Package jpeg
import "image/jpeg"
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.
Package files
fdct.go huffman.go idct.go reader.go writer.goConstants
DefaultQuality is the default quality encoding parameter.
const DefaultQuality = 75
func Decode
func Decode(r io.Reader) (image.Image, os.Error)
Decode reads a JPEG image from r and returns it as an image.Image.
func DecodeConfig
func DecodeConfig(r io.Reader) (image.Config, os.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) os.Error
Encode writes the Image m to w in JPEG 4:2:0 baseline format with the given options. Default parameters are used if a nil *Options is passed.
type FormatError
A FormatError reports that the input is not a valid JPEG.
type FormatError string
func (FormatError) String
func (e FormatError) String() string
type Options
Options are the encoding parameters. Quality ranges from 1 to 100 inclusive, higher is better.
type Options struct {
Quality int
}
type Reader
If the passed in io.Reader does not also have ReadByte, then Decode will introduce its own buffering.
type Reader interface {
io.Reader
ReadByte() (c byte, err os.Error)
}
type UnsupportedError
An UnsupportedError reports that the input uses a valid but unimplemented JPEG feature.
type UnsupportedError string
func (UnsupportedError) String
func (e UnsupportedError) String() string