iOS HW H264 support.

talk/examples/objc/AppRTCDemo/ARDAppClient.m

 /*
  * libjingle
  * Copyright 2014 Google Inc.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
  *
  *  1. Redistributions of source code must retain the above copyright notice,
  *     this list of conditions and the following disclaimer.
  *  2. Redistributions in binary form must reproduce the above copyright notice,
@@ skipping 24 matching lines @@
 #import "RTCMediaStream.h"
 #import "RTCPair.h"
 #import "RTCPeerConnectionInterface.h"
 #import "RTCVideoCapturer.h"
 #import "RTCAVFoundationVideoSource.h"
 
 #import "ARDAppEngineClient.h"
 #import "ARDCEODTURNClient.h"
 #import "ARDJoinResponse.h"
 #import "ARDMessageResponse.h"
+#import "ARDSDPUtils.h"
 #import "ARDSignalingMessage.h"
 #import "ARDUtilities.h"
 #import "ARDWebSocketChannel.h"
 #import "RTCICECandidate+JSON.h"
 #import "RTCSessionDescription+JSON.h"
 
 
 static NSString * const kARDDefaultSTUNServerUrl =
     @"stun:stun.l.google.com:19302";
 // TODO(tkchin): figure out a better username for CEOD statistics.
@@ skipping 282 matching lines @@
       NSDictionary *userInfo = @{
         NSLocalizedDescriptionKey: @"Failed to create session description.",
       };
       NSError *sdpError =
           [[NSError alloc] initWithDomain:kARDAppClientErrorDomain
                                      code:kARDAppClientErrorCreateSDP
                                  userInfo:userInfo];
       [_delegate appClient:self didError:sdpError];
       return;
     }
+    // Prefer H264 if available.
+    RTCSessionDescription *sdpPreferringH264 =
+        [ARDSDPUtils descriptionForDescription:sdp
+                           preferredVideoCodec:@"H264"];
     [_peerConnection setLocalDescriptionWithDelegate:self
-                                  sessionDescription:sdp];
+                                  sessionDescription:sdpPreferringH264];
     ARDSessionDescriptionMessage *message =
-        [[ARDSessionDescriptionMessage alloc] initWithDescription:sdp];
+        [[ARDSessionDescriptionMessage alloc]
+            initWithDescription:sdpPreferringH264];
     [self sendSignalingMessage:message];
   });
 }
 
 - (void)peerConnection:(RTCPeerConnection *)peerConnection
     didSetSessionDescriptionWithError:(NSError *)error {
   dispatch_async(dispatch_get_main_queue(), ^{
     if (error) {
       NSLog(@"Failed to set session description. Error: %@", error);
       [self disconnect];
@@ skipping 73 matching lines @@
 // Processes the given signaling message based on its type.
 - (void)processSignalingMessage:(ARDSignalingMessage *)message {
   NSParameterAssert(_peerConnection ||
       message.type == kARDSignalingMessageTypeBye);
   switch (message.type) {
     case kARDSignalingMessageTypeOffer:
     case kARDSignalingMessageTypeAnswer: {
       ARDSessionDescriptionMessage *sdpMessage =
           (ARDSessionDescriptionMessage *)message;
       RTCSessionDescription *description = sdpMessage.sessionDescription;
+      // Prefer H264 if available.
+      RTCSessionDescription *sdpPreferringH264 =
+          [ARDSDPUtils descriptionForDescription:description
+                             preferredVideoCodec:@"H264"];
       [_peerConnection setRemoteDescriptionWithDelegate:self
-                                     sessionDescription:description];
+                                     sessionDescription:sdpPreferringH264];
       break;
     }
     case kARDSignalingMessageTypeCandidate: {
       ARDICECandidateMessage *candidateMessage =
           (ARDICECandidateMessage *)message;
       [_peerConnection addICECandidate:candidateMessage.candidate];
       break;
     }
     case kARDSignalingMessageTypeBye:
       // Other client disconnected.
@@ skipping 177 matching lines @@
                                          code:kARDAppClientErrorInvalidRoom
                                      userInfo:@{
         NSLocalizedDescriptionKey: @"Invalid room.",
       }];
       break;
   }
   return error;
 }
 
 @end