Adding codecs to the RtpParameters returned by an RtpSender.

webrtc/api/objc/RTCRtpCodecParameters.h

+/*
+ *  Copyright 2016 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 <Foundation/Foundation.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+extern const NSString * const kRtxCodecMimeType;
+extern const NSString * const kRedCodecMimeType;
+extern const NSString * const kUlpfecCodecMimeType;
+extern const NSString * const kOpusCodecMimeType;
+extern const NSString * const kIsacCodecMimeType;
+extern const NSString * const kL16CodecMimeType;
+extern const NSString * const kG722CodecMimeType;
+extern const NSString * const kIlbcCodecMimeType;
+extern const NSString * const kPcmuCodecMimeType;
+extern const NSString * const kPcmaCodecMimeType;
+extern const NSString * const kDtmfCodecMimeType;
+extern const NSString * const kComfortNoiseCodecMimeType;
+extern const NSString * const kVp8CodecMimeType;
+extern const NSString * const kVp9CodecMimeType;
+extern const NSString * const kH264CodecMimeType;
+
+/** Defined in http://w3c.github.io/webrtc-pc/#idl-def-RTCRtpCodecParameters */
+@interface RTCRtpCodecParameters : NSObject
+
+/** The RTP payload type. */
+@property(nonatomic, assign) int payloadType;
+
+/**
+ * The codec MIME type. Valid types are listed in:
+ * http://www.iana.org/assignments/rtp-parameters/rtp-parameters.xhtml#rtp-parameters-2
+ *
+ * Several supported types are represented by the constants above.
+ */
+@property(nonatomic, nonnull) NSString *mimeType;
+
+/** The codec clock rate expressed in Hertz. */
+@property(nonatomic, assign) int clockRate;
+
+/** The number of channels (mono=1, stereo=2). */
+@property(nonatomic, assign) int channels;
+
+- (instancetype)init NS_DESIGNATED_INITIALIZER;
+
+@end
+
+NS_ASSUME_NONNULL_END