Files
go2rtc/pkg/rtsp/helpers.go
2025-02-17 17:07:36 +03:00

135 lines
3.4 KiB
Go

package rtsp
import (
"bytes"
"io"
"net/url"
"regexp"
"strconv"
"strings"
"github.com/AlexxIT/go2rtc/pkg/core"
"github.com/pion/rtcp"
"github.com/pion/sdp/v3"
)
type RTCP struct {
Channel byte
Header rtcp.Header
Packets []rtcp.Packet
}
const sdpHeader = `v=0
o=- 0 0 IN IP4 0.0.0.0
s=-
t=0 0`
func UnmarshalSDP(rawSDP []byte) ([]*core.Media, error) {
sd := &sdp.SessionDescription{}
if err := sd.Unmarshal(rawSDP); err != nil {
// fix multiple `s=` https://github.com/AlexxIT/WebRTC/issues/417
rawSDP = regexp.MustCompile("\ns=[^\n]+").ReplaceAll(rawSDP, nil)
// fix broken `c=` https://github.com/AlexxIT/go2rtc/issues/1426
rawSDP = regexp.MustCompile("\nc=[^\n]+").ReplaceAll(rawSDP, nil)
// fix SDP header for some cameras
if i := bytes.Index(rawSDP, []byte("\nm=")); i > 0 {
rawSDP = append([]byte(sdpHeader), rawSDP[i:]...)
}
// Fix invalid media type (errSDPInvalidValue) caused by
// some TP-LINK IP camera, e.g. TL-IPC44GW
for _, b := range regexp.MustCompile("m=[^ ]+ ").FindAll(rawSDP, -1) {
switch string(b[2 : len(b)-1]) {
case "audio", "video", "application":
default:
rawSDP = bytes.Replace(rawSDP, b, []byte("m=application "), 1)
}
}
if err == io.EOF {
rawSDP = append(rawSDP, '\n')
}
sd = &sdp.SessionDescription{}
err = sd.Unmarshal(rawSDP)
if err != nil {
return nil, err
}
}
// fix buggy camera https://github.com/AlexxIT/go2rtc/issues/771
forceDirection := sd.Origin.Username == "CV-RTSPHandler"
var medias []*core.Media
for _, md := range sd.MediaDescriptions {
media := core.UnmarshalMedia(md)
// Check buggy SDP with fmtp for H264 on another track
// https://github.com/AlexxIT/WebRTC/issues/419
for _, codec := range media.Codecs {
switch codec.Name {
case core.CodecH264:
if codec.FmtpLine == "" {
codec.FmtpLine = findFmtpLine(codec.PayloadType, sd.MediaDescriptions)
}
case core.CodecH265:
if codec.FmtpLine != "" {
// all three parameters are needed for a valid fmtp line
// https://github.com/AlexxIT/go2rtc/pull/1588
if !strings.Contains(codec.FmtpLine, "sprop-vps=") ||
!strings.Contains(codec.FmtpLine, "sprop-sps=") ||
!strings.Contains(codec.FmtpLine, "sprop-pps=") {
codec.FmtpLine = ""
}
}
case core.CodecOpus:
// fix OPUS for some cameras https://datatracker.ietf.org/doc/html/rfc7587
codec.ClockRate = 48000
codec.Channels = 2
}
}
if media.Direction == "" || forceDirection {
media.Direction = core.DirectionRecvonly
}
medias = append(medias, media)
}
return medias, nil
}
func findFmtpLine(payloadType uint8, descriptions []*sdp.MediaDescription) string {
s := strconv.Itoa(int(payloadType))
for _, md := range descriptions {
codec := core.UnmarshalCodec(md, s)
if codec.FmtpLine != "" {
return codec.FmtpLine
}
}
return ""
}
// urlParse fix bugs:
// 1. Content-Base: rtsp://::ffff:192.168.1.123/onvif/profile.1/
// 2. Content-Base: rtsp://rtsp://turret2-cam.lan:554/stream1/
func urlParse(rawURL string) (*url.URL, error) {
if strings.HasPrefix(rawURL, "rtsp://rtsp://") {
rawURL = rawURL[7:]
}
u, err := url.Parse(rawURL)
if err != nil && strings.HasSuffix(err.Error(), "after host") {
if i1 := strings.Index(rawURL, "://"); i1 > 0 {
if i2 := strings.IndexByte(rawURL[i1+3:], '/'); i2 > 0 {
return urlParse(rawURL[:i1+3+i2] + ":" + rawURL[i1+3+i2:])
}
}
}
return u, err
}