color

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原文：https://pkg.go.dev/image/color@go1.23.0

Package color implements a basic color library.

​ color 包实现了一个基本的颜色库。

常量

This section is empty.

变量

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var (
	Black       = Gray16{0}
	White       = Gray16{0xffff}
	Transparent = Alpha16{0}
	Opaque      = Alpha16{0xffff}
)

Standard colors.

​ 标准颜色。

函数

func CMYKToRGB <- go1.5

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func CMYKToRGB(c, m, y, k uint8) (uint8, uint8, uint8)

CMYKToRGB converts a CMYK quadruple to an RGB triple.

​ CMYKToRGB 将 CMYK 四元组转换为 RGB 三元组。

func RGBToCMYK <- go1.5

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func RGBToCMYK(r, g, b uint8) (uint8, uint8, uint8, uint8)

RGBToCMYK converts an RGB triple to a CMYK quadruple.

​ RGBToCMYK 将 RGB 三元组转换为 CMYK 四元组。

func RGBToYCbCr

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func RGBToYCbCr(r, g, b uint8) (uint8, uint8, uint8)

RGBToYCbCr converts an RGB triple to a Y’CbCr triple.

​ RGBToYCbCr 将 RGB 三元组转换为 Y’CbCr 三元组。

func YCbCrToRGB

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func YCbCrToRGB(y, cb, cr uint8) (uint8, uint8, uint8)

YCbCrToRGB converts a Y’CbCr triple to an RGB triple.

​ YCbCrToRGB 将 Y’CbCr 三元组转换为 RGB 三元组。

类型

type Alpha

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type Alpha struct {
	A uint8
}

Alpha represents an 8-bit alpha color.

​ Alpha 表示 8 位 alpha 颜色。

(Alpha) RGBA

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func (c Alpha) RGBA() (r, g, b, a uint32)

type Alpha16

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type Alpha16 struct {
	A uint16
}

Alpha16 represents a 16-bit alpha color.

​ Alpha16 表示 16 位 alpha 颜色。

(Alpha16) RGBA

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func (c Alpha16) RGBA() (r, g, b, a uint32)

type CMYK <- go1.5

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type CMYK struct {
	C, M, Y, K uint8
}

CMYK represents a fully opaque CMYK color, having 8 bits for each of cyan, magenta, yellow and black.

​ CMYK 表示完全不透明的 CMYK 颜色，青色、品红色、黄色和黑色各占 8 位。

It is not associated with any particular color profile.

​ 它与任何特定颜色配置文件均无关联。

(CMYK) RGBA <- go1.5

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func (c CMYK) RGBA() (uint32, uint32, uint32, uint32)

type Color

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type Color interface {
	// RGBA returns the alpha-premultiplied red, green, blue and alpha values
	// for the color. Each value ranges within [0, 0xffff], but is represented
	// by a uint32 so that multiplying by a blend factor up to 0xffff will not
	// overflow.
	//
	// An alpha-premultiplied color component c has been scaled by alpha (a),
	// so has valid values 0 <= c <= a.
	RGBA() (r, g, b, a uint32)
}

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

​ Color 可以将自身转换为按通道 RGBA 预乘的 16 位。转换可能会造成损失。

type Gray

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type Gray struct {
	Y uint8
}

Gray represents an 8-bit grayscale color.

​ Gray 表示 8 位灰度颜色。

(Gray) RGBA

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func (c Gray) RGBA() (r, g, b, a uint32)

type Gray16

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type Gray16 struct {
	Y uint16
}

Gray16 represents a 16-bit grayscale color.

​ Gray16 表示 16 位灰度颜色。

(Gray16) RGBA

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func (c Gray16) RGBA() (r, g, b, a uint32)

type Model

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type Model interface {
	Convert(c Color) Color
}

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

​ Model 可以将任何 Color 转换为其自身颜色模型中的一个。转换可能会造成损失。

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var (
	RGBAModel    Model = ModelFunc(rgbaModel)
	RGBA64Model  Model = ModelFunc(rgba64Model)
	NRGBAModel   Model = ModelFunc(nrgbaModel)
	NRGBA64Model Model = ModelFunc(nrgba64Model)
	AlphaModel   Model = ModelFunc(alphaModel)
	Alpha16Model Model = ModelFunc(alpha16Model)
	GrayModel    Model = ModelFunc(grayModel)
	Gray16Model  Model = ModelFunc(gray16Model)
)

Models for the standard color types.

​ 标准颜色类型的模型。

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var CMYKModel Model = ModelFunc(cmykModel)

CMYKModel is the Model for CMYK colors.

​ CMYKModel 是 CMYK 颜色的模型。

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var NYCbCrAModel Model = ModelFunc(nYCbCrAModel)

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

​ NYCbCrAModel 是非 alpha 预乘 Y’CbCr-with-alpha 颜色的模型。

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var YCbCrModel Model = ModelFunc(yCbCrModel)

YCbCrModel is the Model for Y’CbCr colors.

​ YCbCrModel 是 Y’CbCr 颜色的模型。

func ModelFunc

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func ModelFunc(f func(Color) Color) Model

ModelFunc returns a Model that invokes f to implement the conversion.

​ ModelFunc 返回一个调用 f 来实现转换的模型。

type NRGBA

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type NRGBA struct {
	R, G, B, A uint8
}

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

​ NRGBA 表示一个非 alpha 预乘的 32 位颜色。

(NRGBA) RGBA

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func (c NRGBA) RGBA() (r, g, b, a uint32)

type NRGBA64

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type NRGBA64 struct {
	R, G, B, A uint16
}

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

​ NRGBA64 表示非预乘 alpha 的 64 位颜色，红色、绿色、蓝色和 alpha 各有 16 位。

(NRGBA64) RGBA

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func (c NRGBA64) RGBA() (r, g, b, a uint32)

type NYCbCrA <- go1.6

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type NYCbCrA struct {
	YCbCr
	A uint8
}

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

​ NYCbCrA 表示非预乘 alpha 的 Y’CbCr-with-alpha 颜色，一个亮度、两个色度和一个 alpha 分量各占 8 位。

(NYCbCrA) RGBA <- go1.6

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func (c NYCbCrA) RGBA() (uint32, uint32, uint32, uint32)

type Palette

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type Palette []Color

Palette is a palette of colors.

​ Palette 是一个颜色调色板。

(Palette) Convert

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func (p Palette) Convert(c Color) Color

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

​ Convert 返回在欧几里得 R、G、B 空间中与 c 最接近的调色板颜色。

(Palette) Index

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func (p Palette) Index(c Color) int

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

​ Index 返回与 c 在欧几里得 R、G、B、A 空间中最接近的调色板颜色的索引。

type RGBA

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type RGBA struct {
	R, G, B, A uint8
}

RGBA represents a traditional 32-bit alpha-premultiplied color, having 8 bits for each of red, green, blue and alpha.

​ RGBA 表示传统的 32 位预乘 alpha 颜色，其中红色、绿色、蓝色和 alpha 各有 8 位。

An alpha-premultiplied color component C has been scaled by alpha (A), so has valid values 0 <= C <= A.

​ 预乘 alpha 颜色分量 C 已按 alpha (A) 缩放，因此具有有效值 0 <= C <= A。

(RGBA) RGBA

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func (c RGBA) RGBA() (r, g, b, a uint32)

type RGBA64

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type RGBA64 struct {
	R, G, B, A uint16
}

RGBA64 represents a 64-bit alpha-premultiplied color, having 16 bits for each of red, green, blue and alpha.

​ RGBA64 表示 64 位预乘 alpha 颜色，其中红色、绿色、蓝色和 alpha 各有 16 位。

An alpha-premultiplied color component C has been scaled by alpha (A), so has valid values 0 <= C <= A.

​ 预乘 alpha 颜色分量 C 已按 alpha (A) 缩放，因此具有有效值 0 <= C <= A。

(RGBA64) RGBA

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func (c RGBA64) RGBA() (r, g, b, a uint32)

type YCbCr

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type YCbCr struct {
	Y, Cb, Cr uint8
}

YCbCr represents a fully opaque 24-bit Y’CbCr color, having 8 bits each for one luma and two chroma components.

​ YCbCr 表示一个完全不透明的 24 位 Y’CbCr 颜色，其中一个亮度和两个色度分量各占 8 位。

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.

​ JPEG、VP8、MPEG 系列和其他编解码器使用此颜色模型。此类编解码器通常将术语 YUV 和 Y’CbCr 互换使用，但严格来说，术语 YUV 仅适用于模拟视频信号，而 Y’（亮度）是在应用伽马校正后的 Y（亮度）。

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.

​ RGB 和 Y’CbCr 之间的转换是有损的，并且存在多种略有不同的公式可在两者之间进行转换。此软件包遵循 https://www.w3.org/Graphics/JPEG/jfif3.pdf 上的 JFIF 规范。

(YCbCr) RGBA

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func (c YCbCr) RGBA() (uint32, uint32, uint32, uint32)
最后修改 October 10, 2024: 更新 (a4b8f85)