Add support backchannel for Tapo source

This commit is contained in:
Alexey Khit
2023-02-16 11:29:10 +03:00
parent 9fd783793e
commit 70c415a1d8
8 changed files with 498 additions and 76 deletions
-6
View File
@@ -15,11 +15,5 @@ func handle(url string) (streamer.Producer, error) {
if err := conn.Dial(); err != nil {
return nil, err
}
if err := conn.Play(); err != nil {
return nil, err
}
if err := conn.Handle(); err != nil {
return nil, err
}
return conn, nil
}
+54
View File
@@ -0,0 +1,54 @@
package mpegts
var ieeeCrc32Tbl = []uint32{
0x00000000, 0xB71DC104, 0x6E3B8209, 0xD926430D, 0xDC760413, 0x6B6BC517,
0xB24D861A, 0x0550471E, 0xB8ED0826, 0x0FF0C922, 0xD6D68A2F, 0x61CB4B2B,
0x649B0C35, 0xD386CD31, 0x0AA08E3C, 0xBDBD4F38, 0x70DB114C, 0xC7C6D048,
0x1EE09345, 0xA9FD5241, 0xACAD155F, 0x1BB0D45B, 0xC2969756, 0x758B5652,
0xC836196A, 0x7F2BD86E, 0xA60D9B63, 0x11105A67, 0x14401D79, 0xA35DDC7D,
0x7A7B9F70, 0xCD665E74, 0xE0B62398, 0x57ABE29C, 0x8E8DA191, 0x39906095,
0x3CC0278B, 0x8BDDE68F, 0x52FBA582, 0xE5E66486, 0x585B2BBE, 0xEF46EABA,
0x3660A9B7, 0x817D68B3, 0x842D2FAD, 0x3330EEA9, 0xEA16ADA4, 0x5D0B6CA0,
0x906D32D4, 0x2770F3D0, 0xFE56B0DD, 0x494B71D9, 0x4C1B36C7, 0xFB06F7C3,
0x2220B4CE, 0x953D75CA, 0x28803AF2, 0x9F9DFBF6, 0x46BBB8FB, 0xF1A679FF,
0xF4F63EE1, 0x43EBFFE5, 0x9ACDBCE8, 0x2DD07DEC, 0x77708634, 0xC06D4730,
0x194B043D, 0xAE56C539, 0xAB068227, 0x1C1B4323, 0xC53D002E, 0x7220C12A,
0xCF9D8E12, 0x78804F16, 0xA1A60C1B, 0x16BBCD1F, 0x13EB8A01, 0xA4F64B05,
0x7DD00808, 0xCACDC90C, 0x07AB9778, 0xB0B6567C, 0x69901571, 0xDE8DD475,
0xDBDD936B, 0x6CC0526F, 0xB5E61162, 0x02FBD066, 0xBF469F5E, 0x085B5E5A,
0xD17D1D57, 0x6660DC53, 0x63309B4D, 0xD42D5A49, 0x0D0B1944, 0xBA16D840,
0x97C6A5AC, 0x20DB64A8, 0xF9FD27A5, 0x4EE0E6A1, 0x4BB0A1BF, 0xFCAD60BB,
0x258B23B6, 0x9296E2B2, 0x2F2BAD8A, 0x98366C8E, 0x41102F83, 0xF60DEE87,
0xF35DA999, 0x4440689D, 0x9D662B90, 0x2A7BEA94, 0xE71DB4E0, 0x500075E4,
0x892636E9, 0x3E3BF7ED, 0x3B6BB0F3, 0x8C7671F7, 0x555032FA, 0xE24DF3FE,
0x5FF0BCC6, 0xE8ED7DC2, 0x31CB3ECF, 0x86D6FFCB, 0x8386B8D5, 0x349B79D1,
0xEDBD3ADC, 0x5AA0FBD8, 0xEEE00C69, 0x59FDCD6D, 0x80DB8E60, 0x37C64F64,
0x3296087A, 0x858BC97E, 0x5CAD8A73, 0xEBB04B77, 0x560D044F, 0xE110C54B,
0x38368646, 0x8F2B4742, 0x8A7B005C, 0x3D66C158, 0xE4408255, 0x535D4351,
0x9E3B1D25, 0x2926DC21, 0xF0009F2C, 0x471D5E28, 0x424D1936, 0xF550D832,
0x2C769B3F, 0x9B6B5A3B, 0x26D61503, 0x91CBD407, 0x48ED970A, 0xFFF0560E,
0xFAA01110, 0x4DBDD014, 0x949B9319, 0x2386521D, 0x0E562FF1, 0xB94BEEF5,
0x606DADF8, 0xD7706CFC, 0xD2202BE2, 0x653DEAE6, 0xBC1BA9EB, 0x0B0668EF,
0xB6BB27D7, 0x01A6E6D3, 0xD880A5DE, 0x6F9D64DA, 0x6ACD23C4, 0xDDD0E2C0,
0x04F6A1CD, 0xB3EB60C9, 0x7E8D3EBD, 0xC990FFB9, 0x10B6BCB4, 0xA7AB7DB0,
0xA2FB3AAE, 0x15E6FBAA, 0xCCC0B8A7, 0x7BDD79A3, 0xC660369B, 0x717DF79F,
0xA85BB492, 0x1F467596, 0x1A163288, 0xAD0BF38C, 0x742DB081, 0xC3307185,
0x99908A5D, 0x2E8D4B59, 0xF7AB0854, 0x40B6C950, 0x45E68E4E, 0xF2FB4F4A,
0x2BDD0C47, 0x9CC0CD43, 0x217D827B, 0x9660437F, 0x4F460072, 0xF85BC176,
0xFD0B8668, 0x4A16476C, 0x93300461, 0x242DC565, 0xE94B9B11, 0x5E565A15,
0x87701918, 0x306DD81C, 0x353D9F02, 0x82205E06, 0x5B061D0B, 0xEC1BDC0F,
0x51A69337, 0xE6BB5233, 0x3F9D113E, 0x8880D03A, 0x8DD09724, 0x3ACD5620,
0xE3EB152D, 0x54F6D429, 0x7926A9C5, 0xCE3B68C1, 0x171D2BCC, 0xA000EAC8,
0xA550ADD6, 0x124D6CD2, 0xCB6B2FDF, 0x7C76EEDB, 0xC1CBA1E3, 0x76D660E7,
0xAFF023EA, 0x18EDE2EE, 0x1DBDA5F0, 0xAAA064F4, 0x738627F9, 0xC49BE6FD,
0x09FDB889, 0xBEE0798D, 0x67C63A80, 0xD0DBFB84, 0xD58BBC9A, 0x62967D9E,
0xBBB03E93, 0x0CADFF97, 0xB110B0AF, 0x060D71AB, 0xDF2B32A6, 0x6836F3A2,
0x6D66B4BC, 0xDA7B75B8, 0x035D36B5, 0xB440F7B1, 0x00000001,
}
func calcCRC32(crc uint32, data []byte) uint32 {
for _, b := range data {
crc = ieeeCrc32Tbl[b^byte(crc)] ^ (crc >> 8)
}
return crc
}
+8 -8
View File
@@ -14,6 +14,7 @@ const (
)
const (
StreamTypePrivate = 0x06 // PCMU or PCMA from FFmpeg
StreamTypeAAC = 0x0F
StreamTypeH264 = 0x1B
StreamTypePCMATapo = 0x90
@@ -93,7 +94,7 @@ func (p *PES) GetPacket() (pkt *rtp.Packet) {
flags := p.Payload[1]
optSize := p.Payload[2] // optional fields
p.Payload = p.Payload[minHeaderSize+optSize:]
payload := p.Payload[minHeaderSize+optSize:]
switch p.StreamType {
case StreamTypeH264:
@@ -101,7 +102,7 @@ func (p *PES) GetPacket() (pkt *rtp.Packet) {
const hasPTS = 0b1000_0000
if flags&hasPTS != 0 {
ts = uint32(ParseTime(p.Payload[minHeaderSize:]))
ts = ParseTime(p.Payload[minHeaderSize:])
}
pkt = &rtp.Packet{
@@ -109,12 +110,12 @@ func (p *PES) GetPacket() (pkt *rtp.Packet) {
PayloadType: p.StreamType,
Timestamp: ts,
},
Payload: h264.AnnexB2AVC(p.Payload),
Payload: h264.AnnexB2AVC(payload),
}
case StreamTypePCMATapo:
p.Sequence++
p.Timestamp += uint32(len(p.Payload))
p.Timestamp += uint32(len(payload))
pkt = &rtp.Packet{
Header: rtp.Header{
@@ -123,7 +124,7 @@ func (p *PES) GetPacket() (pkt *rtp.Packet) {
SequenceNumber: p.Sequence,
Timestamp: p.Timestamp,
},
Payload: p.Payload,
Payload: payload,
}
}
@@ -155,9 +156,8 @@ func (p *PES) GetPacket() (pkt *rtp.Packet) {
return
}
func ParseTime(b []byte) time.Duration {
ts := (uint64(b[0]) >> 1 & 0x7 << 30) | (uint64(b[1]) << 22) | (uint64(b[2]) >> 1 & 0x7F << 15) | (uint64(b[3]) << 7) | (uint64(b[4]) >> 1 & 0x7F)
return time.Duration(ts)
func ParseTime(b []byte) uint32 {
return (uint32(b[0]&0x0E) << 29) | (uint32(b[1]) << 22) | (uint32(b[2]&0xFE) << 14) | (uint32(b[3]) << 7) | (uint32(b[4]) >> 1)
}
func GetMedia(pkt *rtp.Packet) *streamer.Media {
+14
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@@ -0,0 +1,14 @@
package mpegts
import (
"github.com/stretchr/testify/assert"
"testing"
)
func TestTime(t *testing.T) {
w := NewWriter()
w.WriteTime(0xFFFFFFFF)
assert.Equal(t, []byte{0x27, 0xFF, 0xFF, 0xFF, 0xFF}, w.Bytes())
ts := ParseTime(w.Bytes())
assert.Equal(t, uint32(0xFFFFFFFF), ts)
}
+219
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@@ -0,0 +1,219 @@
package mpegts
type Writer struct {
b []byte // packets buffer
m int // crc start
pid []uint16
counter []byte
streamType []byte
timestamp []uint32
}
func NewWriter() *Writer {
return &Writer{}
}
func (w *Writer) AddPES(pid uint16, streamType byte) {
w.pid = append(w.pid, pid)
w.streamType = append(w.streamType, streamType)
w.counter = append(w.counter, 0)
w.timestamp = append(w.timestamp, 0)
}
func (w *Writer) WriteByte(b byte) {
w.b = append(w.b, b)
}
func (w *Writer) WriteUint16(i uint16) {
w.b = append(w.b, byte(i>>8), byte(i))
}
func (w *Writer) WriteTime(t uint32) {
const onlyPTS = 0x20
// [>>32 <<3] [>>24 <<2] [>>16 <<2] [>>8 <<1] [<<1]
w.b = append(w.b, onlyPTS|byte(t>>29)|1, byte(t>>22), byte(t>>14)|1, byte(t>>7), byte(t<<1)|1)
}
func (w *Writer) WriteBytes(b []byte) {
w.b = append(w.b, b...)
}
func (w *Writer) MarkChecksum() {
w.m = len(w.b)
}
func (w *Writer) WriteChecksum() {
crc := calcCRC32(0xFFFFFFFF, w.b[w.m:])
w.b = append(w.b, byte(crc), byte(crc>>8), byte(crc>>16), byte(crc>>24))
}
func (w *Writer) FinishPacket() {
if n := len(w.b) % PacketSize; n != 0 {
w.b = append(w.b, make([]byte, PacketSize-n)...)
}
}
func (w *Writer) Bytes() []byte {
if len(w.b)%PacketSize != 0 {
panic("wrong packet size")
}
return w.b
}
func (w *Writer) Reset() {
w.b = nil
}
const isUnitStart = 0x4000
const flagHasAdaptation = 0x20
const flagHasPayload = 0x10
const lenIsProgramTable = 0xB000
const tableFlags = 0xC1
const tableHeader = 0xE000
const tableLength = 0xF000
const patPID = 0
const patTableID = 0
const patTableExtID = 1
func (w *Writer) WritePAT() {
w.WriteByte(SyncByte)
w.WriteUint16(isUnitStart | patPID) // PAT PID
w.WriteByte(flagHasPayload) // flags...
w.WriteByte(0) // Pointer field
w.MarkChecksum()
w.WriteByte(patTableID) // Table ID
w.WriteUint16(lenIsProgramTable | 13) // Section length
w.WriteUint16(patTableExtID) // Table ID extension
w.WriteByte(tableFlags) // flags...
w.WriteByte(0) // Section number
w.WriteByte(0) // Last section number
w.WriteUint16(1) // Program num (usual 1)
w.WriteUint16(tableHeader + pmtPID)
w.WriteChecksum()
w.FinishPacket()
}
const pmtPID = 18
const pmtTableID = 2
const pmtTableExtID = 1
func (w *Writer) WritePMT() {
w.WriteByte(SyncByte)
w.WriteUint16(isUnitStart | pmtPID) // PMT PID
w.WriteByte(flagHasPayload) // flags...
w.WriteByte(0) // Pointer field
tableLen := 13 + uint16(len(w.pid))*5
w.MarkChecksum()
w.WriteByte(pmtTableID) // Table ID
w.WriteUint16(lenIsProgramTable | tableLen) // Section length
w.WriteUint16(pmtTableExtID) // Table ID extension
w.WriteByte(tableFlags) // flags...
w.WriteByte(0) // Section number
w.WriteByte(0) // Last section number
w.WriteUint16(tableHeader | w.pid[0]) // PID
w.WriteUint16(tableLength | 0) // Info length
for i, pid := range w.pid {
w.WriteByte(w.streamType[i])
w.WriteUint16(tableHeader | pid) // PID
w.WriteUint16(tableLength | 0) // Info len
}
w.WriteChecksum()
w.FinishPacket()
}
const pesHeaderSize = PacketSize - 18
func (w *Writer) WritePES(pid uint16, streamID byte, payload []byte) {
w.WriteByte(SyncByte)
w.WriteUint16(isUnitStart | pid)
// check if payload lower then max first packet size
if len(payload) < PacketSize-18 {
w.WriteByte(flagHasAdaptation | flagHasPayload)
// for 183 payload will be zero
adSize := PacketSize - 18 - 1 - byte(len(payload))
w.WriteByte(adSize)
w.WriteBytes(make([]byte, adSize))
} else {
w.WriteByte(flagHasPayload)
}
w.WriteByte(0)
w.WriteByte(0)
w.WriteByte(1)
w.WriteByte(streamID)
w.WriteUint16(uint16(8 + len(payload)))
w.WriteByte(0x80)
w.WriteByte(0x80) // only PTS
w.WriteByte(5) // optional size
switch w.streamType[0] {
case StreamTypePCMATapo:
w.timestamp[0] += uint32(len(payload) * 45 / 8)
}
w.WriteTime(w.timestamp[0])
if len(payload) < PacketSize-18 {
w.WriteBytes(payload)
return
}
w.WriteBytes(payload[:pesHeaderSize])
payload = payload[pesHeaderSize:]
var counter byte
for {
counter++
if len(payload) > PacketSize-4 {
// payload more then maximum size
w.WriteByte(SyncByte)
w.WriteUint16(pid)
w.WriteByte(flagHasPayload | counter&0xF)
w.WriteBytes(payload[:PacketSize-4])
payload = payload[PacketSize-4:]
} else if len(payload) == PacketSize-4 {
// payload equal maximum size (last packet)
w.WriteByte(SyncByte)
w.WriteUint16(pid)
w.WriteByte(flagHasPayload | counter&0xF)
w.WriteBytes(payload)
break
} else {
// payload lower than maximum size (last packet)
w.WriteByte(SyncByte)
w.WriteUint16(pid)
w.WriteByte(flagHasAdaptation | flagHasPayload | counter&0xF)
// for 183 payload will be zero
adSize := PacketSize - 4 - 1 - byte(len(payload))
w.WriteByte(adSize)
w.WriteBytes(make([]byte, adSize))
w.WriteBytes(payload)
break
}
}
}
+53
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@@ -0,0 +1,53 @@
package tapo
import (
"bytes"
"github.com/AlexxIT/go2rtc/pkg/mpegts"
"github.com/AlexxIT/go2rtc/pkg/streamer"
"github.com/pion/rtp"
"strconv"
)
func (c *Client) backchannelWriter() streamer.WriterFunc {
w := mpegts.NewWriter()
w.AddPES(68, mpegts.StreamTypePCMATapo)
w.WritePAT()
w.WritePMT()
return func(packet *rtp.Packet) (err error) {
// don't know why 68 and 192
w.WritePES(68, 192, packet.Payload)
err = c.WriteBackchannel(w.Bytes())
w.Reset()
return
}
}
func (c *Client) SetupBackchannel() (err error) {
// if conn1 is not used - we will use it for backchannel
// or we need to start another conn for session2
if c.session1 != "" {
if c.conn2, err = c.newConn(); err != nil {
return
}
} else {
c.conn2 = c.conn1
}
c.session2, err = c.Request(c.conn2, []byte(`{"params":{"talk":{"mode":"aec"},"method":"get"},"seq":3,"type":"request"}`))
return
}
func (c *Client) WriteBackchannel(body []byte) (err error) {
// TODO: fixme (size)
buf := bytes.NewBuffer(nil)
buf.WriteString("----client-stream-boundary--\r\n")
buf.WriteString("Content-Type: audio/mp2t\r\n")
buf.WriteString("X-If-Encrypt: 0\r\n")
buf.WriteString("X-Session-Id: " + c.session2 + "\r\n")
buf.WriteString("Content-Length: " + strconv.Itoa(len(body)) + "\r\n\r\n")
buf.Write(body)
_, err = buf.WriteTo(c.conn2)
return
}
+83 -59
View File
@@ -1,9 +1,11 @@
package tapo
import (
"bytes"
"crypto/aes"
"crypto/cipher"
"crypto/md5"
"encoding/json"
"errors"
"fmt"
"github.com/AlexxIT/go2rtc/pkg/mpegts"
@@ -14,7 +16,6 @@ import (
"net/http"
"net/url"
"strconv"
"strings"
)
type Client struct {
@@ -25,10 +26,13 @@ type Client struct {
medias []*streamer.Media
tracks map[byte]*streamer.Track
conn net.Conn
reader *multipart.Reader
conn1 net.Conn
conn2 net.Conn
decrypt func(b []byte) []byte
session1 string
session2 string
}
// block ciphers using cipher block chaining.
@@ -42,9 +46,14 @@ func NewClient(url string) *Client {
}
func (c *Client) Dial() (err error) {
c.conn1, err = c.newConn()
return
}
func (c *Client) newConn() (net.Conn, error) {
u, err := url.Parse(c.url)
if err != nil {
return
return nil, err
}
// support raw username/password
@@ -66,20 +75,28 @@ func (c *Client) Dial() (err error) {
req, err := http.NewRequest("POST", u.String(), nil)
if err != nil {
return
return nil, err
}
req.Header.Set("Content-Type", "multipart/mixed; boundary=--client-stream-boundary--")
res, err := tcp.Do(req)
if err != nil {
return
return nil, err
}
if res.StatusCode != http.StatusOK {
return errors.New(res.Status)
return nil, errors.New(res.Status)
}
if c.decrypt == nil {
c.newDectypter(res, username, password)
}
return res.Body.(net.Conn), nil
}
func (c *Client) newDectypter(res *http.Response, username, password string) {
// extract nonce from response
// cipher="AES_128_CBC" username="admin" padding="PKCS7_16" algorithm="MD5" nonce="***"
nonce := res.Header.Get("Key-Exchange")
@@ -106,52 +123,34 @@ func (c *Client) Dial() (err error) {
padSize := int(b[len(b)-1])
return b[:len(b)-padSize]
}
c.conn = res.Body.(net.Conn)
boundary := res.Header.Get("Content-Type")
_, boundary, _ = strings.Cut(boundary, "boundary=")
c.reader = multipart.NewReader(c.conn, boundary)
return nil
}
func (c *Client) Play() (err error) {
// audio: default, disable, enable
body := []byte(
"----client-stream-boundary--\r\n" +
"Content-Type: application/json\r\nContent-Length: 120\r\n\r\n" +
`{"params":{"preview":{"audio":["default"],"channels":[0],"resolutions":["HD"]},"method":"get"},"seq":1,"type":"request"}` +
"\r\n",
)
func (c *Client) SetupStream() (err error) {
if c.session1 != "" {
return
}
_, err = c.conn.Write(body)
return nil
// audio: default, disable, enable
c.session1, err = c.Request(c.conn1, []byte(`{"params":{"preview":{"audio":["default"],"channels":[0],"resolutions":["HD"]},"method":"get"},"seq":1,"type":"request"}`))
return
}
// Handle - first run will be in probe state
func (c *Client) Handle() error {
if c.tracks == nil {
c.tracks = map[byte]*streamer.Track{}
}
mpReader := multipart.NewReader(c.conn1, "--device-stream-boundary--")
tsReader := mpegts.NewReader()
reader := mpegts.NewReader()
probe := streamer.NewProbe(c.medias == nil)
for probe == nil || probe.Active() {
p, err := c.reader.NextRawPart()
for {
p, err := mpReader.NextRawPart()
if err != nil {
return err
}
ct := p.Header.Get("Content-Type")
if ct != "video/mp2t" {
if ct := p.Header.Get("Content-Type"); ct != "video/mp2t" {
continue
}
cl := p.Header.Get("Content-Length")
size, err := strconv.Atoi(cl)
if err != nil {
return err
@@ -169,37 +168,62 @@ func (c *Client) Handle() error {
}
body = c.decrypt(body)
reader.SetBuffer(body)
tsReader.SetBuffer(body)
for {
pkt := reader.GetPacket()
pkt := tsReader.GetPacket()
if pkt == nil {
break
}
track := c.tracks[pkt.PayloadType]
if track == nil {
// count track on probe state even if not support it
probe.Append(pkt.PayloadType)
media := mpegts.GetMedia(pkt)
if media == nil {
continue // unsupported codec
}
track = streamer.NewTrack2(media, nil)
c.medias = append(c.medias, media)
c.tracks[pkt.PayloadType] = track
if track := c.tracks[pkt.PayloadType]; track != nil {
_ = track.WriteRTP(pkt)
}
_ = track.WriteRTP(pkt)
}
}
return nil
}
func (c *Client) Close() error {
return c.conn.Close()
func (c *Client) Close() (err error) {
if c.conn1 != nil {
err = c.conn1.Close()
}
if c.conn2 != nil {
_ = c.conn2.Close()
}
return
}
func (c *Client) Request(conn net.Conn, body []byte) (string, error) {
// TODO: fixme (size)
buf := bytes.NewBuffer(nil)
buf.WriteString("----client-stream-boundary--\r\n")
buf.WriteString("Content-Type: application/json\r\n")
buf.WriteString("Content-Length: " + strconv.Itoa(len(body)) + "\r\n\r\n")
buf.Write(body)
buf.WriteString("\r\n")
if _, err := buf.WriteTo(conn); err != nil {
return "", err
}
mpReader := multipart.NewReader(conn, "--device-stream-boundary--")
for {
p, err := mpReader.NextRawPart()
if err != nil {
return "", err
}
var v struct {
Params struct {
SessionID string `json:"session_id"`
} `json:"params"`
}
if err = json.NewDecoder(p).Decode(&v); err != nil {
return "", err
}
return v.Params.SessionID, nil
}
}
+67 -3
View File
@@ -1,18 +1,82 @@
package tapo
import "github.com/AlexxIT/go2rtc/pkg/streamer"
import (
"github.com/AlexxIT/go2rtc/pkg/mpegts"
"github.com/AlexxIT/go2rtc/pkg/streamer"
)
func (c *Client) GetMedias() []*streamer.Media {
// producer should have persistent medias
if c.medias == nil {
// don't know if all Tapo has this capabilities...
c.medias = []*streamer.Media{
{
Kind: streamer.KindVideo,
Direction: streamer.DirectionSendonly,
Codecs: []*streamer.Codec{
{Name: streamer.CodecH264, ClockRate: 90000, PayloadType: streamer.PayloadTypeRAW},
},
},
{
Kind: streamer.KindAudio,
Direction: streamer.DirectionSendonly,
Codecs: []*streamer.Codec{
{Name: streamer.CodecPCMA, ClockRate: 8000, PayloadType: 8},
},
},
{
Kind: streamer.KindAudio,
Direction: streamer.DirectionRecvonly,
Codecs: []*streamer.Codec{
{Name: streamer.CodecPCMA, ClockRate: 8000, PayloadType: 8},
},
},
}
}
return c.medias
}
func (c *Client) GetTrack(media *streamer.Media, codec *streamer.Codec) *streamer.Track {
func (c *Client) GetTrack(media *streamer.Media, codec *streamer.Codec) (track *streamer.Track) {
for _, track := range c.tracks {
if track.Codec == codec {
return track
}
}
return nil
if c.tracks == nil {
c.tracks = map[byte]*streamer.Track{}
}
if media.Kind == streamer.KindVideo {
if err := c.SetupStream(); err != nil {
return nil
}
track = streamer.NewTrack2(media, codec)
c.tracks[mpegts.StreamTypeH264] = track
} else {
if media.Direction == streamer.DirectionSendonly {
if err := c.SetupStream(); err != nil {
return nil
}
track = streamer.NewTrack2(media, codec)
c.tracks[mpegts.StreamTypePCMATapo] = track
} else {
if err := c.SetupBackchannel(); err != nil {
return nil
}
if w := c.backchannelWriter(); w != nil {
track = streamer.NewTrack2(media, codec)
track.Bind(w)
c.tracks[0] = track
}
}
}
return
}
func (c *Client) Start() error {