Injectable Obj-C video codecs

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/RTCEncodedImage.h>
+#import <WebRTC/RTCMacros.h>
+
+@class RTCVideoFrame;
+@class RTCEncodedImage;
+@class RTCRtpFragmentationHeader;
+
+NS_ASSUME_NONNULL_BEGIN
+
+// Implement this protocol to pass codec specific info from the encoder
+RTC_EXPORT
+@protocol RTCCodecSpecificInfo <NSObject>
+
+@end
+
+// Callback block for encoder
+typedef void (^RTCVideoEncoderCallback)(RTCEncodedImage *frame,
+                                        id<RTCCodecSpecificInfo> info,
+                                        RTCRtpFragmentationHeader *header);
+
+// Callback block for decoder
+typedef void (^RTCVideoDecoderCallback)(RTCVideoFrame *frame);
+
+// Settings for encoder
+RTC_EXPORT
+@interface RTCVideoEncoderSettings : NSObject
+
+@property(nonatomic, retain) NSString *name;
+@property(nonatomic, assign) int numberOfCores;
+
+@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;
+
+@end
+
+// Holds information to identify a codec
+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;
+- (void)initEncodeWithSettings:(RTCVideoEncoderSettings *)settings
+                      callback:(__nullable RTCVideoEncoderCallback)callback;
+- (void)releaseEncode;
+- (void)encode:(RTCVideoFrame *)frame
+    codecSpecificInfo:(id<RTCCodecSpecificInfo>)info
+           frameTypes:(NSArray<NSNumber *> *)frameTypes;
+- (BOOL)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;
+- (int32_t)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