Implement H264 codec in Objective-C classes.

webrtc/sdk/objc/Framework/Headers/WebRTC/RTCVideoCodec.h

 /*
  *  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 <Foundation/Foundation.h>
 
 #import <WebRTC/RTCMacros.h>
 
 @class RTCVideoFrame;
 
 NS_ASSUME_NONNULL_BEGIN
 
 /** Represents an encoded frame's type. */
 typedef NS_ENUM(NSUInteger, RTCFrameType) {
-  EmptyFrame,
-  VideoFrameKey,
-  VideoFrameDelta,
+  EmptyFrame = 0,
+  AudioFrameSpeech = 1,
+  AudioFrameCN = 2,
+  VideoFrameKey = 3,
+  VideoFrameDelta = 4,
+};
+
+typedef NS_ENUM(NSUInteger, RTCVideoContentType) {
+  Unspecified,
+  Screenshare,
 };
 
 /** Represents an encoded frame. Corresponds to webrtc::EncodedImage. */
 RTC_EXPORT
 @interface RTCEncodedImage : NSObject
 
 @property(nonatomic, retain) NSData *buffer;
 @property(nonatomic, assign) int encodedWidth;
 @property(nonatomic, assign) int encodedHeight;
 @property(nonatomic, assign) uint32_t timeStamp;
 @property(nonatomic, assign) long captureTimeMs;
 @property(nonatomic, assign) long ntpTimeMs;
 @property(nonatomic, assign) BOOL isTimingFrame;
 @property(nonatomic, assign) long encodeStartMs;
 @property(nonatomic, assign) long encodeFinishMs;
 @property(nonatomic, assign) RTCFrameType frameType;
 @property(nonatomic, assign) int rotation;
 @property(nonatomic, assign) BOOL completeFrame;
 @property(nonatomic, retain) NSNumber *qp;
+@property(nonatomic, assign) RTCVideoContentType contentType;
 
 @end
 
 /** Information for header. Corresponds to webrtc::RTPFragmentationHeader. */
 RTC_EXPORT
 @interface RTCRtpFragmentationHeader : NSObject
 
 @property(nonatomic, retain) NSArray<NSNumber *> *fragmentationOffset;
 @property(nonatomic, retain) NSArray<NSNumber *> *fragmentationLength;
 @property(nonatomic, retain) NSArray<NSNumber *> *fragmentationTimeDiff;
 @property(nonatomic, retain) NSArray<NSNumber *> *fragmentationPlType;
 
 @end
 
 /** Implement this protocol to pass codec specific info from the encoder.
  *  Corresponds to webrtc::CodecSpecificInfo.
  */
 RTC_EXPORT
 @protocol RTCCodecSpecificInfo <NSObject>
 
 @end
 
 /** Callback block for encoder. */
-typedef void (^RTCVideoEncoderCallback)(RTCEncodedImage *frame,
+typedef BOOL (^RTCVideoEncoderCallback)(RTCEncodedImage *frame,
                                         id<RTCCodecSpecificInfo> info,
                                         RTCRtpFragmentationHeader *header);
 
 /** Callback block for decoder. */
 typedef void (^RTCVideoDecoderCallback)(RTCVideoFrame *frame);
 
+typedef NS_ENUM(NSUInteger, RTCVideoCodecMode) {
+  RealtimeVideo,
+  Screensharing,
+};
+
 /** Settings for encoder. Corresponds to webrtc::VideoCodec. */
 RTC_EXPORT
 @interface RTCVideoEncoderSettings : NSObject
 
 @property(nonatomic, retain) NSString *name;
 
 @property(nonatomic, assign) unsigned short width;
 @property(nonatomic, assign) unsigned short height;
 
 @property(nonatomic, assign) unsigned int startBitrate;  // kilobits/sec.
 @property(nonatomic, assign) unsigned int maxBitrate;
 @property(nonatomic, assign) unsigned int minBitrate;
 @property(nonatomic, assign) unsigned int targetBitrate;
 
 @property(nonatomic, assign) uint32_t maxFramerate;
 
 @property(nonatomic, assign) unsigned int qpMax;
+@property(nonatomic, assign) RTCVideoCodecMode mode;
 
 @end
 
 /** Holds information to identify a codec. Corresponds to cricket::VideoCodec. */
 RTC_EXPORT
 @interface RTCVideoCodecInfo : NSObject
 
 - (instancetype)initWithPayload:(int)payload
                            name:(NSString *)name
                      parameters:(NSDictionary<NSString *, NSString *> *)parameters;
 
 @property(nonatomic, readonly) int payload;
 @property(nonatomic, readonly) NSString *name;
 @property(nonatomic, readonly) NSDictionary<NSString *, NSString *> *parameters;
 
 @end
 
 /** Protocol for encoder implementations. */
 RTC_EXPORT
 @protocol RTCVideoEncoder <NSObject>
 
 - (instancetype)initWithCodecInfo:(RTCVideoCodecInfo *)codecInfo;
 - (void)setCallback:(RTCVideoEncoderCallback)callback;
 - (int)initEncodeWithSettings:(RTCVideoEncoderSettings *)settings numberOfCores:(int)numberOfCores;
 - (int)releaseEncode;
 - (int)encode:(RTCVideoFrame *)frame
     codecSpecificInfo:(id<RTCCodecSpecificInfo>)info
            frameTypes:(NSArray<NSNumber *> *)frameTypes;
-- (BOOL)setBitrate:(uint32_t)bitrateKbit framerate:(uint32_t)framerate;
+- (int)setBitrate:(uint32_t)bitrateKbit framerate:(uint32_t)framerate;
 
 @end
 
 /** Protocol for decoder implementations. */
 RTC_EXPORT
 @protocol RTCVideoDecoder <NSObject>
 
 - (void)setCallback:(RTCVideoDecoderCallback)callback;
 - (int)initDecodeWithSettings:(RTCVideoEncoderSettings *)settings numberOfCores:(int)numberOfCores;
 - (int)releaseDecode;
 - (int)decode:(RTCEncodedImage *)encodedImage
           missingFrames:(BOOL)missingFrames
     fragmentationHeader:(RTCRtpFragmentationHeader *)fragmentationHeader
       codecSpecificInfo:(__nullable id<RTCCodecSpecificInfo>)info
            renderTimeMs:(int64_t)renderTimeMs;
 
 @end
 
 NS_ASSUME_NONNULL_END