From 8399edce6ab1e51e43009464a6383e526009c73c Mon Sep 17 00:00:00 2001
From: Alex X <alexey.khit@gmail.com>
Date: Thu, 5 Sep 2024 11:58:05 +0300
Subject: [PATCH] Fix RTSP AAC audio from very buggy noname camera #1328

---
 pkg/aac/adts.go     |  1 -
 pkg/aac/rtp.go      |  9 +++++++++
 pkg/aac/rtp_test.go | 33 +++++++++++++++++++++++++++++++++
 3 files changed, 42 insertions(+), 1 deletion(-)
 create mode 100644 pkg/aac/rtp_test.go

diff --git a/pkg/aac/adts.go b/pkg/aac/adts.go
index d5e7828e..94a13ad7 100644
--- a/pkg/aac/adts.go
+++ b/pkg/aac/adts.go
@@ -9,7 +9,6 @@ import (
 )
 
 func IsADTS(b []byte) bool {
-	_ = b[1]
 	return len(b) > 7 && b[0] == 0xFF && b[1]&0xF6 == 0xF0
 }
 
diff --git a/pkg/aac/rtp.go b/pkg/aac/rtp.go
index b5ae4a10..1faa2e27 100644
--- a/pkg/aac/rtp.go
+++ b/pkg/aac/rtp.go
@@ -22,6 +22,15 @@ func RTPDepay(handler core.HandlerFunc) core.HandlerFunc {
 		//log.Printf("[RTP/AAC] units: %d, size: %4d, ts: %10d, %t", headersSize/2, len(packet.Payload), packet.Timestamp, packet.Marker)
 
 		if len(packet.Payload) < int(2+headersSize) {
+			// In very rare cases noname cameras may send data not according to the standard
+			// https://github.com/AlexxIT/go2rtc/issues/1328
+			if IsADTS(packet.Payload) {
+				clone := *packet
+				clone.Version = RTPPacketVersionAAC
+				clone.Timestamp = timestamp
+				clone.Payload = clone.Payload[ADTSHeaderSize:]
+				handler(&clone)
+			}
 			return
 		}
 
diff --git a/pkg/aac/rtp_test.go b/pkg/aac/rtp_test.go
new file mode 100644
index 00000000..c541b255
--- /dev/null
+++ b/pkg/aac/rtp_test.go
@@ -0,0 +1,33 @@
+package aac
+
+import (
+	"encoding/hex"
+	"testing"
+
+	"github.com/AlexxIT/go2rtc/pkg/core"
+	"github.com/pion/rtp"
+	"github.com/stretchr/testify/require"
+)
+
+func TestBuggy_RTSP_AAC(t *testing.T) {
+	// https: //github.com/AlexxIT/go2rtc/issues/1328
+	payload, _ := hex.DecodeString("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")
+	packet := &rtp.Packet{
+		Header: rtp.Header{
+			Version:        2,
+			Marker:         true,
+			SequenceNumber: 36944,
+			Timestamp:      4217191328,
+			SSRC:           12892774,
+		},
+		Payload: payload,
+	}
+
+	var size int
+
+	RTPDepay(func(packet *core.Packet) {
+		size = len(packet.Payload)
+	})(packet)
+
+	require.Equal(t, len(payload), size+ADTSHeaderSize)
+}