ffmsindex

Documentation

Overview

Package ffmsindex provides a native Go library for parsing FFMS2 Indexes, for versions post-2.23.

Index

• Constants
• type Frame
• type Header
• type Index
  • func ReadIndex(r io.Reader) (*Index, error)
• type LAVFOption
• type Track
  • func (t *Track) GetKeyframeIndices() []uint
  • func (t *Track) GetKeyframes() []uint
  • func (t *Track) GetTimestamps() []int64
• type TrackType
  • func (t TrackType) MarshalJSON() ([]byte, error)
  • func (t TrackType) String() string

Constants

const (
	TypeAudio = TrackType(1)
	TypeVideo = TrackType(0)
)

Track types

Types

type Frame

type Frame struct {
	PTS                int64
	OriginalPTS        int64
	FilePos            int64
	SampleStart        int64
	SampleCount        uint32
	OriginalPos        uint64
	PosInDecodingOrder uint64
	FrameType          int
	RepeatPict         int32
	SecondField        bool
	KeyFrame           bool
	MarkedHidden       bool
}

Frame contains all info about a particular frame or sample.

type Header

type Header struct {
	ID      uint32
	Version struct {
		Major uint8
		Minor uint8
		Micro uint8
		Bump  uint8
	}
	IndexVersion  uint16
	Tracks        uint32
	ErrorHandling uint32
	AVUtilVersion struct {
		Major uint8
		Minor uint8
		Micro uint8
	}
	AVFormatVersion struct {
		Major uint8
		Minor uint8
		Micro uint8
	}
	AVCodecVersion struct {
		Major uint8
		Minor uint8
		Micro uint8
	}
	SWScaleVersion struct {
		Major uint8
		Minor uint8
		Micro uint8
	}
	FileSize int64
	Digest   [20]byte
	LAVFOpts []LAVFOption
}

Header is the FFIndex header. It contains info on what versions of various libraries the index was generated with, and some other misc info about how it was generated.

type Index

type Index struct {
	Header *Header
	Tracks []*Track
}

Index contains all info from the parsed index.

func ReadIndex

func ReadIndex(r io.Reader) (*Index, error)

ReadIndex parses the ffindex from the reader, and returns information on all tracks and headers. Unlike FFMS2 itself, it will not fail if the libav* library versions do not match, since it is intended to extract information only.

type LAVFOption

type LAVFOption struct {
	Key   string
	Value string
}

LAVFOption is a single key-value pair for a LAVF option.

type Track

type Track struct {
	TrackType TrackType
	TimeBase  struct {
		Num int64
		Den int64
	}
	LastDuration int64
	MaxBFrames   int32
	UseDTS       bool
	HasTS        bool
	HasDiscontTS bool
	Frames       []Frame
	// contains filtered or unexported fields
}

Track contains all info about a particular track, and all of its frames.

func (*Track) GetKeyframeIndices

func (t *Track) GetKeyframeIndices() []uint

GetKeyframeIndicies gets a list of indicies that can be used in a given Track's frame slice. This differs from GetKeyframes in that it takes into account all frames, and not only visible frames. GetKeyframes would be more suitable, to, for example, use for seeking with FFMS2's API, or measuring keyframe distances.

func (*Track) GetKeyframes

func (t *Track) GetKeyframes() []uint

GetKeyframes gets a list of visible frame numbers which are keyframes. This frame number will differ from the frame number in the Frames slice, since some codecs, such as VP8, have hidden frames. This function takes those into account when calculating the frame numbers.

func (*Track) GetTimestamps

func (t *Track) GetTimestamps() []int64

GetTimestamps returns a list of timestamps for visible frames. The number of timestamps may differ from the length of the Frames slice, since some codecs, such as VP8, have hidden frames. This function takes those into account.

type TrackType

type TrackType uint8

TrackType is the type of the track

func (TrackType) MarshalJSON

func (t TrackType) MarshalJSON() ([]byte, error)

MarshalJSON is a standard implementation of JSON marshalling for the TrackType type.

func (TrackType) String

func (t TrackType) String() string