add walltime demuxer

av/pktque/walltime.go

@@ -0,0 +1,33 @@
+package pktque
+
+import (
+	"time"
+	"github.com/nareix/joy4/av"
+)
+
+type WalltimeDemuxer struct {
+	av.Demuxer
+	firsttime time.Time
+}
+
+func (self *WalltimeDemuxer) ReadPacket() (pkt av.Packet, err error) {
+	if pkt, err = self.Demuxer.ReadPacket(); err != nil {
+		return
+	}
+	if pkt.Idx == 0 {
+		if self.firsttime.IsZero() {
+			self.firsttime = time.Now()
+		}
+		pkttime := self.firsttime.Add(pkt.Time)
+		delta := pkttime.Sub(time.Now())
+		if delta > 0 {
+			time.Sleep(delta)
+		}
+	}
+	return
+}
+
+func NewWalltimeDemuxer(demuxer av.Demuxer) *WalltimeDemuxer {
+	return &WalltimeDemuxer{Demuxer: demuxer}
+}
+