diff --git a/internal/rtmp/base/messagetype.go b/internal/rtmp/base/messagetype.go
index 17cf99b4..7f24c82a 100644
--- a/internal/rtmp/base/messagetype.go
+++ b/internal/rtmp/base/messagetype.go
@@ -10,4 +10,14 @@ const (
 	MessageTypeAcknowledge      MessageType = 3
 	MessageTypeSetWindowAckSize MessageType = 5
 	MessageTypeSetPeerBandwidth MessageType = 6
+
+	MessageTypeUserControl MessageType = 4
+
+	MessageTypeDataAMF3    MessageType = 15
+	MessageTypeCommandAMF3 MessageType = 17
+	MessageTypeDataAMF0    MessageType = 18
+	MessageTypeCommandAMF0 MessageType = 20
+
+	MessageTypeAudio MessageType = 8
+	MessageTypeVideo MessageType = 9
 )
diff --git a/internal/rtmp/conn_test.go b/internal/rtmp/conn_test.go
index 35a7bef4..845b0829 100644
--- a/internal/rtmp/conn_test.go
+++ b/internal/rtmp/conn_test.go
@@ -153,7 +153,7 @@ func TestReadTracks(t *testing.T) {
 			})
 			err = mw.Write(&base.Message{
 				ChunkStreamID: 3,
-				Type:          0x14,
+				Type:          base.MessageTypeCommandAMF0,
 				Body:          byts,
 			})
 			require.NoError(t, err)
@@ -193,7 +193,7 @@ func TestReadTracks(t *testing.T) {
 			err = c0.Read(conn, 65536)
 			require.NoError(t, err)
 			require.Equal(t, uint8(3), c0.ChunkStreamID)
-			require.Equal(t, base.MessageType(0x14), c0.Type)
+			require.Equal(t, base.MessageTypeCommandAMF0, c0.Type)
 			arr, err := flvio.ParseAMFVals(c0.Body, false)
 			require.NoError(t, err)
 			require.Equal(t, []interface{}{
@@ -224,7 +224,7 @@ func TestReadTracks(t *testing.T) {
 			// C->S releaseStream
 			err = mw.Write(&base.Message{
 				ChunkStreamID: 3,
-				Type:          0x14,
+				Type:          base.MessageTypeCommandAMF0,
 				Body: flvio.FillAMF0ValsMalloc([]interface{}{
 					"releaseStream",
 					float64(2),
@@ -237,7 +237,7 @@ func TestReadTracks(t *testing.T) {
 			// C->S FCPublish
 			err = mw.Write(&base.Message{
 				ChunkStreamID: 3,
-				Type:          0x14,
+				Type:          base.MessageTypeCommandAMF0,
 				Body: flvio.FillAMF0ValsMalloc([]interface{}{
 					"FCPublish",
 					float64(3),
@@ -250,7 +250,7 @@ func TestReadTracks(t *testing.T) {
 			// C->S createStream
 			err = mw.Write(&base.Message{
 				ChunkStreamID: 3,
-				Type:          0x14,
+				Type:          base.MessageTypeCommandAMF0,
 				Body: flvio.FillAMF0ValsMalloc([]interface{}{
 					"createStream",
 					float64(4),
@@ -263,7 +263,7 @@ func TestReadTracks(t *testing.T) {
 			err = c0.Read(conn, 65536)
 			require.NoError(t, err)
 			require.Equal(t, uint8(3), c0.ChunkStreamID)
-			require.Equal(t, base.MessageType(0x14), c0.Type)
+			require.Equal(t, base.MessageTypeCommandAMF0, c0.Type)
 			arr, err = flvio.ParseAMFVals(c0.Body, false)
 			require.NoError(t, err)
 			require.Equal(t, []interface{}{
@@ -276,7 +276,7 @@ func TestReadTracks(t *testing.T) {
 			// C->S publish
 			err = mw.Write(&base.Message{
 				ChunkStreamID:   8,
-				Type:            0x14,
+				Type:            base.MessageTypeCommandAMF0,
 				MessageStreamID: 1,
 				Body: flvio.FillAMF0ValsMalloc([]interface{}{
 					"publish",
@@ -292,7 +292,7 @@ func TestReadTracks(t *testing.T) {
 			err = c0.Read(conn, 65536)
 			require.NoError(t, err)
 			require.Equal(t, uint8(5), c0.ChunkStreamID)
-			require.Equal(t, base.MessageType(0x14), c0.Type)
+			require.Equal(t, base.MessageTypeCommandAMF0, c0.Type)
 			arr, err = flvio.ParseAMFVals(c0.Body, false)
 			require.NoError(t, err)
 			require.Equal(t, []interface{}{
@@ -333,7 +333,7 @@ func TestReadTracks(t *testing.T) {
 				})
 				err = mw.Write(&base.Message{
 					ChunkStreamID:   4,
-					Type:            0x12,
+					Type:            base.MessageTypeDataAMF0,
 					MessageStreamID: 1,
 					Body:            byts,
 				})
@@ -354,7 +354,7 @@ func TestReadTracks(t *testing.T) {
 				body := append([]byte{flvio.FRAME_KEY<<4 | flvio.VIDEO_H264, 0, 0, 0, 0}, b[:n]...)
 				err = mw.Write(&base.Message{
 					ChunkStreamID:   6,
-					Type:            flvio.TAG_VIDEO,
+					Type:            base.MessageTypeVideo,
 					MessageStreamID: 1,
 					Body:            body,
 				})
@@ -369,7 +369,7 @@ func TestReadTracks(t *testing.T) {
 				require.NoError(t, err)
 				err = mw.Write(&base.Message{
 					ChunkStreamID:   4,
-					Type:            flvio.TAG_AUDIO,
+					Type:            base.MessageTypeAudio,
 					MessageStreamID: 1,
 					Body: append([]byte{
 						flvio.SOUND_AAC<<4 | flvio.SOUND_44Khz<<2 | flvio.SOUND_16BIT<<1 | flvio.SOUND_STEREO,
@@ -400,7 +400,7 @@ func TestReadTracks(t *testing.T) {
 				})
 				err = mw.Write(&base.Message{
 					ChunkStreamID:   4,
-					Type:            0x12,
+					Type:            base.MessageTypeDataAMF0,
 					MessageStreamID: 1,
 					Body:            byts,
 				})
@@ -421,7 +421,7 @@ func TestReadTracks(t *testing.T) {
 				body := append([]byte{flvio.FRAME_KEY<<4 | flvio.VIDEO_H264, 0, 0, 0, 0}, b[:n]...)
 				err = mw.Write(&base.Message{
 					ChunkStreamID:   6,
-					Type:            flvio.TAG_VIDEO,
+					Type:            base.MessageTypeVideo,
 					MessageStreamID: 1,
 					Body:            body,
 				})
@@ -443,7 +443,7 @@ func TestReadTracks(t *testing.T) {
 				body := append([]byte{flvio.FRAME_KEY<<4 | flvio.VIDEO_H264, 0, 0, 0, 0}, b[:n]...)
 				err = mw.Write(&base.Message{
 					ChunkStreamID:   6,
-					Type:            flvio.TAG_VIDEO,
+					Type:            base.MessageTypeVideo,
 					MessageStreamID: 1,
 					Body:            body,
 				})
@@ -532,7 +532,7 @@ func TestWriteTracks(t *testing.T) {
 	})
 	err = mw.Write(&base.Message{
 		ChunkStreamID: 3,
-		Type:          0x14,
+		Type:          base.MessageTypeCommandAMF0,
 		Body:          byts,
 	})
 	require.NoError(t, err)
@@ -572,7 +572,7 @@ func TestWriteTracks(t *testing.T) {
 	err = c0.Read(conn, 65536)
 	require.NoError(t, err)
 	require.Equal(t, uint8(3), c0.ChunkStreamID)
-	require.Equal(t, base.MessageType(0x14), c0.Type)
+	require.Equal(t, base.MessageTypeCommandAMF0, c0.Type)
 	arr, err := flvio.ParseAMFVals(c0.Body, false)
 	require.NoError(t, err)
 	require.Equal(t, []interface{}{
@@ -611,7 +611,7 @@ func TestWriteTracks(t *testing.T) {
 	// C->S createStream
 	err = mw.Write(&base.Message{
 		ChunkStreamID: 3,
-		Type:          0x14,
+		Type:          base.MessageTypeCommandAMF0,
 		Body: flvio.FillAMF0ValsMalloc([]interface{}{
 			"createStream",
 			float64(2),
@@ -624,7 +624,7 @@ func TestWriteTracks(t *testing.T) {
 	err = c0.Read(conn, 65536)
 	require.NoError(t, err)
 	require.Equal(t, uint8(3), c0.ChunkStreamID)
-	require.Equal(t, base.MessageType(0x14), c0.Type)
+	require.Equal(t, base.MessageTypeCommandAMF0, c0.Type)
 	arr, err = flvio.ParseAMFVals(c0.Body, false)
 	require.NoError(t, err)
 	require.Equal(t, []interface{}{
@@ -657,7 +657,7 @@ func TestWriteTracks(t *testing.T) {
 	})
 	err = mw.Write(&base.Message{
 		ChunkStreamID: 8,
-		Type:          0x14,
+		Type:          base.MessageTypeCommandAMF0,
 		Body:          byts,
 	})
 	require.NoError(t, err)
@@ -667,7 +667,7 @@ func TestWriteTracks(t *testing.T) {
 	require.NoError(t, err)
 	require.Equal(t, base.Chunk0{
 		ChunkStreamID: base.ControlChunkStreamID,
-		Type:          4,
+		Type:          base.MessageTypeUserControl,
 		BodyLen:       6,
 		Body:          []byte{0x00, 0x04, 0x00, 0x00, 0x00, 0x01},
 	}, c0)
@@ -677,7 +677,7 @@ func TestWriteTracks(t *testing.T) {
 	require.NoError(t, err)
 	require.Equal(t, base.Chunk0{
 		ChunkStreamID: base.ControlChunkStreamID,
-		Type:          4,
+		Type:          base.MessageTypeUserControl,
 		BodyLen:       6,
 		Body:          []byte{0x00, 0x00, 0x00, 0x00, 0x00, 0x01},
 	}, c0)
@@ -686,7 +686,7 @@ func TestWriteTracks(t *testing.T) {
 	err = c0.Read(conn, 65536)
 	require.NoError(t, err)
 	require.Equal(t, uint8(5), c0.ChunkStreamID)
-	require.Equal(t, base.MessageType(0x14), c0.Type)
+	require.Equal(t, base.MessageTypeCommandAMF0, c0.Type)
 	arr, err = flvio.ParseAMFVals(c0.Body, false)
 	require.NoError(t, err)
 	require.Equal(t, []interface{}{
@@ -704,7 +704,7 @@ func TestWriteTracks(t *testing.T) {
 	err = c0.Read(conn, 65536)
 	require.NoError(t, err)
 	require.Equal(t, uint8(5), c0.ChunkStreamID)
-	require.Equal(t, base.MessageType(0x14), c0.Type)
+	require.Equal(t, base.MessageTypeCommandAMF0, c0.Type)
 	arr, err = flvio.ParseAMFVals(c0.Body, false)
 	require.NoError(t, err)
 	require.Equal(t, []interface{}{
@@ -722,7 +722,7 @@ func TestWriteTracks(t *testing.T) {
 	err = c0.Read(conn, 65536)
 	require.NoError(t, err)
 	require.Equal(t, uint8(5), c0.ChunkStreamID)
-	require.Equal(t, base.MessageType(0x14), c0.Type)
+	require.Equal(t, base.MessageTypeCommandAMF0, c0.Type)
 	arr, err = flvio.ParseAMFVals(c0.Body, false)
 	require.NoError(t, err)
 	require.Equal(t, []interface{}{
@@ -740,7 +740,7 @@ func TestWriteTracks(t *testing.T) {
 	err = c0.Read(conn, 65536)
 	require.NoError(t, err)
 	require.Equal(t, uint8(5), c0.ChunkStreamID)
-	require.Equal(t, base.MessageType(0x14), c0.Type)
+	require.Equal(t, base.MessageTypeCommandAMF0, c0.Type)
 	arr, err = flvio.ParseAMFVals(c0.Body, false)
 	require.NoError(t, err)
 	require.Equal(t, []interface{}{