Split avfoundationcapturer classes in separate files.

webrtc/sdk/objc/Framework/Classes/RTCAVFoundationVideoCapturerInternal.mm

Index: webrtc/sdk/objc/Framework/Classes/RTCAVFoundationVideoCapturerInternal.mm
diff --git a/webrtc/sdk/objc/Framework/Classes/avfoundationvideocapturer.mm b/webrtc/sdk/objc/Framework/Classes/RTCAVFoundationVideoCapturerInternal.mm
similarity index 43%
copy from webrtc/sdk/objc/Framework/Classes/avfoundationvideocapturer.mm
copy to webrtc/sdk/objc/Framework/Classes/RTCAVFoundationVideoCapturerInternal.mm
index 49b56817277fdc86a015fe8cc888220c4657c2c8..5c276fc254aa73f79f618d95899903ddd588ebbe 100644
--- a/webrtc/sdk/objc/Framework/Classes/avfoundationvideocapturer.mm
+++ b/webrtc/sdk/objc/Framework/Classes/RTCAVFoundationVideoCapturerInternal.mm
@@ -1,5 +1,5 @@
 /*
- *  Copyright 2015 The WebRTC project authors. All Rights Reserved.
+ *  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
@@ -8,9 +8,8 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
-#include "avfoundationvideocapturer.h"
+#import "RTCAVFoundationVideoCapturerInternal.h"
 
-#import <AVFoundation/AVFoundation.h>
 #import <Foundation/Foundation.h>
 #if TARGET_OS_IPHONE
 #import <UIKit/UIKit.h>
@@ -18,176 +17,8 @@
 
 #import "RTCDispatcher+Private.h"
 #import "WebRTC/RTCLogging.h"
-#if TARGET_OS_IPHONE
-#import "WebRTC/UIDevice+RTCDevice.h"
-#endif
-
-#include "libyuv/rotate.h"
-
-#include "webrtc/base/bind.h"
-#include "webrtc/base/checks.h"
-#include "webrtc/base/logging.h"
-#include "webrtc/base/thread.h"
-#include "webrtc/common_video/include/corevideo_frame_buffer.h"
-#include "webrtc/common_video/rotation.h"
-
-// TODO(denicija): add support for higher frame rates.
-// See http://crbug/webrtc/6355 for more info.
-static const int kFramesPerSecond = 30;
-
-static inline BOOL IsMediaSubTypeSupported(FourCharCode mediaSubType) {
-  return (mediaSubType == kCVPixelFormatType_420YpCbCr8PlanarFullRange ||
-          mediaSubType == kCVPixelFormatType_420YpCbCr8BiPlanarVideoRange);
-}
-
-static inline BOOL IsFrameRateWithinRange(int fps, AVFrameRateRange *range) {
-  return range.minFrameRate <= fps && range.maxFrameRate >= fps;
-}
-
-// Returns filtered array of device formats based on predefined constraints our
-// stack imposes.
-static NSArray<AVCaptureDeviceFormat *> *GetEligibleDeviceFormats(
-    const AVCaptureDevice *device,
-    int supportedFps) {
-  NSMutableArray<AVCaptureDeviceFormat *> *eligibleDeviceFormats =
-      [NSMutableArray array];
-
-  for (AVCaptureDeviceFormat *format in device.formats) {
-    // Filter out subTypes that we currently don't support in the stack
-    FourCharCode mediaSubType =
-        CMFormatDescriptionGetMediaSubType(format.formatDescription);
-    if (!IsMediaSubTypeSupported(mediaSubType)) {
-      continue;
-    }
-
-    // Filter out frame rate ranges that we currently don't support in the stack
-    for (AVFrameRateRange *frameRateRange in format.videoSupportedFrameRateRanges) {
-      if (IsFrameRateWithinRange(supportedFps, frameRateRange)) {
-        [eligibleDeviceFormats addObject:format];
-        break;
-      }
-    }
-  }
-
-  return [eligibleDeviceFormats copy];
-}
-
-// Mapping from cricket::VideoFormat to AVCaptureDeviceFormat.
-static AVCaptureDeviceFormat *GetDeviceFormatForVideoFormat(
-    const AVCaptureDevice *device,
-    const cricket::VideoFormat &videoFormat) {
-  AVCaptureDeviceFormat *desiredDeviceFormat = nil;
-  NSArray<AVCaptureDeviceFormat *> *eligibleFormats =
-      GetEligibleDeviceFormats(device, videoFormat.framerate());
-
-  for (AVCaptureDeviceFormat *deviceFormat in eligibleFormats) {
-    CMVideoDimensions dimension =
-        CMVideoFormatDescriptionGetDimensions(deviceFormat.formatDescription);
-    FourCharCode mediaSubType =
-        CMFormatDescriptionGetMediaSubType(deviceFormat.formatDescription);
-
-    if (videoFormat.width == dimension.width &&
-        videoFormat.height == dimension.height) {
-      if (mediaSubType == kCVPixelFormatType_420YpCbCr8BiPlanarFullRange) {
-        // This is the preferred format so no need to wait for better option.
-        return deviceFormat;
-      } else {
-        // This is good candidate, but let's wait for something better.
-        desiredDeviceFormat = deviceFormat;
-      }
-    }
-  }
-
-  return desiredDeviceFormat;
-}
 
-// Mapping from AVCaptureDeviceFormat to cricket::VideoFormat for given input
-// device.
-static std::set<cricket::VideoFormat> GetSupportedVideoFormatsForDevice(
-    AVCaptureDevice *device) {
-  std::set<cricket::VideoFormat> supportedFormats;
-
-  NSArray<AVCaptureDeviceFormat *> *eligibleFormats =
-      GetEligibleDeviceFormats(device, kFramesPerSecond);
-
-  for (AVCaptureDeviceFormat *deviceFormat in eligibleFormats) {
-    CMVideoDimensions dimension =
-        CMVideoFormatDescriptionGetDimensions(deviceFormat.formatDescription);
-    cricket::VideoFormat format = cricket::VideoFormat(
-        dimension.width, dimension.height,
-        cricket::VideoFormat::FpsToInterval(kFramesPerSecond),
-        cricket::FOURCC_NV12);
-    supportedFormats.insert(format);
-  }
-
-  return supportedFormats;
-}
-
-// Sets device format for the provided capture device. Returns YES/NO depending on success.
-// TODO(denicija): When this file is split this static method should be reconsidered.
-// Perhaps adding a category on AVCaptureDevice would be better.
-static BOOL SetFormatForCaptureDevice(AVCaptureDevice *device,
-                                      AVCaptureSession *session,
-                                      const cricket::VideoFormat &format) {
-  AVCaptureDeviceFormat *deviceFormat =
-      GetDeviceFormatForVideoFormat(device, format);
-  const int fps = cricket::VideoFormat::IntervalToFps(format.interval);
-
-  NSError *error = nil;
-  BOOL success = YES;
-  [session beginConfiguration];
-  if ([device lockForConfiguration:&error]) {
-    @try {
-      device.activeFormat = deviceFormat;
-      device.activeVideoMinFrameDuration = CMTimeMake(1, fps);
-    } @catch (NSException *exception) {
-      RTCLogError(
-          @"Failed to set active format!\n User info:%@",
-          exception.userInfo);
-      success = NO;
-    }
-
-    [device unlockForConfiguration];
-  } else {
-    RTCLogError(
-        @"Failed to lock device %@. Error: %@",
-        device, error.userInfo);
-    success = NO;
-  }
-  [session commitConfiguration];
-
-  return success;
-}
-
-// This class used to capture frames using AVFoundation APIs on iOS. It is meant
-// to be owned by an instance of AVFoundationVideoCapturer. The reason for this
-// because other webrtc objects own cricket::VideoCapturer, which is not
-// ref counted. To prevent bad behavior we do not expose this class directly.
-@interface RTCAVFoundationVideoCapturerInternal : NSObject
-    <AVCaptureVideoDataOutputSampleBufferDelegate>
-
-@property(nonatomic, readonly) AVCaptureSession *captureSession;
-@property(nonatomic, readonly) dispatch_queue_t frameQueue;
-@property(nonatomic, readonly) BOOL canUseBackCamera;
-@property(nonatomic, assign) BOOL useBackCamera;  // Defaults to NO.
-@property(atomic, assign) BOOL isRunning;  // Whether the capture session is running.
-@property(atomic, assign) BOOL hasStarted;  // Whether we have an unmatched start.
-
-// We keep a pointer back to AVFoundationVideoCapturer to make callbacks on it
-// when we receive frames. This is safe because this object should be owned by
-// it.
-- (instancetype)initWithCapturer:(webrtc::AVFoundationVideoCapturer *)capturer;
-- (AVCaptureDevice *)getActiveCaptureDevice;
-
-- (nullable AVCaptureDevice *)frontCaptureDevice;
-- (nullable AVCaptureDevice *)backCaptureDevice;
-
-// Starts and stops the capture session asynchronously. We cannot do this
-// synchronously without blocking a WebRTC thread.
-- (void)start;
-- (void)stop;
-
-@end
+#include "avfoundationformatmapper.h"
 
 @implementation RTCAVFoundationVideoCapturerInternal {
   // Keep pointers to inputs for convenience.
@@ -272,22 +103,20 @@ static BOOL SetFormatForCaptureDevice(AVCaptureDevice *device,
   return self.useBackCamera ? _backCameraInput.device : _frontCameraInput.device;
 }
 
-- (AVCaptureDevice *)frontCaptureDevice {
+- (nullable AVCaptureDevice *)frontCaptureDevice {
   return _frontCameraInput.device;
 }
 
-- (AVCaptureDevice *)backCaptureDevice {
+- (nullable AVCaptureDevice *)backCaptureDevice {
   return _backCameraInput.device;
 }
 
 - (dispatch_queue_t)frameQueue {
   if (!_frameQueue) {
     _frameQueue =
-        dispatch_queue_create("org.webrtc.avfoundationvideocapturer.video",
-                              DISPATCH_QUEUE_SERIAL);
-    dispatch_set_target_queue(
-        _frameQueue,
-        dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0));
+        dispatch_queue_create("org.webrtc.avfoundationvideocapturer.video", DISPATCH_QUEUE_SERIAL);
+    dispatch_set_target_queue(_frameQueue,
+                              dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0));
   }
   return _frameQueue;
 }
@@ -309,7 +138,7 @@ static BOOL SetFormatForCaptureDevice(AVCaptureDevice *device,
   if (!self.canUseBackCamera) {
     if (useBackCamera) {
       RTCLogWarning(@"No rear-facing camera exists or it cannot be used;"
-                    "not switching.");
+                     "not switching.");
     }
     return;
   }
@@ -328,23 +157,24 @@ static BOOL SetFormatForCaptureDevice(AVCaptureDevice *device,
     return;
   }
   self.hasStarted = YES;
-  [RTCDispatcher dispatchAsyncOnType:RTCDispatcherTypeCaptureSession
-                               block:^{
+  [RTCDispatcher
+      dispatchAsyncOnType:RTCDispatcherTypeCaptureSession
+                    block:^{
 #if TARGET_OS_IPHONE
-     // Default to portrait orientation on iPhone. This will be reset in
-     // updateOrientation unless orientation is unknown/faceup/facedown.
-     _rotation = webrtc::kVideoRotation_90;
+                        // Default to portrait orientation on iPhone. This will be reset in
+                        // updateOrientation unless orientation is unknown/faceup/facedown.
+                        _rotation = webrtc::kVideoRotation_90;
 #else
-    // No rotation on Mac.
-    _rotation = webrtc::kVideoRotation_0;
+                        // No rotation on Mac.
+                        _rotation = webrtc::kVideoRotation_0;
 #endif
-    [self updateOrientation];
+                        [self updateOrientation];
 #if TARGET_OS_IPHONE
-    [[UIDevice currentDevice] beginGeneratingDeviceOrientationNotifications];
+                        [[UIDevice currentDevice] beginGeneratingDeviceOrientationNotifications];
 #endif
-    AVCaptureSession *captureSession = self.captureSession;
-    [captureSession startRunning];
-  }];
+                        AVCaptureSession *captureSession = self.captureSession;
+                        [captureSession startRunning];
+                    }];
 }
 
 // Called from same thread as start.
@@ -356,14 +186,15 @@ static BOOL SetFormatForCaptureDevice(AVCaptureDevice *device,
   // Due to this async block, it's possible that the ObjC object outlives the
   // C++ one. In order to not invoke functions on the C++ object, we set
   // hasStarted immediately instead of dispatching it async.
-  [RTCDispatcher dispatchAsyncOnType:RTCDispatcherTypeCaptureSession
-                               block:^{
-    [_videoDataOutput setSampleBufferDelegate:nil queue:nullptr];
-    [_captureSession stopRunning];
+  [RTCDispatcher
+      dispatchAsyncOnType:RTCDispatcherTypeCaptureSession
+                    block:^{
+                        [_videoDataOutput setSampleBufferDelegate:nil queue:nullptr];
+                        [_captureSession stopRunning];
 #if TARGET_OS_IPHONE
-    [[UIDevice currentDevice] endGeneratingDeviceOrientationNotifications];
+                        [[UIDevice currentDevice] endGeneratingDeviceOrientationNotifications];
 #endif
-  }];
+                    }];
 }
 
 #pragma mark iOS notifications
@@ -372,8 +203,8 @@ static BOOL SetFormatForCaptureDevice(AVCaptureDevice *device,
 - (void)deviceOrientationDidChange:(NSNotification *)notification {
   [RTCDispatcher dispatchAsyncOnType:RTCDispatcherTypeCaptureSession
                                block:^{
-    [self updateOrientation];
-  }];
+                                   [self updateOrientation];
+                               }];
 }
 #endif
 
@@ -399,10 +230,9 @@ static BOOL SetFormatForCaptureDevice(AVCaptureDevice *device,
 
 - (void)handleCaptureSessionInterruption:(NSNotification *)notification {
   NSString *reasonString = nil;
-#if defined(__IPHONE_9_0) && defined(__IPHONE_OS_VERSION_MAX_ALLOWED) \
-    && __IPHONE_OS_VERSION_MAX_ALLOWED >= __IPHONE_9_0
-  NSNumber *reason =
-      notification.userInfo[AVCaptureSessionInterruptionReasonKey];
+#if defined(__IPHONE_9_0) && defined(__IPHONE_OS_VERSION_MAX_ALLOWED) && \
+    __IPHONE_OS_VERSION_MAX_ALLOWED >= __IPHONE_9_0
+  NSNumber *reason = notification.userInfo[AVCaptureSessionInterruptionReasonKey];
   if (reason) {
     switch (reason.intValue) {
       case AVCaptureSessionInterruptionReasonVideoDeviceNotAvailableInBackground:
@@ -430,22 +260,21 @@ static BOOL SetFormatForCaptureDevice(AVCaptureDevice *device,
 }
 
 - (void)handleCaptureSessionRuntimeError:(NSNotification *)notification {
-  NSError *error =
-      [notification.userInfo objectForKey:AVCaptureSessionErrorKey];
+  NSError *error = [notification.userInfo objectForKey:AVCaptureSessionErrorKey];
   RTCLogError(@"Capture session runtime error: %@", error);
 
   [RTCDispatcher dispatchAsyncOnType:RTCDispatcherTypeCaptureSession
                                block:^{
 #if TARGET_OS_IPHONE
-    if (error.code == AVErrorMediaServicesWereReset) {
-      [self handleNonFatalError];
-    } else {
-      [self handleFatalError];
-    }
+                                   if (error.code == AVErrorMediaServicesWereReset) {
+                                     [self handleNonFatalError];
+                                   } else {
+                                     [self handleFatalError];
+                                   }
 #else
-    [self handleFatalError];
+                                   [self handleFatalError];
 #endif
-  }];
+                               }];
 }
 
 - (void)handleCaptureSessionDidStartRunning:(NSNotification *)notification {
@@ -454,10 +283,10 @@ static BOOL SetFormatForCaptureDevice(AVCaptureDevice *device,
   self.isRunning = YES;
   [RTCDispatcher dispatchAsyncOnType:RTCDispatcherTypeCaptureSession
                                block:^{
-    // If we successfully restarted after an unknown error, allow future
-    // retries on fatal errors.
-    _hasRetriedOnFatalError = NO;
-  }];
+                                   // If we successfully restarted after an unknown error,
+                                   // allow future retries on fatal errors.
+                                   _hasRetriedOnFatalError = NO;
+                               }];
 }
 
 - (void)handleCaptureSessionDidStopRunning:(NSNotification *)notification {
@@ -466,26 +295,27 @@ static BOOL SetFormatForCaptureDevice(AVCaptureDevice *device,
 }
 
 - (void)handleFatalError {
-  [RTCDispatcher dispatchAsyncOnType:RTCDispatcherTypeCaptureSession
-                               block:^{
-    if (!_hasRetriedOnFatalError) {
-      RTCLogWarning(@"Attempting to recover from fatal capture error.");
-      [self handleNonFatalError];
-      _hasRetriedOnFatalError = YES;
-    } else {
-      RTCLogError(@"Previous fatal error recovery failed.");
-    }
-  }];
+  [RTCDispatcher
+      dispatchAsyncOnType:RTCDispatcherTypeCaptureSession
+                    block:^{
+                        if (!_hasRetriedOnFatalError) {
+                          RTCLogWarning(@"Attempting to recover from fatal capture error.");
+                          [self handleNonFatalError];
+                          _hasRetriedOnFatalError = YES;
+                        } else {
+                          RTCLogError(@"Previous fatal error recovery failed.");
+                        }
+                    }];
 }
 
 - (void)handleNonFatalError {
   [RTCDispatcher dispatchAsyncOnType:RTCDispatcherTypeCaptureSession
                                block:^{
-    if (self.hasStarted) {
-      RTCLog(@"Restarting capture session after error.");
-      [self.captureSession startRunning];
-    }
-  }];
+                                   if (self.hasStarted) {
+                                     RTCLog(@"Restarting capture session after error.");
+                                     [self.captureSession startRunning];
+                                   }
+                               }];
 }
 
 #if TARGET_OS_IPHONE
@@ -495,11 +325,11 @@ static BOOL SetFormatForCaptureDevice(AVCaptureDevice *device,
 - (void)handleApplicationDidBecomeActive:(NSNotification *)notification {
   [RTCDispatcher dispatchAsyncOnType:RTCDispatcherTypeCaptureSession
                                block:^{
-    if (self.hasStarted && !self.captureSession.isRunning) {
-      RTCLog(@"Restarting capture session on active.");
-      [self.captureSession startRunning];
-    }
-  }];
+                                   if (self.hasStarted && !self.captureSession.isRunning) {
+                                     RTCLog(@"Restarting capture session on active.");
+                                     [self.captureSession startRunning];
+                                   }
+                               }];
 }
 
 #endif  // TARGET_OS_IPHONE
@@ -534,8 +364,7 @@ static BOOL SetFormatForCaptureDevice(AVCaptureDevice *device,
     RTCLogError(@"Session does not support capture inputs.");
     return NO;
   }
-  AVCaptureDeviceInput *input = self.useBackCamera ?
-      backCameraInput : frontCameraInput;
+  AVCaptureDeviceInput *input = self.useBackCamera ? backCameraInput : frontCameraInput;
   [captureSession addInput:input];
 
   _captureSession = captureSession;
@@ -546,11 +375,11 @@ static BOOL SetFormatForCaptureDevice(AVCaptureDevice *device,
   if (!_videoDataOutput) {
     // Make the capturer output NV12. Ideally we want I420 but that's not
     // currently supported on iPhone / iPad.
-    AVCaptureVideoDataOutput *videoDataOutput =
-        [[AVCaptureVideoDataOutput alloc] init];
+    AVCaptureVideoDataOutput *videoDataOutput = [[AVCaptureVideoDataOutput alloc] init];
     videoDataOutput.videoSettings = @{
-      (NSString *)kCVPixelBufferPixelFormatTypeKey :
-        @(kCVPixelFormatType_420YpCbCr8BiPlanarFullRange)
+      (NSString *)
+      // TODO(denicija): Remove this color conversion and use the original capture format directly.
+      kCVPixelBufferPixelFormatTypeKey : @(kCVPixelFormatType_420YpCbCr8BiPlanarFullRange)
     };
     videoDataOutput.alwaysDiscardsLateVideoFrames = NO;
     [videoDataOutput setSampleBufferDelegate:self queue:self.frameQueue];
@@ -559,10 +388,8 @@ static BOOL SetFormatForCaptureDevice(AVCaptureDevice *device,
   return _videoDataOutput;
 }
 
-- (AVCaptureDevice *)videoCaptureDeviceForPosition:
-    (AVCaptureDevicePosition)position {
-  for (AVCaptureDevice *captureDevice in
-       [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo]) {
+- (AVCaptureDevice *)videoCaptureDeviceForPosition:(AVCaptureDevicePosition)position {
+  for (AVCaptureDevice *captureDevice in [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo]) {
     if (captureDevice.position == position) {
       return captureDevice;
     }
@@ -585,11 +412,9 @@ static BOOL SetFormatForCaptureDevice(AVCaptureDevice *device,
     }
     NSError *error = nil;
     AVCaptureDeviceInput *frontCameraInput =
-        [AVCaptureDeviceInput deviceInputWithDevice:frontCameraDevice
-                                              error:&error];
+        [AVCaptureDeviceInput deviceInputWithDevice:frontCameraDevice error:&error];
     if (!frontCameraInput) {
-      RTCLogError(@"Failed to create front camera input: %@",
-                  error.localizedDescription);
+      RTCLogError(@"Failed to create front camera input: %@", error.localizedDescription);
       return nil;
     }
     _frontCameraInput = frontCameraInput;
@@ -607,11 +432,9 @@ static BOOL SetFormatForCaptureDevice(AVCaptureDevice *device,
     }
     NSError *error = nil;
     AVCaptureDeviceInput *backCameraInput =
-        [AVCaptureDeviceInput deviceInputWithDevice:backCameraDevice
-                                              error:&error];
+        [AVCaptureDeviceInput deviceInputWithDevice:backCameraDevice error:&error];
     if (!backCameraInput) {
-      RTCLogError(@"Failed to create front camera input: %@",
-                  error.localizedDescription);
+      RTCLogError(@"Failed to create front camera input: %@", error.localizedDescription);
       return nil;
     }
     _backCameraInput = backCameraInput;
@@ -630,12 +453,12 @@ static BOOL SetFormatForCaptureDevice(AVCaptureDevice *device,
       _rotation = webrtc::kVideoRotation_270;
       break;
     case UIDeviceOrientationLandscapeLeft:
-      _rotation = _capturer->GetUseBackCamera() ? webrtc::kVideoRotation_0
-                                                : webrtc::kVideoRotation_180;
+      _rotation =
+          _capturer->GetUseBackCamera() ? webrtc::kVideoRotation_0 : webrtc::kVideoRotation_180;
       break;
     case UIDeviceOrientationLandscapeRight:
-      _rotation = _capturer->GetUseBackCamera() ? webrtc::kVideoRotation_180
-                                                : webrtc::kVideoRotation_0;
+      _rotation =
+          _capturer->GetUseBackCamera() ? webrtc::kVideoRotation_180 : webrtc::kVideoRotation_0;
       break;
     case UIDeviceOrientationFaceUp:
     case UIDeviceOrientationFaceDown:
@@ -650,181 +473,28 @@ static BOOL SetFormatForCaptureDevice(AVCaptureDevice *device,
 - (void)updateSessionInputForUseBackCamera:(BOOL)useBackCamera {
   [RTCDispatcher dispatchAsyncOnType:RTCDispatcherTypeCaptureSession
                                block:^{
-    [_captureSession beginConfiguration];
-    AVCaptureDeviceInput *oldInput = _backCameraInput;
-    AVCaptureDeviceInput *newInput = _frontCameraInput;
-    if (useBackCamera) {
-      oldInput = _frontCameraInput;
-      newInput = _backCameraInput;
-    }
-    if (oldInput) {
-      // Ok to remove this even if it's not attached. Will be no-op.
-      [_captureSession removeInput:oldInput];
-    }
-    if (newInput) {
-      [_captureSession addInput:newInput];
-    }
-    [self updateOrientation];
-    AVCaptureDevice *newDevice = newInput.device;
-    const cricket::VideoFormat *format = _capturer->GetCaptureFormat();
-    SetFormatForCaptureDevice(newDevice, _captureSession, *format);
-    [_captureSession commitConfiguration];
-  }];
+                                   [_captureSession beginConfiguration];
+                                   AVCaptureDeviceInput *oldInput = _backCameraInput;
+                                   AVCaptureDeviceInput *newInput = _frontCameraInput;
+                                   if (useBackCamera) {
+                                     oldInput = _frontCameraInput;
+                                     newInput = _backCameraInput;
+                                   }
+                                   if (oldInput) {
+                                     // Ok to remove this even if it's not attached. Will be no-op.
+                                     [_captureSession removeInput:oldInput];
+                                   }
+                                   if (newInput) {
+                                     [_captureSession addInput:newInput];
+                                   }
+                                   [self updateOrientation];
+                                   AVCaptureDevice *newDevice = newInput.device;
+                                   const cricket::VideoFormat *format =
+                                     _capturer->GetCaptureFormat();
+                                   webrtc::SetFormatForCaptureDevice(
+                                       newDevice, _captureSession, *format);
+                                   [_captureSession commitConfiguration];
+                               }];
 }
 
 @end
-
-namespace webrtc {
-
-enum AVFoundationVideoCapturerMessageType : uint32_t {
-  kMessageTypeFrame,
-};
-
-AVFoundationVideoCapturer::AVFoundationVideoCapturer() : _capturer(nil) {
-  _capturer =
-      [[RTCAVFoundationVideoCapturerInternal alloc] initWithCapturer:this];
-
-  std::set<cricket::VideoFormat> front_camera_video_formats =
-      GetSupportedVideoFormatsForDevice([_capturer frontCaptureDevice]);
-
-  std::set<cricket::VideoFormat> back_camera_video_formats =
-      GetSupportedVideoFormatsForDevice([_capturer backCaptureDevice]);
-
-  std::vector<cricket::VideoFormat> intersection_video_formats;
-  if (back_camera_video_formats.empty()) {
-    intersection_video_formats.assign(front_camera_video_formats.begin(),
-                                      front_camera_video_formats.end());
-
-  } else if (front_camera_video_formats.empty()) {
-    intersection_video_formats.assign(back_camera_video_formats.begin(),
-                                      back_camera_video_formats.end());
-  } else {
-    std::set_intersection(
-        front_camera_video_formats.begin(), front_camera_video_formats.end(),
-        back_camera_video_formats.begin(), back_camera_video_formats.end(),
-        std::back_inserter(intersection_video_formats));
-  }
-  SetSupportedFormats(intersection_video_formats);
-}
-
-AVFoundationVideoCapturer::~AVFoundationVideoCapturer() {
-  _capturer = nil;
-}
-
-cricket::CaptureState AVFoundationVideoCapturer::Start(
-    const cricket::VideoFormat& format) {
-  if (!_capturer) {
-    LOG(LS_ERROR) << "Failed to create AVFoundation capturer.";
-    return cricket::CaptureState::CS_FAILED;
-  }
-  if (_capturer.isRunning) {
-    LOG(LS_ERROR) << "The capturer is already running.";
-    return cricket::CaptureState::CS_FAILED;
-  }
-
-  AVCaptureDevice* device = [_capturer getActiveCaptureDevice];
-  AVCaptureSession* session = _capturer.captureSession;
-
-  if (!SetFormatForCaptureDevice(device, session, format)) {
-    return cricket::CaptureState::CS_FAILED;
-  }
-
-  SetCaptureFormat(&format);
-  // This isn't super accurate because it takes a while for the AVCaptureSession
-  // to spin up, and this call returns async.
-  // TODO(tkchin): make this better.
-  [_capturer start];
-  SetCaptureState(cricket::CaptureState::CS_RUNNING);
-
-  return cricket::CaptureState::CS_STARTING;
-}
-
-void AVFoundationVideoCapturer::Stop() {
-  [_capturer stop];
-  SetCaptureFormat(NULL);
-}
-
-bool AVFoundationVideoCapturer::IsRunning() {
-  return _capturer.isRunning;
-}
-
-AVCaptureSession* AVFoundationVideoCapturer::GetCaptureSession() {
-  return _capturer.captureSession;
-}
-
-bool AVFoundationVideoCapturer::CanUseBackCamera() const {
-  return _capturer.canUseBackCamera;
-}
-
-void AVFoundationVideoCapturer::SetUseBackCamera(bool useBackCamera) {
-  _capturer.useBackCamera = useBackCamera;
-}
-
-bool AVFoundationVideoCapturer::GetUseBackCamera() const {
-  return _capturer.useBackCamera;
-}
-
-void AVFoundationVideoCapturer::CaptureSampleBuffer(
-    CMSampleBufferRef sample_buffer, VideoRotation rotation) {
-  if (CMSampleBufferGetNumSamples(sample_buffer) != 1 ||
-      !CMSampleBufferIsValid(sample_buffer) ||
-      !CMSampleBufferDataIsReady(sample_buffer)) {
-    return;
-  }
-
-  CVImageBufferRef image_buffer = CMSampleBufferGetImageBuffer(sample_buffer);
-  if (image_buffer == NULL) {
-    return;
-  }
-
-  const int captured_width = CVPixelBufferGetWidth(image_buffer);
-  const int captured_height = CVPixelBufferGetHeight(image_buffer);
-
-  int adapted_width;
-  int adapted_height;
-  int crop_width;
-  int crop_height;
-  int crop_x;
-  int crop_y;
-  int64_t translated_camera_time_us;
-
-  if (!AdaptFrame(captured_width, captured_height,
-                  rtc::TimeNanos() / rtc::kNumNanosecsPerMicrosec,
-                  rtc::TimeMicros(), &adapted_width, &adapted_height,
-                  &crop_width, &crop_height, &crop_x, &crop_y,
-                  &translated_camera_time_us)) {
-    return;
-  }
-
-  rtc::scoped_refptr<VideoFrameBuffer> buffer =
-      new rtc::RefCountedObject<CoreVideoFrameBuffer>(
-          image_buffer,
-          adapted_width, adapted_height,
-          crop_width, crop_height,
-          crop_x, crop_y);
-
-  // Applying rotation is only supported for legacy reasons and performance is
-  // not critical here.
-  if (apply_rotation() && rotation != kVideoRotation_0) {
-    buffer = buffer->NativeToI420Buffer();
-    rtc::scoped_refptr<I420Buffer> rotated_buffer =
-        (rotation == kVideoRotation_180)
-            ? I420Buffer::Create(adapted_width, adapted_height)
-            : I420Buffer::Create(adapted_height, adapted_width);
-    libyuv::I420Rotate(
-        buffer->DataY(), buffer->StrideY(),
-        buffer->DataU(), buffer->StrideU(),
-        buffer->DataV(), buffer->StrideV(),
-        rotated_buffer->MutableDataY(), rotated_buffer->StrideY(),
-        rotated_buffer->MutableDataU(), rotated_buffer->StrideU(),
-        rotated_buffer->MutableDataV(), rotated_buffer->StrideV(),
-        buffer->width(), buffer->height(),
-        static_cast<libyuv::RotationMode>(rotation));
-    buffer = rotated_buffer;
-  }
-
-  OnFrame(webrtc::VideoFrame(buffer, rotation, translated_camera_time_us),
-          captured_width, captured_height);
-}
-
-}  // namespace webrtc