Split avfoundationcapturer classes in separate files.

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

 /*
- *  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
  *  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.
  */
 
-#include "avfoundationvideocapturer.h"
+#import "RTCAVFoundationFormatMapper.h"
 
-#import <AVFoundation/AVFoundation.h>
-#import <Foundation/Foundation.h>
-#if TARGET_OS_IPHONE
-#import <UIKit/UIKit.h>
-#endif
-
-#import "RTCDispatcher+Private.h"
+//#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];
+@implementation RTCAVFoundationFormatMapper
+
++ (NSArray<AVCaptureDeviceFormat *> *)eligibleFormatsForDevice:(const AVCaptureDevice *)device
+                                                  supportedFps:(int)fps {
+  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);
+    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)) {
+      if (IsFrameRateWithinRange(fps, 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 *)formatForDevice:(AVCaptureDevice *)device
+                               videoFormat:(const cricket::VideoFormat &)videoFormat {
   AVCaptureDeviceFormat *desiredDeviceFormat = nil;
   NSArray<AVCaptureDeviceFormat *> *eligibleFormats =
-      GetEligibleDeviceFormats(device, videoFormat.framerate());
+      [RTCAVFoundationFormatMapper eligibleFormatsForDevice:device
+                                               supportedFps:videoFormat.framerate()];
 
   for (AVCaptureDeviceFormat *deviceFormat in eligibleFormats) {
     CMVideoDimensions dimension =
         CMVideoFormatDescriptionGetDimensions(deviceFormat.formatDescription);
-    FourCharCode mediaSubType =
-        CMFormatDescriptionGetMediaSubType(deviceFormat.formatDescription);
+    FourCharCode mediaSubType = CMFormatDescriptionGetMediaSubType(deviceFormat.formatDescription);
 
-    if (videoFormat.width == dimension.width &&
-        videoFormat.height == dimension.height) {
+    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>)supportedVideoFormatsForDevice:(AVCaptureDevice *)device {
   std::set<cricket::VideoFormat> supportedFormats;
 
   NSArray<AVCaptureDeviceFormat *> *eligibleFormats =
-      GetEligibleDeviceFormats(device, kFramesPerSecond);
+      [RTCAVFoundationFormatMapper eligibleFormatsForDevice:device supportedFps:kFramesPerSecond];
 
   for (AVCaptureDeviceFormat *deviceFormat in eligibleFormats) {
     CMVideoDimensions dimension =
         CMVideoFormatDescriptionGetDimensions(deviceFormat.formatDescription);
     cricket::VideoFormat format = cricket::VideoFormat(
-        dimension.width, dimension.height,
-        cricket::VideoFormat::FpsToInterval(kFramesPerSecond),
+        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) {
++ (BOOL)setFormat:(const cricket::VideoFormat)format
+ forCaptureDevice:(AVCaptureDevice *)device
+   captureSession:(AVCaptureSession *)session {
   AVCaptureDeviceFormat *deviceFormat =
-      GetDeviceFormatForVideoFormat(device, format);
+      [RTCAVFoundationFormatMapper formatForDevice:device videoFormat: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);
+      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);
+    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
-
-@implementation RTCAVFoundationVideoCapturerInternal {
-  // Keep pointers to inputs for convenience.
-  AVCaptureDeviceInput *_frontCameraInput;
-  AVCaptureDeviceInput *_backCameraInput;
-  AVCaptureVideoDataOutput *_videoDataOutput;
-  // The cricket::VideoCapturer that owns this class. Should never be NULL.
-  webrtc::AVFoundationVideoCapturer *_capturer;
-  webrtc::VideoRotation _rotation;
-  BOOL _hasRetriedOnFatalError;
-  BOOL _isRunning;
-  BOOL _hasStarted;
-  rtc::CriticalSection _crit;
-}
-
-@synthesize captureSession = _captureSession;
-@synthesize frameQueue = _frameQueue;
-@synthesize useBackCamera = _useBackCamera;
-
-@synthesize isRunning = _isRunning;
-@synthesize hasStarted = _hasStarted;
-
-// This is called from the thread that creates the video source, which is likely
-// the main thread.
-- (instancetype)initWithCapturer:(webrtc::AVFoundationVideoCapturer *)capturer {
-  RTC_DCHECK(capturer);
-  if (self = [super init]) {
-    _capturer = capturer;
-    // Create the capture session and all relevant inputs and outputs. We need
-    // to do this in init because the application may want the capture session
-    // before we start the capturer for e.g. AVCapturePreviewLayer. All objects
-    // created here are retained until dealloc and never recreated.
-    if (![self setupCaptureSession]) {
-      return nil;
-    }
-    NSNotificationCenter *center = [NSNotificationCenter defaultCenter];
-#if TARGET_OS_IPHONE
-    [center addObserver:self
-               selector:@selector(deviceOrientationDidChange:)
-                   name:UIDeviceOrientationDidChangeNotification
-                 object:nil];
-    [center addObserver:self
-               selector:@selector(handleCaptureSessionInterruption:)
-                   name:AVCaptureSessionWasInterruptedNotification
-                 object:_captureSession];
-    [center addObserver:self
-               selector:@selector(handleCaptureSessionInterruptionEnded:)
-                   name:AVCaptureSessionInterruptionEndedNotification
-                 object:_captureSession];
-    [center addObserver:self
-               selector:@selector(handleApplicationDidBecomeActive:)
-                   name:UIApplicationDidBecomeActiveNotification
-                 object:[UIApplication sharedApplication]];
-#endif
-    [center addObserver:self
-               selector:@selector(handleCaptureSessionRuntimeError:)
-                   name:AVCaptureSessionRuntimeErrorNotification
-                 object:_captureSession];
-    [center addObserver:self
-               selector:@selector(handleCaptureSessionDidStartRunning:)
-                   name:AVCaptureSessionDidStartRunningNotification
-                 object:_captureSession];
-    [center addObserver:self
-               selector:@selector(handleCaptureSessionDidStopRunning:)
-                   name:AVCaptureSessionDidStopRunningNotification
-                 object:_captureSession];
-  }
-  return self;
-}
-
-- (void)dealloc {
-  RTC_DCHECK(!self.hasStarted);
-  [[NSNotificationCenter defaultCenter] removeObserver:self];
-  _capturer = nullptr;
-}
-
-- (AVCaptureSession *)captureSession {
-  return _captureSession;
-}
-
-- (AVCaptureDevice *)getActiveCaptureDevice {
-  return self.useBackCamera ? _backCameraInput.device : _frontCameraInput.device;
-}
-
-- (AVCaptureDevice *)frontCaptureDevice {
-  return _frontCameraInput.device;
-}
-
-- (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));
-  }
-  return _frameQueue;
-}
-
-// Called from any thread (likely main thread).
-- (BOOL)canUseBackCamera {
-  return _backCameraInput != nil;
-}
-
-// Called from any thread (likely main thread).
-- (BOOL)useBackCamera {
-  @synchronized(self) {
-    return _useBackCamera;
-  }
-}
-
-// Called from any thread (likely main thread).
-- (void)setUseBackCamera:(BOOL)useBackCamera {
-  if (!self.canUseBackCamera) {
-    if (useBackCamera) {
-      RTCLogWarning(@"No rear-facing camera exists or it cannot be used;"
-                    "not switching.");
-    }
-    return;
-  }
-  @synchronized(self) {
-    if (_useBackCamera == useBackCamera) {
-      return;
-    }
-    _useBackCamera = useBackCamera;
-    [self updateSessionInputForUseBackCamera:useBackCamera];
-  }
-}
-
-// Called from WebRTC thread.
-- (void)start {
-  if (self.hasStarted) {
-    return;
-  }
-  self.hasStarted = YES;
-  [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;
-#else
-    // No rotation on Mac.
-    _rotation = webrtc::kVideoRotation_0;
-#endif
-    [self updateOrientation];
-#if TARGET_OS_IPHONE
-    [[UIDevice currentDevice] beginGeneratingDeviceOrientationNotifications];
-#endif
-    AVCaptureSession *captureSession = self.captureSession;
-    [captureSession startRunning];
-  }];
-}
-
-// Called from same thread as start.
-- (void)stop {
-  if (!self.hasStarted) {
-    return;
-  }
-  self.hasStarted = NO;
-  // 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];
-#if TARGET_OS_IPHONE
-    [[UIDevice currentDevice] endGeneratingDeviceOrientationNotifications];
-#endif
-  }];
-}
-
-#pragma mark iOS notifications
-
-#if TARGET_OS_IPHONE
-- (void)deviceOrientationDidChange:(NSNotification *)notification {
-  [RTCDispatcher dispatchAsyncOnType:RTCDispatcherTypeCaptureSession
-                               block:^{
-    [self updateOrientation];
-  }];
-}
-#endif
-
-#pragma mark AVCaptureVideoDataOutputSampleBufferDelegate
-
-- (void)captureOutput:(AVCaptureOutput *)captureOutput
-    didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer
-           fromConnection:(AVCaptureConnection *)connection {
-  NSParameterAssert(captureOutput == _videoDataOutput);
-  if (!self.hasStarted) {
-    return;
-  }
-  _capturer->CaptureSampleBuffer(sampleBuffer, _rotation);
-}
-
-- (void)captureOutput:(AVCaptureOutput *)captureOutput
-    didDropSampleBuffer:(CMSampleBufferRef)sampleBuffer
-         fromConnection:(AVCaptureConnection *)connection {
-  RTCLogError(@"Dropped sample buffer.");
-}
-
-#pragma mark - AVCaptureSession notifications
-
-- (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 (reason) {
-    switch (reason.intValue) {
-      case AVCaptureSessionInterruptionReasonVideoDeviceNotAvailableInBackground:
-        reasonString = @"VideoDeviceNotAvailableInBackground";
-        break;
-      case AVCaptureSessionInterruptionReasonAudioDeviceInUseByAnotherClient:
-        reasonString = @"AudioDeviceInUseByAnotherClient";
-        break;
-      case AVCaptureSessionInterruptionReasonVideoDeviceInUseByAnotherClient:
-        reasonString = @"VideoDeviceInUseByAnotherClient";
-        break;
-      case AVCaptureSessionInterruptionReasonVideoDeviceNotAvailableWithMultipleForegroundApps:
-        reasonString = @"VideoDeviceNotAvailableWithMultipleForegroundApps";
-        break;
-    }
-  }
-#endif
-  RTCLog(@"Capture session interrupted: %@", reasonString);
-  // TODO(tkchin): Handle this case.
-}
-
-- (void)handleCaptureSessionInterruptionEnded:(NSNotification *)notification {
-  RTCLog(@"Capture session interruption ended.");
-  // TODO(tkchin): Handle this case.
-}
-
-- (void)handleCaptureSessionRuntimeError:(NSNotification *)notification {
-  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];
-    }
-#else
-    [self handleFatalError];
-#endif
-  }];
-}
-
-- (void)handleCaptureSessionDidStartRunning:(NSNotification *)notification {
-  RTCLog(@"Capture session started.");
-
-  self.isRunning = YES;
-  [RTCDispatcher dispatchAsyncOnType:RTCDispatcherTypeCaptureSession
-                               block:^{
-    // If we successfully restarted after an unknown error, allow future
-    // retries on fatal errors.
-    _hasRetriedOnFatalError = NO;
-  }];
-}
-
-- (void)handleCaptureSessionDidStopRunning:(NSNotification *)notification {
-  RTCLog(@"Capture session stopped.");
-  self.isRunning = NO;
-}
-
-- (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.");
-    }
-  }];
-}
-
-- (void)handleNonFatalError {
-  [RTCDispatcher dispatchAsyncOnType:RTCDispatcherTypeCaptureSession
-                               block:^{
-    if (self.hasStarted) {
-      RTCLog(@"Restarting capture session after error.");
-      [self.captureSession startRunning];
-    }
-  }];
-}
-
-#if TARGET_OS_IPHONE
-
-#pragma mark - UIApplication notifications
-
-- (void)handleApplicationDidBecomeActive:(NSNotification *)notification {
-  [RTCDispatcher dispatchAsyncOnType:RTCDispatcherTypeCaptureSession
-                               block:^{
-    if (self.hasStarted && !self.captureSession.isRunning) {
-      RTCLog(@"Restarting capture session on active.");
-      [self.captureSession startRunning];
-    }
-  }];
-}
-
-#endif  // TARGET_OS_IPHONE
-
-#pragma mark - Private
-
-- (BOOL)setupCaptureSession {
-  AVCaptureSession *captureSession = [[AVCaptureSession alloc] init];
-#if defined(WEBRTC_IOS)
-  captureSession.usesApplicationAudioSession = NO;
-#endif
-  // Add the output.
-  AVCaptureVideoDataOutput *videoDataOutput = [self videoDataOutput];
-  if (![captureSession canAddOutput:videoDataOutput]) {
-    RTCLogError(@"Video data output unsupported.");
-    return NO;
-  }
-  [captureSession addOutput:videoDataOutput];
-
-  // Get the front and back cameras. If there isn't a front camera
-  // give up.
-  AVCaptureDeviceInput *frontCameraInput = [self frontCameraInput];
-  AVCaptureDeviceInput *backCameraInput = [self backCameraInput];
-  if (!frontCameraInput) {
-    RTCLogError(@"No front camera for capture session.");
-    return NO;
-  }
-
-  // Add the inputs.
-  if (![captureSession canAddInput:frontCameraInput] ||
-      (backCameraInput && ![captureSession canAddInput:backCameraInput])) {
-    RTCLogError(@"Session does not support capture inputs.");
-    return NO;
-  }
-  AVCaptureDeviceInput *input = self.useBackCamera ?
-      backCameraInput : frontCameraInput;
-  [captureSession addInput:input];
-
-  _captureSession = captureSession;
-  return YES;
-}
-
-- (AVCaptureVideoDataOutput *)videoDataOutput {
-  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];
-    videoDataOutput.videoSettings = @{
-      (NSString *)kCVPixelBufferPixelFormatTypeKey :
-        @(kCVPixelFormatType_420YpCbCr8BiPlanarFullRange)
-    };
-    videoDataOutput.alwaysDiscardsLateVideoFrames = NO;
-    [videoDataOutput setSampleBufferDelegate:self queue:self.frameQueue];
-    _videoDataOutput = videoDataOutput;
-  }
-  return _videoDataOutput;
-}
-
-- (AVCaptureDevice *)videoCaptureDeviceForPosition:
-    (AVCaptureDevicePosition)position {
-  for (AVCaptureDevice *captureDevice in
-       [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo]) {
-    if (captureDevice.position == position) {
-      return captureDevice;
-    }
-  }
-  return nil;
-}
-
-- (AVCaptureDeviceInput *)frontCameraInput {
-  if (!_frontCameraInput) {
-#if TARGET_OS_IPHONE
-    AVCaptureDevice *frontCameraDevice =
-        [self videoCaptureDeviceForPosition:AVCaptureDevicePositionFront];
-#else
-    AVCaptureDevice *frontCameraDevice =
-        [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
-#endif
-    if (!frontCameraDevice) {
-      RTCLogWarning(@"Failed to find front capture device.");
-      return nil;
-    }
-    NSError *error = nil;
-    AVCaptureDeviceInput *frontCameraInput =
-        [AVCaptureDeviceInput deviceInputWithDevice:frontCameraDevice
-                                              error:&error];
-    if (!frontCameraInput) {
-      RTCLogError(@"Failed to create front camera input: %@",
-                  error.localizedDescription);
-      return nil;
-    }
-    _frontCameraInput = frontCameraInput;
-  }
-  return _frontCameraInput;
-}
-
-- (AVCaptureDeviceInput *)backCameraInput {
-  if (!_backCameraInput) {
-    AVCaptureDevice *backCameraDevice =
-        [self videoCaptureDeviceForPosition:AVCaptureDevicePositionBack];
-    if (!backCameraDevice) {
-      RTCLogWarning(@"Failed to find front capture device.");
-      return nil;
-    }
-    NSError *error = nil;
-    AVCaptureDeviceInput *backCameraInput =
-        [AVCaptureDeviceInput deviceInputWithDevice:backCameraDevice
-                                              error:&error];
-    if (!backCameraInput) {
-      RTCLogError(@"Failed to create front camera input: %@",
-                  error.localizedDescription);
-      return nil;
-    }
-    _backCameraInput = backCameraInput;
-  }
-  return _backCameraInput;
-}
-
-// Called from capture session queue.
-- (void)updateOrientation {
-#if TARGET_OS_IPHONE
-  switch ([UIDevice currentDevice].orientation) {
-    case UIDeviceOrientationPortrait:
-      _rotation = webrtc::kVideoRotation_90;
-      break;
-    case UIDeviceOrientationPortraitUpsideDown:
-      _rotation = webrtc::kVideoRotation_270;
-      break;
-    case UIDeviceOrientationLandscapeLeft:
-      _rotation = _capturer->GetUseBackCamera() ? webrtc::kVideoRotation_0
-                                                : webrtc::kVideoRotation_180;
-      break;
-    case UIDeviceOrientationLandscapeRight:
-      _rotation = _capturer->GetUseBackCamera() ? webrtc::kVideoRotation_180
-                                                : webrtc::kVideoRotation_0;
-      break;
-    case UIDeviceOrientationFaceUp:
-    case UIDeviceOrientationFaceDown:
-    case UIDeviceOrientationUnknown:
-      // Ignore.
-      break;
-  }
-#endif
-}
-
-// Update the current session input to match what's stored in _useBackCamera.
-- (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];
-  }];
-}
-
-@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