rtmp: support additional enhanced RTMP features (#4168) (#4321) (#4954)

* support reading AV1, VP9, H265, Opus, AC-3, G711, LPCM
* support reading multiple video or audio tracks at once

internal/formatprocessor/av1_test.go

@@ -0,0 +1,34 @@
+package formatprocessor
+
+import (
+	"testing"
+
+	"github.com/bluenviron/gortsplib/v4/pkg/format"
+	mcav1 "github.com/bluenviron/mediacommon/v2/pkg/codecs/av1"
+	"github.com/bluenviron/mediamtx/internal/unit"
+	"github.com/stretchr/testify/require"
+)
+
+func TestAV1RemoveTUD(t *testing.T) {
+	forma := &format.AV1{}
+
+	p, err := New(1450, forma, true, nil)
+	require.NoError(t, err)
+
+	u := &unit.AV1{
+		Base: unit.Base{
+			PTS: 30000,
+		},
+		TU: [][]byte{
+			{byte(mcav1.OBUTypeTemporalDelimiter) << 3},
+			{5},
+		},
+	}
+
+	err = p.ProcessUnit(u)
+	require.NoError(t, err)
+
+	require.Equal(t, [][]byte{
+		{5},
+	}, u.TU)
+}