vp8

Documentation

Overview

Package vp8 implements a decoder for the VP8 lossy image format.

The VP8 specification is RFC 6386.

Index

• type Decoder
  • func NewDecoder() *Decoder
  • func (d *Decoder) DecodeFrame() (*image.YCbCr, error)
  • func (d *Decoder) DecodeFrameHeader() (fh FrameHeader, err error)
  • func (d *Decoder) Init(r io.Reader, n int)
• type FrameHeader

Types

type Decoder

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

Decoder decodes VP8 bitstreams into frames. Decoding one frame consists of calling Init, DecodeFrameHeader and then DecodeFrame in that order. A Decoder can be re-used to decode multiple frames.

func NewDecoder

func NewDecoder() *Decoder

NewDecoder returns a new Decoder.

func (*Decoder) DecodeFrame

func (d *Decoder) DecodeFrame() (*image.YCbCr, error)

DecodeFrame decodes the frame and returns it as an YCbCr image. The image's contents are valid up until the next call to Decoder.Init.

func (*Decoder) DecodeFrameHeader

func (d *Decoder) DecodeFrameHeader() (fh FrameHeader, err error)

DecodeFrameHeader decodes the frame header.

func (*Decoder) Init

func (d *Decoder) Init(r io.Reader, n int)

Init initializes the decoder to read at most n bytes from r.

type FrameHeader

type FrameHeader struct {
	KeyFrame          bool
	VersionNumber     uint8
	ShowFrame         bool
	FirstPartitionLen uint32
	Width             int
	Height            int
	XScale            uint8
	YScale            uint8
}

FrameHeader is a frame header, as specified in section 9.1.