Package gif

import "image/gif"
Overview
Index

Overview ▾

包gif实现了GIF图像解码器和编码器.

GIF规范位于https://www.w3.org/Graphics/GIF/spec-gif89a.txt .

Constants

处置方法.

const (
    DisposalNone       = 0x01
    DisposalBackground = 0x02
    DisposalPrevious   = 0x03
)

func Decode

func Decode(r io.Reader) (image.Image, error)

解码从r读取GIF图像,并将第一个嵌入的图像作为image.Image返回.

func DecodeConfig

func DecodeConfig(r io.Reader) (image.Config, error)

DecodeConfig返回GIF图像的全局颜色模型和尺寸,而无需解码整个图像.

func Encode 1.2

func Encode(w io.Writer, m image.Image, o *Options) error

编码以GIF格式将图像m写入w.

func EncodeAll 1.2

func EncodeAll(w io.Writer, g *GIF) error

EncodeAll使用给定的循环计数和帧之间的延迟,以GIF格式将图像从g写入w.

type GIF

GIF表示GIF文件中可能存储的多个图像.

type GIF struct {
    Image []*image.Paletted // The successive images.
    Delay []int             // The successive delay times, one per frame, in 100ths of a second.
    // LoopCount controls the number of times an animation will be
    // restarted during display.
    // A LoopCount of 0 means to loop forever.
    // A LoopCount of -1 means to show each frame only once.
    // Otherwise, the animation is looped LoopCount+1 times.
    LoopCount int
    // Disposal is the successive disposal methods, one per frame. For
    // backwards compatibility, a nil Disposal is valid to pass to EncodeAll,
    // and implies that each frame's disposal method is 0 (no disposal
    // specified).
    Disposal []byte // Go 1.5
    // Config is the global color table (palette), width and height. A nil or
    // empty-color.Palette Config.ColorModel means that each frame has its own
    // color table and there is no global color table. Each frame's bounds must
    // be within the rectangle defined by the two points (0, 0) and
    // (Config.Width, Config.Height).
    //
    // For backwards compatibility, a zero-valued Config is valid to pass to
    // EncodeAll, and implies that the overall GIF's width and height equals
    // the first frame's bounds' Rectangle.Max point.
    Config image.Config // Go 1.5
    // BackgroundIndex is the background index in the global color table, for
    // use with the DisposalBackground disposal method.
    BackgroundIndex byte // Go 1.5
}

func DecodeAll

func DecodeAll(r io.Reader) (*GIF, error)

DecodeAll从r读取GIF图像,并返回顺序的帧和定时信息.

type Options 1.2

选项是编码参数.

type Options struct {
    // NumColors is the maximum number of colors used in the image.
    // It ranges from 1 to 256.
    NumColors int

    // Quantizer is used to produce a palette with size NumColors.
    // palette.Plan9 is used in place of a nil Quantizer.
    Quantizer draw.Quantizer

    // Drawer is used to convert the source image to the desired palette.
    // draw.FloydSteinberg is used in place of a nil Drawer.
    Drawer draw.Drawer
}

by  ICOPY.SITE