qoi

README

QOI - The “Quite OK Image” format for fast, lossless image compression - in Go

Fork of xfmoulet/qoi with changes to allow buffer reuse. See qoi.DecodeIntoBuffer(). The version in this repository will also:

• omit the alpha channel if it is not present when decoding.
• omit the alpha channel if it is not present or not used (all alpha values =100%) when encoding.
• write un-premultiplied instead of premultiplied values. (in accordance with QOI specification)

See qoi.h for format specification.

More info at https://qoiformat.org/

Documentation

Index

• func DecodeConfig(reader io.Reader) (cfg image.Config, err error)
• func Encode(w io.Writer, img image.Image) error
• type Colorspace
• type Header
  • func DecodeHeader(r io.Reader) (header Header, err error)
• type Image
  • func Decode(reader io.Reader) (*Image, error)
  • func DecodeIntoBuffer(r io.Reader, dest []byte) (*Image, error)
  • func (img *Image) At(x, y int) color.Color
  • func (img *Image) Bounds() image.Rectangle
  • func (img *Image) ColorModel() color.Model

Functions

func DecodeConfig

func DecodeConfig(reader io.Reader) (cfg image.Config, err error)

func Encode

func Encode(w io.Writer, img image.Image) error

Encode encodes img as a QOI file and writes it to w.

Types

type Colorspace

type Colorspace uint8

const (
	SRGB   Colorspace = 0
	Linear Colorspace = 1
)

type Header

type Header struct {
	// contains filtered or unexported fields
}

func DecodeHeader

func DecodeHeader(r io.Reader) (header Header, err error)

DecodeHeader decodes only the header from the beginning of a QOI image and returns it, if it is valid.

type Image

type Image struct {
	Pix        []byte
	Width      int
	Height     int
	Channels   uint8
	Colorspace Colorspace
}

func Decode

func Decode(reader io.Reader) (*Image, error)

func DecodeIntoBuffer

func DecodeIntoBuffer(r io.Reader, dest []byte) (*Image, error)

Decode decodes QOI image data from r into dest, until all pixels are written. If dest cannot fit the image, an error is returned.

func (*Image) At

func (img *Image) At(x, y int) color.Color

func (*Image) Bounds

func (img *Image) Bounds() image.Rectangle

func (*Image) ColorModel

func (img *Image) ColorModel() color.Model