Files
2025-09-16 13:10:34 +02:00

361 lines
7.0 KiB
Go

package codecprocessor
import (
"bytes"
"errors"
"time"
"github.com/bluenviron/gortsplib/v5/pkg/format"
"github.com/bluenviron/gortsplib/v5/pkg/format/rtph265"
mch265 "github.com/bluenviron/mediacommon/v2/pkg/codecs/h265"
"github.com/pion/rtp"
"github.com/bluenviron/mediamtx/internal/logger"
"github.com/bluenviron/mediamtx/internal/unit"
)
// H265-related parameters
var (
H265DefaultVPS = []byte{
0x40, 0x01, 0x0c, 0x01, 0xff, 0xff, 0x02, 0x20,
0x00, 0x00, 0x03, 0x00, 0xb0, 0x00, 0x00, 0x03,
0x00, 0x00, 0x03, 0x00, 0x7b, 0x18, 0xb0, 0x24,
}
H265DefaultSPS = []byte{
0x42, 0x01, 0x01, 0x02, 0x20, 0x00, 0x00, 0x03,
0x00, 0xb0, 0x00, 0x00, 0x03, 0x00, 0x00, 0x03,
0x00, 0x7b, 0xa0, 0x07, 0x82, 0x00, 0x88, 0x7d,
0xb6, 0x71, 0x8b, 0x92, 0x44, 0x80, 0x53, 0x88,
0x88, 0x92, 0xcf, 0x24, 0xa6, 0x92, 0x72, 0xc9,
0x12, 0x49, 0x22, 0xdc, 0x91, 0xaa, 0x48, 0xfc,
0xa2, 0x23, 0xff, 0x00, 0x01, 0x00, 0x01, 0x6a,
0x02, 0x02, 0x02, 0x01,
}
H265DefaultPPS = []byte{
0x44, 0x01, 0xc0, 0x25, 0x2f, 0x05, 0x32, 0x40,
}
)
// extract VPS, SPS and PPS without decoding RTP packets
func rtpH265ExtractParams(payload []byte) ([]byte, []byte, []byte) {
if len(payload) < 2 {
return nil, nil, nil
}
typ := mch265.NALUType((payload[0] >> 1) & 0b111111)
switch typ {
case mch265.NALUType_VPS_NUT:
return payload, nil, nil
case mch265.NALUType_SPS_NUT:
return nil, payload, nil
case mch265.NALUType_PPS_NUT:
return nil, nil, payload
case mch265.NALUType_AggregationUnit:
payload = payload[2:]
var vps []byte
var sps []byte
var pps []byte
for len(payload) > 0 {
if len(payload) < 2 {
break
}
size := uint16(payload[0])<<8 | uint16(payload[1])
payload = payload[2:]
if size == 0 {
break
}
if int(size) > len(payload) {
return nil, nil, nil
}
nalu := payload[:size]
payload = payload[size:]
typ = mch265.NALUType((nalu[0] >> 1) & 0b111111)
switch typ {
case mch265.NALUType_VPS_NUT:
vps = nalu
case mch265.NALUType_SPS_NUT:
sps = nalu
case mch265.NALUType_PPS_NUT:
pps = nalu
}
}
return vps, sps, pps
default:
return nil, nil, nil
}
}
type h265 struct {
RTPMaxPayloadSize int
Format *format.H265
GenerateRTPPackets bool
Parent logger.Writer
encoder *rtph265.Encoder
decoder *rtph265.Decoder
randomStart uint32
}
func (t *h265) initialize() error {
if t.GenerateRTPPackets {
err := t.createEncoder(nil, nil)
if err != nil {
return err
}
t.randomStart, err = randUint32()
if err != nil {
return err
}
}
return nil
}
func (t *h265) createEncoder(
ssrc *uint32,
initialSequenceNumber *uint16,
) error {
t.encoder = &rtph265.Encoder{
PayloadMaxSize: t.RTPMaxPayloadSize,
PayloadType: t.Format.PayloadTyp,
SSRC: ssrc,
InitialSequenceNumber: initialSequenceNumber,
MaxDONDiff: t.Format.MaxDONDiff,
}
return t.encoder.Init()
}
func (t *h265) updateTrackParametersFromRTPPacket(payload []byte) {
vps, sps, pps := rtpH265ExtractParams(payload)
if (vps != nil && !bytes.Equal(vps, t.Format.VPS)) ||
(sps != nil && !bytes.Equal(sps, t.Format.SPS)) ||
(pps != nil && !bytes.Equal(pps, t.Format.PPS)) {
if vps == nil {
vps = t.Format.VPS
}
if sps == nil {
sps = t.Format.SPS
}
if pps == nil {
pps = t.Format.PPS
}
t.Format.SafeSetParams(vps, sps, pps)
}
}
func (t *h265) updateTrackParametersFromAU(au [][]byte) {
vps := t.Format.VPS
sps := t.Format.SPS
pps := t.Format.PPS
update := false
for _, nalu := range au {
typ := mch265.NALUType((nalu[0] >> 1) & 0b111111)
switch typ {
case mch265.NALUType_VPS_NUT:
if !bytes.Equal(nalu, t.Format.VPS) {
vps = nalu
update = true
}
case mch265.NALUType_SPS_NUT:
if !bytes.Equal(nalu, t.Format.SPS) {
sps = nalu
update = true
}
case mch265.NALUType_PPS_NUT:
if !bytes.Equal(nalu, t.Format.PPS) {
pps = nalu
update = true
}
}
}
if update {
t.Format.SafeSetParams(vps, sps, pps)
}
}
func (t *h265) remuxAccessUnit(au [][]byte) [][]byte {
isKeyFrame := false
n := 0
for _, nalu := range au {
typ := mch265.NALUType((nalu[0] >> 1) & 0b111111)
switch typ {
case mch265.NALUType_VPS_NUT, mch265.NALUType_SPS_NUT, mch265.NALUType_PPS_NUT:
continue
case mch265.NALUType_AUD_NUT:
continue
case mch265.NALUType_IDR_W_RADL, mch265.NALUType_IDR_N_LP, mch265.NALUType_CRA_NUT:
if !isKeyFrame {
isKeyFrame = true
// prepend parameters
if t.Format.VPS != nil && t.Format.SPS != nil && t.Format.PPS != nil {
n += 3
}
}
}
n++
}
if n == 0 {
return nil
}
filteredAU := make([][]byte, n)
i := 0
if isKeyFrame && t.Format.VPS != nil && t.Format.SPS != nil && t.Format.PPS != nil {
filteredAU[0] = t.Format.VPS
filteredAU[1] = t.Format.SPS
filteredAU[2] = t.Format.PPS
i = 3
}
for _, nalu := range au {
typ := mch265.NALUType((nalu[0] >> 1) & 0b111111)
switch typ {
case mch265.NALUType_VPS_NUT, mch265.NALUType_SPS_NUT, mch265.NALUType_PPS_NUT:
continue
case mch265.NALUType_AUD_NUT:
continue
}
filteredAU[i] = nalu
i++
}
return filteredAU
}
func (t *h265) ProcessUnit(uu unit.Unit) error { //nolint:dupl
u := uu.(*unit.H265)
t.updateTrackParametersFromAU(u.AU)
u.AU = t.remuxAccessUnit(u.AU)
if u.AU != nil {
pkts, err := t.encoder.Encode(u.AU)
if err != nil {
return err
}
u.RTPPackets = pkts
for _, pkt := range u.RTPPackets {
pkt.Timestamp += t.randomStart + uint32(u.PTS)
}
}
return nil
}
func (t *h265) ProcessRTPPacket( //nolint:dupl
pkt *rtp.Packet,
ntp time.Time,
pts int64,
hasNonRTSPReaders bool,
) (unit.Unit, error) {
u := &unit.H265{
Base: unit.Base{
RTPPackets: []*rtp.Packet{pkt},
NTP: ntp,
PTS: pts,
},
}
t.updateTrackParametersFromRTPPacket(pkt.Payload)
if t.encoder == nil {
// remove padding
pkt.Padding = false
pkt.PaddingSize = 0
// RTP packets exceed maximum size: start re-encoding them
if len(pkt.Payload) > t.RTPMaxPayloadSize {
t.Parent.Log(logger.Info, "RTP packets are too big, remuxing them into smaller ones")
v1 := pkt.SSRC
v2 := pkt.SequenceNumber
err := t.createEncoder(&v1, &v2)
if err != nil {
return nil, err
}
}
}
// decode from RTP
if hasNonRTSPReaders || t.decoder != nil || t.encoder != nil {
if t.decoder == nil {
var err error
t.decoder, err = t.Format.CreateDecoder()
if err != nil {
return nil, err
}
}
au, err := t.decoder.Decode(pkt)
if t.encoder != nil {
u.RTPPackets = nil
}
if err != nil {
if errors.Is(err, rtph265.ErrNonStartingPacketAndNoPrevious) ||
errors.Is(err, rtph265.ErrMorePacketsNeeded) {
return u, nil
}
return nil, err
}
u.AU = t.remuxAccessUnit(au)
}
// route packet as is
if t.encoder == nil {
return u, nil
}
// encode into RTP
if len(u.AU) != 0 {
pkts, err := t.encoder.Encode(u.AU)
if err != nil {
return nil, err
}
u.RTPPackets = pkts
for _, newPKT := range u.RTPPackets {
newPKT.Timestamp = pkt.Timestamp
}
}
return u, nil
}