1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
|
package rfc8888
import (
"time"
"github.com/pion/rtcp"
)
type packetReport struct {
arrivalTime time.Time
ecn uint8
}
// Recorder records incoming RTP packets and their arrival times. Recorder can
// be used to create feedback reports as defined by RFC 8888.
type Recorder struct {
ssrc uint32
streams map[uint32]*streamLog
}
// NewRecorder creates a new Recorder
func NewRecorder() *Recorder {
return &Recorder{
streams: map[uint32]*streamLog{},
}
}
// AddPacket writes a packet to the underlying stream.
func (r *Recorder) AddPacket(ts time.Time, ssrc uint32, seq uint16, ecn uint8) {
stream, ok := r.streams[ssrc]
if !ok {
stream = newStreamLog(ssrc)
r.streams[ssrc] = stream
}
stream.add(ts, seq, ecn)
}
// BuildReport creates a new rtcp.CCFeedbackReport containing all packets that
// were added by AddPacket and missing packets.
func (r *Recorder) BuildReport(now time.Time, maxSize int) *rtcp.CCFeedbackReport {
report := &rtcp.CCFeedbackReport{
SenderSSRC: r.ssrc,
ReportBlocks: []rtcp.CCFeedbackReportBlock{},
ReportTimestamp: ntpTime32(now),
}
maxReportBlocks := (maxSize - 12 - (8 * len(r.streams))) / 2
var maxReportBlocksPerStream int
if len(r.streams) > 1 {
maxReportBlocksPerStream = maxReportBlocks / (len(r.streams) - 1)
} else {
maxReportBlocksPerStream = maxReportBlocks
}
for i, log := range r.streams {
if len(r.streams) > 1 && int(i) == len(r.streams)-1 {
maxReportBlocksPerStream = maxReportBlocks % len(r.streams)
}
block := log.metricsAfter(now, int64(maxReportBlocksPerStream))
report.ReportBlocks = append(report.ReportBlocks, block)
}
return report
}
func ntpTime32(t time.Time) uint32 {
// seconds since 1st January 1900
s := (float64(t.UnixNano()) / 1000000000.0) + 2208988800
integerPart := uint32(s)
fractionalPart := uint32((s - float64(integerPart)) * 0xFFFFFFFF)
// higher 32 bits are the integer part, lower 32 bits are the fractional part
return uint32(((uint64(integerPart)<<32 | uint64(fractionalPart)) >> 16) & 0xFFFFFFFF)
}
|
