, specified as a m-by-3 matrix of color values (one color per row), or an m-by-n-by-3 image array. The input lab matrix must be real and nonsparse.

Data Types: double | uint16

Output Arguments

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Converted color values, returned as a numeric array of same size as the input.

Data Types: uint8

Algorithms

The function converts the L*a*b* color values to type uint8. The Image Processing Toolbox™ software follows the convention that double-precision L*a*b* arrays contain 1976 CIE L*a*b* values. The L*a*b* arrays that are uint8 or uint16 follow the convention in the ICC profile specification (ICC.1:2001-4, www.color.org) for representing L*a*b* values as unsigned 8-bit or 16-bit integers. The ICC encoding convention is illustrated by these tables.

Value (L*)

uint8 Value

uint16 Value

0.0

0

0

100.0

255

65280

100.0 + (25500/65280)

None

65535

Value (a* or b*)

uint8 Value

uint16 Value

-128.0

0

0

0.0

128

32768

127.0

255

65280

127.0 + (255/256)

None

65535

Introduced before R2006a