diff --git a/reader.go b/reader.go
index 64e3340..ad43826 100644
--- a/reader.go
+++ b/reader.go
@@ -130,7 +130,7 @@ func ReadTSHeader(r io.Reader) (self TSHeader, err error) {
 			// clock is 27MHz
 			self.PCR = UIntToPCR(v)
 			if DebugReader {
-				fmt.Printf("ts: PCR %d %f\n", self.PCR, float64(self.PCR)/27000000)
+				fmt.Printf("ts: PCR %d %f\n", self.PCR, float64(self.PCR)/PCR_HZ)
 			}
 		}
 
@@ -533,7 +533,7 @@ func ReadPESHeader(r io.Reader) (res *PESHeader, err error) {
 		self.PTS = PESUIntToTs(v)
 
 		if DebugReader {
-			fmt.Printf("pes: pts %d %f\n", self.PTS, float64(self.PTS)/90000)
+			fmt.Printf("pes: pts %d %f\n", self.PTS, float64(self.PTS)/float64(PTS_HZ))
 		}
 	}
 
@@ -544,7 +544,7 @@ func ReadPESHeader(r io.Reader) (res *PESHeader, err error) {
 		}
 		self.DTS = PESUIntToTs(v)
 		if DebugReader {
-			fmt.Printf("pes: dts %d %f\n", self.DTS, float64(self.DTS)/90000)
+			fmt.Printf("pes: dts %d %f\n", self.DTS, float64(self.DTS)/float64(PTS_HZ))
 		}
 	}
 
diff --git a/ts.go b/ts.go
index 56a909f..10fda37 100644
--- a/ts.go
+++ b/ts.go
@@ -77,6 +77,11 @@ func PESTsToUInt(ts uint64) (v uint64) {
 	return ((ts>>30)&0x7)<<33 | ((ts>>15)&0x7fff)<<17 | (ts&0x7fff)<<1 | 0x100010001
 }
 
+const (
+	PTS_HZ = 90000
+	PCR_HZ = 27000000
+)
+
 func UIntToPCR(v uint64) uint64 {
 	// base(33)+resverd(6)+ext(9)
 	base := v>>15