diff --git a/stream/mts/encoder.go b/stream/mts/encoder.go
index abbc0fac..172a56e6 100644
--- a/stream/mts/encoder.go
+++ b/stream/mts/encoder.go
@@ -39,7 +39,7 @@ import (
 // Some common manifestations of PSI
 var (
 	// PSI struct to represent basic PAT.
-	StandardPat = psi.PSI{
+	standardPat = psi.PSI{
 		Pf:  0x00,
 		Tid: 0x00,
 		Ssi: true,
@@ -59,7 +59,7 @@ var (
 	}
 
 	// PSI struct to represent basic PMT without descriptors for time and location.
-	StandardPmt = psi.PSI{
+	standardPmt = psi.PSI{
 		Pf:  0x00,
 		Tid: 0x02,
 		Ssi: true,
@@ -83,7 +83,7 @@ var (
 	}
 
 	// Standard PMT with time and location descriptors, time and location fields are zeroed out.
-	StandardPmtTimeLocation = psi.PSI{
+	standardPmtTimeLocation = psi.PSI{
 		Pf:  0x00,
 		Tid: 0x02,
 		Ssi: true,
@@ -140,8 +140,8 @@ func SetLocation(g string) {
 }
 
 var (
-	patTable = StandardPat.Bytes()
-	pmtTable = StandardPmtTimeLocation.Bytes()
+	patTable = standardPat.Bytes()
+	pmtTable = standardPmtTimeLocation.Bytes()
 )
 
 const (