Add publisher initial video bitrate API

.changeset/bright-bitrates-start.md

@@ -0,0 +1,5 @@
+---
+"client-sdk-android": minor
+---
+
+Add `Room.setPublisherInitialVideoBitrate` to configure the publisher PeerConnection's current and maximum video bitrate after connecting.

livekit-android-sdk/src/main/java/io/livekit/android/room/RTCEngine.kt

@@ -443,6 +443,26 @@ internal constructor(
         return SenderTransceiverHandle(publisher, transceiver, sessionState)
     }
 
+    /**
+     * Sets the publisher PeerConnection's initial video bitrate.
+     */
+    internal suspend fun setPublisherInitialVideoBitrate(
+        initialBitrateBps: Int,
+        maxBitrateBps: Int,
+    ): Boolean {
+        require(initialBitrateBps > 0)
+        require(maxBitrateBps >= initialBitrateBps)
+
+        val publisherTransport = publisher ?: return false
+        return publisherTransport.withPeerConnection {
+            setBitrate(
+                null,
+                initialBitrateBps,
+                maxBitrateBps,
+            )
+        } == true
+    }
+
     fun updateSubscriptionPermissions(
         allParticipants: Boolean,
         participantTrackPermissions: List<ParticipantTrackPermission>,

livekit-android-sdk/src/main/java/io/livekit/android/room/Room.kt

@@ -1623,6 +1623,31 @@ constructor(
      */
     fun getPublisherRTCStats(callback: RTCStatsCollectorCallback) = engine.getPublisherRTCStats(callback)
 
+    /**
+     * Sets the local publisher's initial video bitrate.
+     *
+     * Call this after the room has connected and before or immediately after publishing video.
+     * For example:
+     * ```
+     * room.setPublisherInitialVideoBitrate(
+     *     initialBitrateBps = 1_500_000,
+     *     maxBitrateBps = 3_500_000,
+     * )
+     * ```
+     *
+     * @return `true` when WebRTC accepts the bitrate configuration, otherwise `false`.
+     * @throws IllegalArgumentException if either bitrate is invalid.
+     */
+    suspend fun setPublisherInitialVideoBitrate(
+        initialBitrateBps: Int,
+        maxBitrateBps: Int,
+    ): Boolean {
+        return engine.setPublisherInitialVideoBitrate(
+            initialBitrateBps = initialBitrateBps,
+            maxBitrateBps = maxBitrateBps,
+        )
+    }
+
     /**
      * Get stats for the subscriber peer connection.
      *

livekit-android-test/src/main/java/io/livekit/android/test/mock/MockPeerConnection.kt

@@ -46,6 +46,7 @@ class MockPeerConnection(
     private var closed = false
     var localDesc: SessionDescription? = null
     var remoteDesc: SessionDescription? = null
+    var lastBitrateSettings: Triple<Int?, Int?, Int?>? = null
 
     private val signalStateMachine = SignalStateMachine { newState ->
         observer?.onSignalingChange(newState)
@@ -210,6 +211,7 @@ class MockPeerConnection(
     }
 
     override fun setBitrate(min: Int?, current: Int?, max: Int?): Boolean {
+        lastBitrateSettings = Triple(min, current, max)
         return true
     }
 

livekit-android-test/src/test/java/io/livekit/android/room/RTCEngineMockE2ETest.kt

@@ -149,6 +149,22 @@ class RTCEngineMockE2ETest : MockE2ETest() {
         )
     }
 
+    @Test
+    fun setPublisherInitialVideoBitrate() = runTest {
+        connect()
+
+        val applied = room.setPublisherInitialVideoBitrate(
+            initialBitrateBps = 1_500_000,
+            maxBitrateBps = 3_500_000,
+        )
+
+        assertTrue(applied)
+        assertEquals(
+            Triple(null, 1_500_000, 3_500_000),
+            getPublisherPeerConnection().lastBitrateSettings,
+        )
+    }
+
     @Test
     fun iceSubscriberConnect() = runTest {
         connect()