version: 1.10

package jpeg

import "image/jpeg"

Overview

Package jpeg implements a JPEG image decoder and encoder.

JPEG is defined in ITU-T T.81: http://www.w3.org/Graphics/JPEG/itu-t81.pdf.

Index

• Constants
• func Decode(r io.Reader) (image.Image, error)
• func DecodeConfig(r io.Reader) (image.Config, error)
• func Encode(w io.Writer, m image.Image, o *Options) error
• type FormatError
  • func (e FormatError) Error() string
• type Options
• type Reader
• type UnsupportedError
  • func (e UnsupportedError) Error() string

Package files

fdct.go huffman.go idct.go reader.go scan.go writer.go

Constants

const DefaultQuality = 75

DefaultQuality is the default quality encoding parameter.

func Decode
¶

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

Decode reads a JPEG image from r and returns it as an image.Image.

func DecodeConfig
¶

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

DecodeConfig returns the color model and dimensions of a JPEG image without
decoding the entire image.

func Encode
¶

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

Encode writes the Image m to w in JPEG 40 baseline format with the given
options. Default parameters are used if a nil *Options is passed.

type FormatError
¶

type FormatError string

A FormatError reports that the input is not a valid JPEG.

func (FormatError) Error
¶

func (e FormatError) Error() string

type Options
¶

type Options struct {
    Quality int
}

Options are the encoding parameters. Quality ranges from 1 to 100 inclusive,
higher is better.

type Reader
¶

type Reader interface {
    io.ByteReader
    io.Reader
}

Deprecated: Reader is deprecated.

type UnsupportedError
¶

type UnsupportedError string

An UnsupportedError reports that the input uses a valid but unimplemented JPEG
feature.

func (UnsupportedError) Error
¶

func (e UnsupportedError) Error() string