Make OA6 codec and Enhanced RTMP configurable via debug settings

Common/Localizable.xcstrings

@@ -142545,6 +142545,12 @@
           }
         }
       }
+    },
+    "OA6 Enhanced RTMP" : {
+
+    },
+    "OA6 Video Codec" : {
+
     },
     "OBS" : {
       "localizations" : {

Moblin/Integrations/Dji/DjiDevice/DjiDevice.swift

@@ -67,6 +67,8 @@ class DjiDevice: NSObject {
     private let stopStreamingTimer = SimpleTimer(queue: .main)
     private var model: SettingsDjiDeviceModel = .unknown
     private var batteryPercentage: Int?
+    private var oa6Codec = "AVC"
+    private var oa6EnhancedRtmp = false
 
     func startLiveStream(
         wifiSsid: String,
@@ -77,7 +79,9 @@ class DjiDevice: NSObject {
         bitrate: UInt32,
         imageStabilization: SettingsDjiDeviceImageStabilization,
         deviceId: UUID,
-        model: SettingsDjiDeviceModel
+        model: SettingsDjiDeviceModel,
+        oa6Codec: String,
+        oa6EnhancedRtmp: Bool
     ) {
         logger.debug("dji-device: Start live stream for \(model)")
         self.wifiSsid = wifiSsid
@@ -89,6 +93,8 @@ class DjiDevice: NSObject {
         self.imageStabilization = imageStabilization
         self.deviceId = deviceId
         self.model = model
+        self.oa6Codec = oa6Codec
+        self.oa6EnhancedRtmp = oa6EnhancedRtmp
         reset()
         startStartStreamingTimer()
         setState(state: .discovering)
@@ -383,15 +389,17 @@ extension DjiDevice: CBPeripheralDelegate {
                                              payload: payload.encode()))
         case .osmoAction6:
             // The Osmo Action 6 uses the same JSON-wrapped start-streaming
-            // payload style as the Pocket 4 (not the legacy binary format), but
-            // pins the codec to AVC. Reverse-engineered from a BTSnoop capture of
-            // the official DJI app. This is what lets heavier image-stabilization
-            // modes stream without lag.
+            // payload style as the Pocket 4 (not the legacy binary format).
+            // Reverse-engineered from a BTSnoop capture of the official DJI app.
+            // The JSON codec and EnhancedRTMP fields are configurable via debug
+            // settings.
             let payload = DjiStartStreamingMessagePayloadOsmoAction6(
                 rtmpUrl: rtmpUrl,
                 resolution: resolution,
                 fps: fps,
-                bitrateKbps: bitrateKbps
+                bitrateKbps: bitrateKbps,
+                codec: oa6Codec,
+                enhancedRtmp: oa6EnhancedRtmp
             )
             writeMessage(message: DjiMessage(target: startStreamingTarget,
                                              id: startStreamingTransactionId,

Moblin/Integrations/Dji/DjiDevice/DjiDeviceMessage.swift

@@ -132,19 +132,11 @@ struct DjiStartStreamingMessagePayloadPocket4 {
     }
 }
 
-private struct StartStreamingPayloadOsmoAction6: Codable {
-    let rtmpAddress: String
-    let watermark: Int
-    let codec: String
-    let EnhancedRTMP: Bool
-    let supportStopLive: Bool
-}
-
 struct DjiStartStreamingMessagePayloadOsmoAction6 {
     // Same JSON-wrapped framing as the Pocket 4, but with the Osmo Action 6
-    // specific header/middle bytes and a JSON body that pins the codec to AVC
-    // (H.264) instead of HEVC. Reverse-engineered from a BTSnoop capture of the
-    // official DJI app streaming from an Osmo Action 6.
+    // specific header/middle bytes. Reverse-engineered from a BTSnoop capture of
+    // the official DJI app streaming from an Osmo Action 6. The JSON codec and
+    // EnhancedRTMP fields are configurable via debug settings.
     private static let header = Data([0x01, 0x9C, 0x00])
     private static let middle = Data([0xFE, 0x00])
     private static let padding = Data([0x00, 0x00, 0x00])
@@ -153,20 +145,32 @@ struct DjiStartStreamingMessagePayloadOsmoAction6 {
     var resolution: SettingsDjiDeviceResolution
     var bitrateKbps: UInt16
     var fps: Int
+    var codec: String
+    var enhancedRtmp: Bool
 
-    init(rtmpUrl: String, resolution: SettingsDjiDeviceResolution, fps: Int, bitrateKbps: UInt16) {
+    init(
+        rtmpUrl: String,
+        resolution: SettingsDjiDeviceResolution,
+        fps: Int,
+        bitrateKbps: UInt16,
+        codec: String,
+        enhancedRtmp: Bool
+    ) {
         self.rtmpUrl = rtmpUrl
         self.resolution = resolution
         self.fps = fps
         self.bitrateKbps = bitrateKbps
+        self.codec = codec
+        self.enhancedRtmp = enhancedRtmp
     }
 
     func encode() -> Data {
-        let payload = StartStreamingPayloadOsmoAction6(rtmpAddress: rtmpUrl,
-                                                       watermark: 0,
-                                                       codec: "AVC",
-                                                       EnhancedRTMP: false,
-                                                       supportStopLive: false)
+        let payload = StartStreamingPayload(codec: codec,
+                                            EnhancedRTMP: enhancedRtmp,
+                                            supportStopLive: false,
+                                            watermark: 0,
+                                            rtmpAddress: rtmpUrl,
+                                            orientation: "landscape")
         let data = (try? JSONEncoder().encode(payload)) ?? Data()
         let writer = ByteWriter()
         writer.writeBytes(Self.header)

Moblin/Various/Model/ModelDjiDevice.swift

@@ -159,7 +159,9 @@ extension Model {
                 bitrate: device.bitrate,
                 imageStabilization: device.imageStabilization,
                 deviceId: deviceId,
-                model: device.model
+                model: device.model,
+                oa6Codec: database.debug.djiOa6Codec.rawValue,
+                oa6EnhancedRtmp: database.debug.djiOa6EnhancedRtmp
             )
         }
         startDjiDeviceTimer(djiDeviceWrapper: djiDeviceWrapper, device: device)

Moblin/Various/Settings/SettingsDebug.swift

@@ -7,6 +7,11 @@ enum SettingsLogLevel: String, Codable, CaseIterable {
     case debug = "Debug"
 }
 
+enum SettingsDjiOa6Codec: String, Codable, CaseIterable {
+    case hevc = "HEVC"
+    case avc = "AVC"
+}
+
 let pixelFormats = ["32BGRA", "420YpCbCr8BiPlanarFullRange", "420YpCbCr8BiPlanarVideoRange"]
 let pixelFormatTypes = [
     kCVPixelFormatType_32BGRA,
@@ -51,6 +56,8 @@ class SettingsDebug: Codable, ObservableObject {
     @Published var videoBitrateChange: Bool = false
     @Published var highQualityDownsampling: Bool = false
     @Published var httpProxy: Bool = false
+    @Published var djiOa6Codec: SettingsDjiOa6Codec = .avc
+    @Published var djiOa6EnhancedRtmp: Bool = false
 
     enum CodingKeys: CodingKey {
         case logLevel
@@ -94,6 +101,8 @@ class SettingsDebug: Codable, ObservableObject {
         case videoBitrateChangeEnabled
         case highQualityDownsampling
         case httpProxy
+        case djiOa6Codec
+        case djiOa6EnhancedRtmp
     }
 
     func encode(to encoder: any Encoder) throws {
@@ -132,6 +141,8 @@ class SettingsDebug: Codable, ObservableObject {
         try container.encode(.videoBitrateChangeEnabled, videoBitrateChange)
         try container.encode(.highQualityDownsampling, highQualityDownsampling)
         try container.encode(.httpProxy, httpProxy)
+        try container.encode(.djiOa6Codec, djiOa6Codec)
+        try container.encode(.djiOa6EnhancedRtmp, djiOa6EnhancedRtmp)
     }
 
     init() {}
@@ -184,5 +195,7 @@ class SettingsDebug: Codable, ObservableObject {
         videoBitrateChange = container.decode(.videoBitrateChangeEnabled, Bool.self, false)
         highQualityDownsampling = container.decode(.highQualityDownsampling, Bool.self, false)
         httpProxy = container.decode(.httpProxy, Bool.self, false)
+        djiOa6Codec = container.decode(.djiOa6Codec, SettingsDjiOa6Codec.self, .avc)
+        djiOa6EnhancedRtmp = container.decode(.djiOa6EnhancedRtmp, Bool.self, false)
     }
 }

Moblin/View/Settings/Debug/DebugVideoSettingsView.swift

@@ -34,6 +34,14 @@ struct DebugVideoSettingsView: View {
             Section {
                 Toggle("Periodic video bitrate change", isOn: $debug.videoBitrateChange)
             }
+            Section {
+                Picker("OA6 Video Codec", selection: $debug.djiOa6Codec) {
+                    ForEach(SettingsDjiOa6Codec.allCases, id: \.self) {
+                        Text($0.rawValue)
+                    }
+                }
+                Toggle("OA6 Enhanced RTMP", isOn: $debug.djiOa6EnhancedRtmp)
+            }
         }
         .navigationTitle("Video")
     }