BWE allocation strategy allows controlling of bitrate allocation with WEBRTC external logic.

This CL implements the main logic and IOS appRTC integration.

Unit tests and Android appRTC will be in separate CL.

Bug: webrtc:8243
Change-Id: If8e5195294046a47316e9fade1b0dfec211155e1
Reviewed-on: https://webrtc-review.googlesource.com/4860
Commit-Queue: Alex Narest <alexnarest@webrtc.org>
Reviewed-by: Niels Moller <nisse@webrtc.org>
Reviewed-by: Stefan Holmer <stefan@webrtc.org>
Reviewed-by: Taylor Brandstetter <deadbeef@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#20329}

sdk/objc/Framework/Classes/PeerConnection/RTCBitrateAllocationStrategy.mm

@@ -0,0 +1,28 @@
+/*
+ *  Copyright 2017 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.
+ */
+
+#import "WebRTC/RTCBitrateAllocationStrategy.h"
+
+#include "rtc_base/bitrateallocationstrategy.h"
+#include "rtc_base/checks.h"
+
+@implementation RTCBitrateAllocationStrategy
+
+@synthesize strategy = _strategy;
+
+- (instancetype)initWith:(rtc::BitrateAllocationStrategy*)strategy {
+  RTC_DCHECK(strategy);
+  if (self = [super init]) {
+    _strategy = strategy;
+  }
+  return self;
+}
+
+@end

sdk/objc/Framework/Classes/PeerConnection/RTCConfiguration.mm

@@ -178,7 +178,6 @@
     nativeConfig->ice_regather_interval_range =
         rtc::Optional<rtc::IntervalRange>(*nativeIntervalRange);
   }
-
   return nativeConfig.release();
 }
 

sdk/objc/Framework/Classes/PeerConnection/RTCPeerConnection.mm

@@ -21,6 +21,7 @@
 #import "RTCRtpReceiver+Private.h"
 #import "RTCRtpSender+Private.h"
 #import "RTCSessionDescription+Private.h"
+#import "WebRTC/RTCBitrateAllocationStrategy.h"
 #import "WebRTC/RTCLogging.h"
 
 #include <memory>
@@ -385,6 +386,15 @@ void PeerConnectionDelegateAdapter::OnIceCandidatesRemoved(
   return _peerConnection->SetBitrate(params).ok();
 }
 
+- (void)setBitrateAllocationStrategy:
+        (RTCBitrateAllocationStrategy *_Nullable)bitrateAllocationStrategy {
+  if (bitrateAllocationStrategy)
+    _peerConnection->SetBitrateAllocationStrategy(
+        std::unique_ptr<rtc::BitrateAllocationStrategy>(bitrateAllocationStrategy.strategy));
+  else
+    _peerConnection->SetBitrateAllocationStrategy(nullptr);
+}
+
 - (BOOL)startRtcEventLogWithFilePath:(NSString *)filePath
                       maxSizeInBytes:(int64_t)maxSizeInBytes {
   RTC_DCHECK(filePath.length);

sdk/objc/Framework/Headers/WebRTC/RTCBitrateAllocationStrategy.h

@@ -0,0 +1,32 @@
+/*
+ *  Copyright 2017 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.
+ */
+
+#import <WebRTC/RTCMacros.h>
+#import <WebRTC/RTCMediaStreamTrack.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+namespace rtc {
+
+class BitrateAllocationStrategy;
+}
+
+RTC_EXPORT
+@interface RTCBitrateAllocationStrategy : NSObject
+
+- (instancetype)init NS_UNAVAILABLE;
+- (instancetype)initWith:(rtc::BitrateAllocationStrategy*)strategy;
+
+/** Native bitrate allocation strategy. */
+@property(nonatomic, readonly) rtc::BitrateAllocationStrategy* strategy;
+
+@end
+
+NS_ASSUME_NONNULL_END

sdk/objc/Framework/Headers/WebRTC/RTCPeerConnection.h

@@ -24,6 +24,7 @@
 @class RTCRtpSender;
 @class RTCSessionDescription;
 @class RTCLegacyStatsReport;
+@class RTCBitrateAllocationStrategy;
 
 NS_ASSUME_NONNULL_BEGIN
 
@@ -193,6 +194,13 @@ RTC_EXPORT
           currentBitrateBps:(nullable NSNumber *)currentBitrateBps
               maxBitrateBps:(nullable NSNumber *)maxBitrateBps;
 
+/** Sets current strategy. If not set default WebRTC allocator will be used.
+ *   May be changed during an active session. The strategy
+ *   ownership is passed with std::unique_ptr
+ */
+- (void)setBitrateAllocationStrategy:
+        (RTCBitrateAllocationStrategy *_Nullable)bitrateAllocationStrategy;
+
 /** Start or stop recording an Rtc EventLog. */
 - (BOOL)startRtcEventLogWithFilePath:(NSString *)filePath
                       maxSizeInBytes:(int64_t)maxSizeInBytes;