New RTCCameraVideoCapturer.

webrtc/sdk/objc/Framework/Headers/WebRTC/RTCCameraVideoCapturer.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>
+#import <WebRTC/RTCVideoCapturer.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+RTC_EXPORT
+// Camera capture that implements RTCVideoCapturer. Delivers frames to a RTCVideoCapturerDelegate
+// (usually RTCVideoSource).
+@interface RTCCameraVideoCapturer : RTCVideoCapturer
+
+// Returns list of available capture devices that support video capture.
++ (NSArray<AVCaptureDevice *> *)captureDevices;
+// Returns list of formats that are supported by this class for this device.
++ (NSArray<AVCaptureDeviceFormat *> *)supportedFormatsForDevice:(AVCaptureDevice *)device;
+
+// Starts and stops the capture session asynchronously.
+- (void)startCaptureWithDevice:(AVCaptureDevice *)device

[tkchin_webrtc, 2017/04/06 18:06:43]

This is pretty unusual. How are we supposed to change front/rear camera easily?

[sakal, 2017/04/07 10:31:38]

We wanted to add more flexibility to the application in choosing the format.
Switching camera involves enumerating capture devices and restarting the capture
with a new device.

+                        format:(AVCaptureDeviceFormat *)format
+                           fps:(int)fps;
+// Stops the capture session asynchronously.
+- (void)stopCapture;
+
+// Capture session that is used for capturing. Valid from initialization to dealloc.
+@property(readonly, nonatomic) AVCaptureSession *captureSession;

[tkchin_webrtc, 2017/04/06 18:06:43]

nit: properties before methods

[sakal, 2017/04/07 10:31:38]

Done.

+
+@end
+
+NS_ASSUME_NONNULL_END