Propagate bitrate setting to RTCRtpSender.

webrtc/examples/objc/AppRTCMobile/ARDAppClient.m

 /*
  *  Copyright 2014 The WebRTC Project Authors. All rights reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 32 matching lines @@
 static NSString * const kARDAppClientErrorDomain = @"ARDAppClient";
 static NSInteger const kARDAppClientErrorUnknown = -1;
 static NSInteger const kARDAppClientErrorRoomFull = -2;
 static NSInteger const kARDAppClientErrorCreateSDP = -3;
 static NSInteger const kARDAppClientErrorSetSDP = -4;
 static NSInteger const kARDAppClientErrorInvalidClient = -5;
 static NSInteger const kARDAppClientErrorInvalidRoom = -6;
 static NSString * const kARDMediaStreamId = @"ARDAMS";
 static NSString * const kARDAudioTrackId = @"ARDAMSa0";
 static NSString * const kARDVideoTrackId = @"ARDAMSv0";
+static NSString * const kARDVideoTrackKind = @"video";
 
 // TODO(tkchin): Add these as UI options.
 static BOOL const kARDAppClientEnableTracing = NO;
 static BOOL const kARDAppClientEnableRtcEventLog = YES;
 static int64_t const kARDAppClientAecDumpMaxSizeInBytes = 5e6;  // 5 MB.
 static int64_t const kARDAppClientRtcEventLogMaxSizeInBytes = 5e6;  // 5 MB.
+static int const kKbpsMultiplier = 1000;
 
 // We need a proxy to NSTimer because it causes a strong retain cycle. When
 // using the proxy, |invalidate| must be called before it properly deallocs.
 @interface ARDTimerProxy : NSObject
 
 - (instancetype)initWithInterval:(NSTimeInterval)interval
                          repeats:(BOOL)repeats
                     timerHandler:(void (^)(void))timerHandler;
 - (void)invalidate;
 
@@ skipping 400 matching lines @@
     [_peerConnection setLocalDescription:sdpPreferringH264
                        completionHandler:^(NSError *error) {
       ARDAppClient *strongSelf = weakSelf;
       [strongSelf peerConnection:strongSelf.peerConnection
           didSetSessionDescriptionWithError:error];
     }];
     ARDSessionDescriptionMessage *message =
         [[ARDSessionDescriptionMessage alloc]
             initWithDescription:sdpPreferringH264];
     [self sendSignalingMessage:message];
+    [self setMaxBitrateForPeerConnectionVideoSender];
   });
 }
 
 - (void)peerConnection:(RTCPeerConnection *)peerConnection
     didSetSessionDescriptionWithError:(NSError *)error {
   dispatch_async(dispatch_get_main_queue(), ^{
     if (error) {
       RTCLogError(@"Failed to set session description. Error: %@", error);
       [self disconnect];
       NSDictionary *userInfo = @{
@@ skipping 184 matching lines @@
     }];
   } else {
     [_channel sendMessage:message];
   }
 }
 
 - (RTCRtpSender *)createVideoSender {
   RTCRtpSender *sender =
       [_peerConnection senderWithKind:kRTCMediaStreamTrackKindVideo
                              streamId:kARDMediaStreamId];
-
-  [self setMaxBitrate:_maxBitrate forVideoSender:sender];
-
   RTCVideoTrack *track = [self createLocalVideoTrack];
   if (track) {
     sender.track = track;
     [_delegate appClient:self didReceiveLocalVideoTrack:track];
   }
+
   return sender;
 }
 
-- (void)setMaxBitrate:(NSNumber *)maxBitrate forVideoSender:(RTCRtpSender *)sender {
-  for (RTCRtpEncodingParameters *encoding in sender.parameters.encodings) {
-    encoding.maxBitrateBps = maxBitrate;
+- (void)setMaxBitrateForPeerConnectionVideoSender {
+  for (RTCRtpSender *sender in _peerConnection.senders) {
+    if (sender.track != nil) {
+      if ([sender.track.kind isEqualToString:kARDVideoTrackKind]) {
+        [self setMaxBitrate:_maxBitrate forVideoSender:sender];
+      }
+    }
   }
 }
 
+- (void)setMaxBitrate:(NSNumber *)maxBitrate forVideoSender:(RTCRtpSender *)sender {
+  if (maxBitrate.intValue <= 0) {
+    return;
+  }
+
+  RTCRtpParameters *parametersToModify = sender.parameters;
+  for (RTCRtpEncodingParameters *encoding in parametersToModify.encodings) {
+    encoding.maxBitrateBps = @(maxBitrate.intValue * kKbpsMultiplier);
+  }
+  [sender setParameters:parametersToModify];
+}
+
 - (RTCRtpSender *)createAudioSender {
   RTCMediaConstraints *constraints = [self defaultMediaAudioConstraints];
   RTCAudioSource *source = [_factory audioSourceWithConstraints:constraints];
   RTCAudioTrack *track = [_factory audioTrackWithSource:source
                                                 trackId:kARDAudioTrackId];
   RTCRtpSender *sender =
       [_peerConnection senderWithKind:kRTCMediaStreamTrackKindAudio
                              streamId:kARDMediaStreamId];
   sender.track = track;
   return sender;
@@ skipping 144 matching lines @@
                                          code:kARDAppClientErrorInvalidRoom
                                      userInfo:@{
         NSLocalizedDescriptionKey: @"Invalid room.",
       }];
       break;
   }
   return error;
 }
 
 @end