Namespace: go.std.image.color

v1.0

Contents

• Summary
• Index
• Constants
• Variables
• Functions, Macros, and Special Forms
• Types

Summary

Provides a low-level interface to the image/color package.

Package color implements a basic color library.

Index

• *Alpha
• *Alpha16
• *CMYK
• *Gray
• *Gray16
• *NRGBA
• *NRGBA64
• *NYCbCrA
• *Palette
• *RGBA
• *RGBA64
• *YCbCr
• Alpha
• Alpha16
• Alpha16Model
• AlphaModel
• Black
• CMYK
• CMYKModel
• CMYKToRGB
• Color
• Gray
• Gray16
• Gray16Model
• GrayModel
• Model
• NRGBA
• NRGBA64
• NRGBA64Model
• NRGBAModel
• NYCbCrA
• NYCbCrAModel
• Opaque
• Palette
• RGBA
• RGBA64
• RGBA64Model
• RGBAModel
• RGBToCMYK
• RGBToYCbCr
• Transparent
• White
• YCbCr
• YCbCrModel
• YCbCrToRGB
• arrayOfAlpha
• arrayOfAlpha16
• arrayOfCMYK
• arrayOfColor
• arrayOfGray
• arrayOfGray16
• arrayOfModel
• arrayOfNRGBA
• arrayOfNRGBA64
• arrayOfNYCbCrA
• arrayOfPalette
• arrayOfRGBA
• arrayOfRGBA64
• arrayOfYCbCr

Legend

Constant Variable Function Macro Special form Type GoVar Receiver/Method

Constants

Constants are variables with :const true in their metadata. Joker currently does not recognize them as special; as such, it allows redefining them or their values.

(None.)

Variables

• Alpha16Model

  Var v1.0

  Models for the standard color types.
  

• AlphaModel

  Var v1.0

  Models for the standard color types.
  

• Black

  Var v1.0

  Standard colors.
  

• CMYKModel

  Var v1.0

  CMYKModel is the Model for CMYK colors.
  

• Gray16Model

  Var v1.0

  Models for the standard color types.
  

• GrayModel

  Var v1.0

  Models for the standard color types.
  

• NRGBA64Model

  Var v1.0

  Models for the standard color types.
  

• NRGBAModel

  Var v1.0

  Models for the standard color types.
  

• NYCbCrAModel

  Var v1.0

  NYCbCrAModel is the Model for non-alpha-premultiplied Y'CbCr-with-alpha
  colors.
  

• Opaque

  Var v1.0

  Standard colors.
  

• RGBA64Model

  Var v1.0

  Models for the standard color types.
  

• RGBAModel

  Var v1.0

  Models for the standard color types.
  

• Transparent

  Var v1.0

  Standard colors.
  

• White

  Var v1.0

  Standard colors.
  

• YCbCrModel

  Var v1.0

  YCbCrModel is the Model for Y'CbCr colors.
  

Functions, Macros, and Special Forms

• CMYKToRGB

  Function v1.0

  (CMYKToRGB c m y k)
  

  CMYKToRGB converts a CMYK quadruple to an RGB triple.
  
  Go input arguments: (c uint8, m uint8, y uint8, k uint8)
  
  Go returns: (uint8, uint8, uint8)
  
  Joker input arguments: [^Int c, ^Int m, ^Int y, ^Int k]
  
  Joker returns: [^Int, ^Int, ^Int]

• RGBToCMYK

  Function v1.0

  (RGBToCMYK r g b)
  

  RGBToCMYK converts an RGB triple to a CMYK quadruple.
  
  Go input arguments: (r uint8, g uint8, b uint8)
  
  Go returns: (uint8, uint8, uint8, uint8)
  
  Joker input arguments: [^Int r, ^Int g, ^Int b]
  
  Joker returns: [^Int, ^Int, ^Int, ^Int]

• RGBToYCbCr

  Function v1.0

  (RGBToYCbCr r g b)
  

  RGBToYCbCr converts an RGB triple to a Y'CbCr triple.
  
  Go input arguments: (r uint8, g uint8, b uint8)
  
  Go returns: (uint8, uint8, uint8)
  
  Joker input arguments: [^Int r, ^Int g, ^Int b]
  
  Joker returns: [^Int, ^Int, ^Int]

• YCbCrToRGB

  Function v1.0

  (YCbCrToRGB y cb cr)
  

  YCbCrToRGB converts a Y'CbCr triple to an RGB triple.
  
  Go input arguments: (y uint8, cb uint8, cr uint8)
  
  Go returns: (uint8, uint8, uint8)
  
  Joker input arguments: [^Int y, ^Int cb, ^Int cr]
  
  Joker returns: [^Int, ^Int, ^Int]

Types

• *Alpha

  Concrete Type v1.0

  Alpha represents an 8-bit alpha color.
  

• *Alpha16

  Concrete Type v1.0

  Alpha16 represents a 16-bit alpha color.
  

• *CMYK

  Concrete Type v1.0

  CMYK represents a fully opaque CMYK color, having 8 bits for each of cyan,
  magenta, yellow and black.
  
  It is not associated with any particular color profile.
  

• *Gray

  Concrete Type v1.0

  Gray represents an 8-bit grayscale color.
  

• *Gray16

  Concrete Type v1.0

  Gray16 represents a 16-bit grayscale color.
  

• *NRGBA

  Concrete Type v1.0

  NRGBA represents a non-alpha-premultiplied 32-bit color.
  

• *NRGBA64

  Concrete Type v1.0

  NRGBA64 represents a non-alpha-premultiplied 64-bit color,
  having 16 bits for each of red, green, blue and alpha.
  

• *NYCbCrA

  Concrete Type v1.0

  NYCbCrA represents a non-alpha-premultiplied Y'CbCr-with-alpha color, having
  8 bits each for one luma, two chroma and one alpha component.
  

• *Palette

  Concrete Type v1.0

  Palette is a palette of colors.
  

• *RGBA

  Concrete Type v1.0

  RGBA represents a traditional 32-bit alpha-premultiplied color, having 8
  bits for each of red, green, blue and alpha.
  
  An alpha-premultiplied color component C has been scaled by alpha (A), so
  has valid values 0 <= C <= A.
  

• *RGBA64

  Concrete Type v1.0

  RGBA64 represents a 64-bit alpha-premultiplied color, having 16 bits for
  each of red, green, blue and alpha.
  
  An alpha-premultiplied color component C has been scaled by alpha (A), so
  has valid values 0 <= C <= A.
  

• *YCbCr

  Concrete Type v1.0

  YCbCr represents a fully opaque 24-bit Y'CbCr color, having 8 bits each for
  one luma and two chroma components.
  
  JPEG, VP8, the MPEG family and other codecs use this color model. Such
  codecs often use the terms YUV and Y'CbCr interchangeably, but strictly
  speaking, the term YUV applies only to analog video signals, and Y' (luma)
  is Y (luminance) after applying gamma correction.
  
  Conversion between RGB and Y'CbCr is lossy and there are multiple, slightly
  different formulae for converting between the two. This package follows
  the JFIF specification at https://www.w3.org/Graphics/JPEG/jfif3.pdf.
  

• Alpha

  Concrete Type v1.0

  Alpha represents an 8-bit alpha color.
  

• RGBA

  Receiver for Alpha v1.0

  ([])
  

• Alpha16

  Concrete Type v1.0

  Alpha16 represents a 16-bit alpha color.
  

• RGBA

  Receiver for Alpha16 v1.0

  ([])
  

• CMYK

  Concrete Type v1.0

  CMYK represents a fully opaque CMYK color, having 8 bits for each of cyan,
  magenta, yellow and black.
  
  It is not associated with any particular color profile.
  

• RGBA

  Receiver for CMYK v1.0

  ([])
  

• Color

  Abstract Type v1.0

  Color can convert itself to alpha-premultiplied 16-bits per channel RGBA.
  The conversion may be lossy.
  

• RGBA

  Method for Color v1.0

  ([])
  

• Gray

  Concrete Type v1.0

  Gray represents an 8-bit grayscale color.
  

• RGBA

  Receiver for Gray v1.0

  ([])
  

• Gray16

  Concrete Type v1.0

  Gray16 represents a 16-bit grayscale color.
  

• RGBA

  Receiver for Gray16 v1.0

  ([])
  

• Model

  Abstract Type v1.0

  Model can convert any Color to one from its own color model. The conversion
  may be lossy.
  

• Convert

  Method for Model v1.0

  ([c])
  

• NRGBA

  Concrete Type v1.0

  NRGBA represents a non-alpha-premultiplied 32-bit color.
  

• RGBA

  Receiver for NRGBA v1.0

  ([])
  

• NRGBA64

  Concrete Type v1.0

  NRGBA64 represents a non-alpha-premultiplied 64-bit color,
  having 16 bits for each of red, green, blue and alpha.
  

• RGBA

  Receiver for NRGBA64 v1.0

  ([])
  

• NYCbCrA

  Concrete Type v1.0

  NYCbCrA represents a non-alpha-premultiplied Y'CbCr-with-alpha color, having
  8 bits each for one luma, two chroma and one alpha component.
  

• RGBA

  Receiver for NYCbCrA v1.0

  ([])
  

• Palette

  Concrete Type v1.0

  Palette is a palette of colors.
  

• Convert

  Receiver for Palette v1.0

  ([c])
  

  Convert returns the palette color closest to c in Euclidean R,G,B space.
  

• Index

  Receiver for Palette v1.0

  ([c])
  

  Index returns the index of the palette color closest to c in Euclidean
  R,G,B,A space.
  

• RGBA

  Concrete Type v1.0

  RGBA represents a traditional 32-bit alpha-premultiplied color, having 8
  bits for each of red, green, blue and alpha.
  
  An alpha-premultiplied color component C has been scaled by alpha (A), so
  has valid values 0 <= C <= A.
  

• RGBA

  Receiver for RGBA v1.0

  ([])
  

• RGBA64

  Concrete Type v1.0

  RGBA64 represents a 64-bit alpha-premultiplied color, having 16 bits for
  each of red, green, blue and alpha.
  
  An alpha-premultiplied color component C has been scaled by alpha (A), so
  has valid values 0 <= C <= A.
  

• RGBA

  Receiver for RGBA64 v1.0

  ([])
  

• YCbCr

  Concrete Type v1.0

  YCbCr represents a fully opaque 24-bit Y'CbCr color, having 8 bits each for
  one luma and two chroma components.
  
  JPEG, VP8, the MPEG family and other codecs use this color model. Such
  codecs often use the terms YUV and Y'CbCr interchangeably, but strictly
  speaking, the term YUV applies only to analog video signals, and Y' (luma)
  is Y (luminance) after applying gamma correction.
  
  Conversion between RGB and Y'CbCr is lossy and there are multiple, slightly
  different formulae for converting between the two. This package follows
  the JFIF specification at https://www.w3.org/Graphics/JPEG/jfif3.pdf.
  

• RGBA

  Receiver for YCbCr v1.0

  ([])
  

• arrayOfAlpha

  Concrete Type v1.0

  Alpha represents an 8-bit alpha color.
  

• arrayOfAlpha16

  Concrete Type v1.0

  Alpha16 represents a 16-bit alpha color.
  

• arrayOfCMYK

  Concrete Type v1.0

  CMYK represents a fully opaque CMYK color, having 8 bits for each of cyan,
  magenta, yellow and black.
  
  It is not associated with any particular color profile.
  

• arrayOfColor

  Concrete Type v1.0

  Color can convert itself to alpha-premultiplied 16-bits per channel RGBA.
  The conversion may be lossy.
  

• arrayOfGray

  Concrete Type v1.0

  Gray represents an 8-bit grayscale color.
  

• arrayOfGray16

  Concrete Type v1.0

  Gray16 represents a 16-bit grayscale color.
  

• arrayOfModel

  Concrete Type v1.0

  Model can convert any Color to one from its own color model. The conversion
  may be lossy.
  

• arrayOfNRGBA

  Concrete Type v1.0

  NRGBA represents a non-alpha-premultiplied 32-bit color.
  

• arrayOfNRGBA64

  Concrete Type v1.0

  NRGBA64 represents a non-alpha-premultiplied 64-bit color,
  having 16 bits for each of red, green, blue and alpha.
  

• arrayOfNYCbCrA

  Concrete Type v1.0

  NYCbCrA represents a non-alpha-premultiplied Y'CbCr-with-alpha color, having
  8 bits each for one luma, two chroma and one alpha component.
  

• arrayOfPalette

  Concrete Type v1.0

  Palette is a palette of colors.
  

• arrayOfRGBA

  Concrete Type v1.0

  RGBA represents a traditional 32-bit alpha-premultiplied color, having 8
  bits for each of red, green, blue and alpha.
  
  An alpha-premultiplied color component C has been scaled by alpha (A), so
  has valid values 0 <= C <= A.
  

• arrayOfRGBA64

  Concrete Type v1.0

  RGBA64 represents a 64-bit alpha-premultiplied color, having 16 bits for
  each of red, green, blue and alpha.
  
  An alpha-premultiplied color component C has been scaled by alpha (A), so
  has valid values 0 <= C <= A.
  

• arrayOfYCbCr

  Concrete Type v1.0

  YCbCr represents a fully opaque 24-bit Y'CbCr color, having 8 bits each for
  one luma and two chroma components.
  
  JPEG, VP8, the MPEG family and other codecs use this color model. Such
  codecs often use the terms YUV and Y'CbCr interchangeably, but strictly
  speaking, the term YUV applies only to analog video signals, and Y' (luma)
  is Y (luminance) after applying gamma correction.
  
  Conversion between RGB and Y'CbCr is lossy and there are multiple, slightly
  different formulae for converting between the two. This package follows
  the JFIF specification at https://www.w3.org/Graphics/JPEG/jfif3.pdf.