format: fix compatibility with some TP-Link cameras (#174)

https://github.com/aler9/rtsp-simple-server/issues/1267

pkg/format/format.go

@@ -54,6 +54,16 @@ type Format interface {
 
 // Unmarshal decodes a format from a media description.
 func Unmarshal(md *psdp.MediaDescription, payloadTypeStr string) (Format, error) {
+	if payloadTypeStr == "smart/1/90000" {
+		attr, ok := md.Attribute("rtpmap")
+		if ok {
+			i := strings.Index(attr, " TP-LINK/90000")
+			if i >= 0 {
+				payloadTypeStr = attr[:i]
+			}
+		}
+	}
+
 	tmp, err := strconv.ParseInt(payloadTypeStr, 10, 8)
 	if err != nil {
 		return nil, err

pkg/format/format_test.go

@@ -613,7 +613,7 @@ func TestNewFromMediaDescription(t *testing.T) {
 			},
 		},
 		{
-			"generic invalid rtpmap",
+			"application invalid rtpmap",
 			&psdp.MediaDescription{
 				MediaName: psdp.MediaName{
 					Media:   "application",
@@ -633,7 +633,7 @@ func TestNewFromMediaDescription(t *testing.T) {
 			},
 		},
 		{
-			"generic invalid rtpmap 2",
+			"application invalid rtpmap 2",
 			&psdp.MediaDescription{
 				MediaName: psdp.MediaName{
 					Media:   "application",
@@ -652,6 +652,27 @@ func TestNewFromMediaDescription(t *testing.T) {
 				RTPMap:     "custom/aaa",
 			},
 		},
+		{
+			"application tp-link",
+			&psdp.MediaDescription{
+				MediaName: psdp.MediaName{
+					Media:   "application",
+					Protos:  []string{"RTP", "AVP"},
+					Formats: []string{"smart/1/90000"},
+				},
+				Attributes: []psdp.Attribute{
+					{
+						Key:   "rtpmap",
+						Value: "95 TP-LINK/90000",
+					},
+				},
+			},
+			&Generic{
+				PayloadTyp: 95,
+				RTPMap:     "TP-LINK/90000",
+				ClockRat:   90000,
+			},
+		},
 	} {
 		t.Run(ca.name, func(t *testing.T) {
 			format, err := Unmarshal(ca.md, ca.md.MediaName.Formats[0])