mpegts

README

PTS/DTS/CTS

if DTS == 0 {
    // for I and P frames
	packet.Timestamp = PTS (presentation time)
} else {
    // for B frames
    packet.Timestamp = DTS (decode time)
    CTS = PTS-DTS (composition time)
}

• MPEG-TS container uses PTS and optional DTS.
• MP4 container uses DTS and CTS
• RTP container uses PTS

MPEG-TS

FFmpeg:

• PMTID=4096
• H264: PESID=256, StreamType=27, StreamID=224
• H265: PESID=256, StreamType=36, StreamID=224
• AAC: PESID=257, StreamType=15, StreamID=192

Tapo:

• PMTID=18
• H264: PESID=68, StreamType=27, StreamID=224
• AAC: PESID=69, StreamType=144, StreamID=192

Useful links

• https://github.com/theREDspace/video-onboarding/blob/main/MPEGTS%20Knowledge.md
• https://en.wikipedia.org/wiki/MPEG_transport_stream
• https://en.wikipedia.org/wiki/Program-specific_information

Documentation

Index

• Constants
• func CutOPUSPacket(b []byte) (packet []byte, left []byte)
• func StreamType(codec *core.Codec) uint8
• func TimestampToRTP(rtp *rtp.Packet, codec *core.Codec)
• func WriteTime(b []byte, t uint32)
• type Consumer
  • func NewConsumer() *Consumer
  • func (c *Consumer) AddTrack(media *core.Media, codec *core.Codec, track *core.Receiver) error
  • func (c *Consumer) WriteTo(wr io.Writer) (int64, error)
• type Demuxer
  • func NewDemuxer() *Demuxer
  • func (d *Demuxer) ReadPacket(rd io.Reader) (*rtp.Packet, error)
• type Muxer
  • func NewMuxer() *Muxer
  • func (m *Muxer) AddTrack(streamType byte) (pid uint16)
  • func (m *Muxer) GetHeader() []byte
  • func (m *Muxer) GetPayload(pid uint16, timestamp uint32, payload []byte) []byte
  • func (m *Muxer) WriteTail(wr *bits.Writer)
• type PES
  • func (p *PES) AppendBuffer(b []byte)
  • func (p *PES) GetPacket() (pkt *rtp.Packet)
  • func (p *PES) SetBuffer(size uint16, b []byte)
• type Producer
  • func Open(rd io.Reader) (*Producer, error)
  • func (c *Producer) GetTrack(media *core.Media, codec *core.Codec) (*core.Receiver, error)
  • func (c *Producer) Start() error

Constants

const (
	PacketSize = 188
	SyncByte   = 0x47  // Uppercase G
	ClockRate  = 90000 // fixed clock rate for PTS/DTS of any type
)

const (
	StreamTypeMetadata    = 0    // Reserved
	StreamTypePrivate     = 0x06 // PCMU or PCMA or FLAC from FFmpeg
	StreamTypeAAC         = 0x0F
	StreamTypeH264        = 0x1B
	StreamTypeH265        = 0x24
	StreamTypePCMATapo    = 0x90
	StreamTypePrivateOPUS = 0xEB
)

https://en.wikipedia.org/wiki/Program-specific_information#Elementary_stream_types

Functions

func CutOPUSPacket

func CutOPUSPacket(b []byte) (packet []byte, left []byte)

func StreamType

func StreamType(codec *core.Codec) uint8

func TimestampToRTP

func TimestampToRTP(rtp *rtp.Packet, codec *core.Codec)

func WriteTime

func WriteTime(b []byte, t uint32)

Types

type Consumer

type Consumer struct {
	core.Connection
	// contains filtered or unexported fields
}

func NewConsumer

func NewConsumer() *Consumer

func (*Consumer) AddTrack

func (c *Consumer) AddTrack(media *core.Media, codec *core.Codec, track *core.Receiver) error

func (*Consumer) WriteTo

func (c *Consumer) WriteTo(wr io.Writer) (int64, error)

type Demuxer

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

func NewDemuxer

func NewDemuxer() *Demuxer

func (*Demuxer) ReadPacket

func (d *Demuxer) ReadPacket(rd io.Reader) (*rtp.Packet, error)

type Muxer

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

func NewMuxer

func NewMuxer() *Muxer

func (*Muxer) AddTrack

func (m *Muxer) AddTrack(streamType byte) (pid uint16)

func (*Muxer) GetHeader

func (m *Muxer) GetHeader() []byte

func (*Muxer) GetPayload

func (m *Muxer) GetPayload(pid uint16, timestamp uint32, payload []byte) []byte

GetPayload - safe to run concurently with different pid

func (*Muxer) WriteTail

func (m *Muxer) WriteTail(wr *bits.Writer)

type PES

type PES struct {
	StreamID   byte   // from each PES header
	StreamType byte   // from PMT table
	Sequence   uint16 // manual
	Timestamp  uint32 // manual
	PTS        uint32 // from extra header, always 90000Hz
	DTS        uint32
	Payload    []byte // from PES body
	Size       int    // from PES header, can be 0
	// contains filtered or unexported fields
}

PES - Packetized Elementary Stream

func (*PES) AppendBuffer

func (p *PES) AppendBuffer(b []byte)

func (*PES) GetPacket

func (p *PES) GetPacket() (pkt *rtp.Packet)

func (*PES) SetBuffer

func (p *PES) SetBuffer(size uint16, b []byte)

type Producer

type Producer struct {
	core.Connection
	// contains filtered or unexported fields
}

func Open

func Open(rd io.Reader) (*Producer, error)

func (*Producer) GetTrack

func (c *Producer) GetTrack(media *core.Media, codec *core.Codec) (*core.Receiver, error)

func (*Producer) Start

func (c *Producer) Start() error