install go2rtc on bob

2026-04-04 19:36:14 +02:00
parent f0b56e63d1
commit ccf88187b8
537 changed files with 69213 additions and 0 deletions
@@ -0,0 +1,126 @@
+package aac
+
+import (
+	"encoding/hex"
+	"fmt"
+
+	"github.com/AlexxIT/go2rtc/pkg/bits"
+	"github.com/AlexxIT/go2rtc/pkg/core"
+)
+
+const (
+	TypeAACMain = 1
+	TypeAACLC   = 2  // Low Complexity
+	TypeAACLD   = 23 // Low Delay (48000, 44100, 32000, 24000, 22050)
+	TypeESCAPE  = 31
+	TypeAACELD  = 39 // Enhanced Low Delay
+
+	AUTime = 1024
+
+	// FMTP streamtype=5 - audio stream
+	FMTP = "streamtype=5;profile-level-id=1;mode=AAC-hbr;sizelength=13;indexlength=3;indexdeltalength=3;config="
+)
+
+var sampleRates = [16]uint32{
+	96000, 88200, 64000, 48000, 44100, 32000, 24000, 22050, 16000, 12000, 11025, 8000, 7350,
+	0, 0, 0, // protection from request sampleRates[15]
+}
+
+func ConfigToCodec(conf []byte) *core.Codec {
+	// https://en.wikipedia.org/wiki/MPEG-4_Part_3#MPEG-4_Audio_Object_Types
+	rd := bits.NewReader(conf)
+
+	codec := &core.Codec{
+		FmtpLine:    FMTP + hex.EncodeToString(conf),
+		PayloadType: core.PayloadTypeRAW,
+	}
+
+	objType := rd.ReadBits(5)
+	if objType == TypeESCAPE {
+		objType = 32 + rd.ReadBits(6)
+	}
+
+	switch objType {
+	case TypeAACLC, TypeAACLD, TypeAACELD:
+		codec.Name = core.CodecAAC
+	default:
+		codec.Name = fmt.Sprintf("AAC-%X", objType)
+	}
+
+	if sampleRateIdx := rd.ReadBits8(4); sampleRateIdx < 0x0F {
+		codec.ClockRate = sampleRates[sampleRateIdx]
+	} else {
+		codec.ClockRate = rd.ReadBits(24)
+	}
+
+	codec.Channels = rd.ReadBits8(4)
+
+	return codec
+}
+
+func DecodeConfig(b []byte) (objType, sampleFreqIdx, channels byte, sampleRate uint32) {
+	rd := bits.NewReader(b)
+
+	objType = rd.ReadBits8(5)
+	if objType == 0b11111 {
+		objType = 32 + rd.ReadBits8(6)
+	}
+
+	sampleFreqIdx = rd.ReadBits8(4)
+	if sampleFreqIdx == 0b1111 {
+		sampleRate = rd.ReadBits(24)
+	} else {
+		sampleRate = sampleRates[sampleFreqIdx]
+	}
+
+	channels = rd.ReadBits8(4)
+	return
+}
+
+func EncodeConfig(objType byte, sampleRate uint32, channels byte, shortFrame bool) []byte {
+	wr := bits.NewWriter(nil)
+
+	if objType < TypeESCAPE {
+		wr.WriteBits8(objType, 5)
+	} else {
+		wr.WriteBits8(TypeESCAPE, 5)
+		wr.WriteBits8(objType-32, 6)
+	}
+
+	i := indexUint32(sampleRates[:], sampleRate)
+	if i >= 0 {
+		wr.WriteBits8(byte(i), 4)
+	} else {
+		wr.WriteBits8(0xF, 4)
+		wr.WriteBits(sampleRate, 24)
+	}
+
+	wr.WriteBits8(channels, 4)
+
+	switch objType {
+	case TypeAACLD:
+		// https://github.com/FFmpeg/FFmpeg/blob/67d392b97941bb51fb7af3a3c9387f5ab895fa46/libavcodec/aacdec_template.c#L841
+		wr.WriteBool(shortFrame)
+		wr.WriteBit(0)      // dependsOnCoreCoder
+		wr.WriteBit(0)      // extension_flag
+		wr.WriteBits8(0, 2) // ep_config
+	case TypeAACELD:
+		// https://github.com/FFmpeg/FFmpeg/blob/67d392b97941bb51fb7af3a3c9387f5ab895fa46/libavcodec/aacdec_template.c#L922
+		wr.WriteBool(shortFrame)
+		wr.WriteBits8(0, 3) // res_flags
+		wr.WriteBit(0)      // ldSbrPresentFlag
+		wr.WriteBits8(0, 4) // ELDEXT_TERM
+		wr.WriteBits8(0, 2) // ep_config
+	}
+
+	return wr.Bytes()
+}
+
+func indexUint32(s []uint32, v uint32) int {
+	for i := range s {
+		if v == s[i] {
+			return i
+		}
+	}
+	return -1
+}