Moving src/webrtc into src/.

In order to eliminate the WebRTC Subtree mirror in Chromium, 
WebRTC is moving the content of the src/webrtc directory up
to the src/ directory.

NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
TBR=tommi@webrtc.org

Bug: chromium:611808
Change-Id: Iac59c5b51b950f174119565bac87955a7994bc38
Reviewed-on: https://webrtc-review.googlesource.com/1560
Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org>
Reviewed-by: Henrik Kjellander <kjellander@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#19845}

sdk/objc/Framework/Classes/Video/AVCaptureSession+DevicePosition.h

@@ -0,0 +1,23 @@
+/*
+ *  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 <AVFoundation/AVFoundation.h>
+#import <CoreMedia/CoreMedia.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+@interface AVCaptureSession (DevicePosition)
+
+// Check the image's EXIF for the camera the image came from.
++ (AVCaptureDevicePosition)devicePositionForSampleBuffer:(CMSampleBufferRef)sampleBuffer;
+
+@end
+
+NS_ASSUME_NONNULL_END

sdk/objc/Framework/Classes/Video/AVCaptureSession+DevicePosition.mm

@@ -0,0 +1,51 @@
+/*
+ *  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 "AVCaptureSession+DevicePosition.h"
+
+BOOL CFStringContainsString(CFStringRef theString, CFStringRef stringToFind) {
+  return CFStringFindWithOptions(theString,
+                                 stringToFind,
+                                 CFRangeMake(0, CFStringGetLength(theString)),
+                                 kCFCompareCaseInsensitive,
+                                 nil);
+}
+
+@implementation AVCaptureSession (DevicePosition)
+
++ (AVCaptureDevicePosition)devicePositionForSampleBuffer:(CMSampleBufferRef)sampleBuffer {
+  // Check the image's EXIF for the camera the image came from.
+  AVCaptureDevicePosition cameraPosition = AVCaptureDevicePositionUnspecified;
+  CFDictionaryRef attachments = CMCopyDictionaryOfAttachments(
+      kCFAllocatorDefault, sampleBuffer, kCMAttachmentMode_ShouldPropagate);
+  if (attachments) {
+    int size = CFDictionaryGetCount(attachments);
+    if (size > 0) {
+      CFDictionaryRef cfExifDictVal = nil;
+      if (CFDictionaryGetValueIfPresent(
+              attachments, (const void *)CFSTR("{Exif}"), (const void **)&cfExifDictVal)) {
+        CFStringRef cfLensModelStrVal;
+        if (CFDictionaryGetValueIfPresent(cfExifDictVal,
+                                          (const void *)CFSTR("LensModel"),
+                                          (const void **)&cfLensModelStrVal)) {
+          if (CFStringContainsString(cfLensModelStrVal, CFSTR("front"))) {
+            cameraPosition = AVCaptureDevicePositionFront;
+          } else if (CFStringContainsString(cfLensModelStrVal, CFSTR("back"))) {
+            cameraPosition = AVCaptureDevicePositionBack;
+          }
+        }
+      }
+    }
+    CFRelease(attachments);
+  }
+  return cameraPosition;
+}
+
+@end

sdk/objc/Framework/Classes/Video/RTCAVFoundationVideoCapturerInternal.h

@@ -0,0 +1,49 @@
+/*
+ *  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.
+ */
+
+#import <AVFoundation/AVFoundation.h>
+#import <Foundation/Foundation.h>
+
+#ifdef __cplusplus
+#include "avfoundationvideocapturer.h"
+#endif
+
+NS_ASSUME_NONNULL_BEGIN
+// This class is an implementation detail of AVFoundationVideoCapturer and handles
+// the ObjC integration with the AVFoundation APIs.
+// It is meant to be owned by an instance of AVFoundationVideoCapturer.
+// The reason for this is 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
+NS_ASSUME_NONNULL_END

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

@@ -0,0 +1,518 @@
+/*
+ *  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.
+ */
+
+#import "RTCAVFoundationVideoCapturerInternal.h"
+
+#import <Foundation/Foundation.h>
+#if TARGET_OS_IPHONE
+#import <UIKit/UIKit.h>
+#import "WebRTC/UIDevice+RTCDevice.h"
+#endif
+
+#import "AVCaptureSession+DevicePosition.h"
+#import "RTCDispatcher+Private.h"
+#import "WebRTC/RTCLogging.h"
+
+#include "avfoundationformatmapper.h"
+
+@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;
+  BOOL _hasRetriedOnFatalError;
+  BOOL _isRunning;
+  BOOL _hasStarted;
+  rtc::CriticalSection _crit;
+#if TARGET_OS_IPHONE
+  UIDeviceOrientation _orientation;
+#endif
+}
+
+@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
+    _orientation = UIDeviceOrientationPortrait;
+    [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;
+}
+
+- (nullable AVCaptureDevice *)frontCaptureDevice {
+  return _frontCameraInput.device;
+}
+
+- (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));
+  }
+  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:^{
+                        [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;
+  }
+
+#if TARGET_OS_IPHONE
+  // Default to portrait orientation on iPhone.
+  webrtc::VideoRotation rotation = webrtc::kVideoRotation_90;
+  BOOL usingFrontCamera = NO;
+  // Check the image's EXIF for the camera the image came from as the image could have been
+  // delayed as we set alwaysDiscardsLateVideoFrames to NO.
+  AVCaptureDevicePosition cameraPosition =
+      [AVCaptureSession devicePositionForSampleBuffer:sampleBuffer];
+  if (cameraPosition != AVCaptureDevicePositionUnspecified) {
+    usingFrontCamera = AVCaptureDevicePositionFront == cameraPosition;
+  } else {
+    AVCaptureDeviceInput *deviceInput =
+        (AVCaptureDeviceInput *)((AVCaptureInputPort *)connection.inputPorts.firstObject).input;
+    usingFrontCamera = AVCaptureDevicePositionFront == deviceInput.device.position;
+  }
+  switch (_orientation) {
+    case UIDeviceOrientationPortrait:
+      rotation = webrtc::kVideoRotation_90;
+      break;
+    case UIDeviceOrientationPortraitUpsideDown:
+      rotation = webrtc::kVideoRotation_270;
+      break;
+    case UIDeviceOrientationLandscapeLeft:
+      rotation = usingFrontCamera ? webrtc::kVideoRotation_180 : webrtc::kVideoRotation_0;
+      break;
+    case UIDeviceOrientationLandscapeRight:
+      rotation = usingFrontCamera ? webrtc::kVideoRotation_0 : webrtc::kVideoRotation_180;
+      break;
+    case UIDeviceOrientationFaceUp:
+    case UIDeviceOrientationFaceDown:
+    case UIDeviceOrientationUnknown:
+      // Ignore.
+      break;
+  }
+#else
+  // No rotation on Mac.
+  webrtc::VideoRotation rotation = webrtc::kVideoRotation_0;
+#endif
+
+  _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
+  if ([UIDevice isIOS9OrLater]) {
+    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 *)
+      // 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];
+    _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
+  _orientation = [UIDevice currentDevice].orientation;
+#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();
+                      webrtc::SetFormatForCaptureDevice(newDevice, _captureSession, *format);
+                      [_captureSession commitConfiguration];
+                    }];
+}
+
+@end

sdk/objc/Framework/Classes/Video/RTCCVPixelBuffer.mm

@@ -0,0 +1,188 @@
+/*
+ *  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 "WebRTC/RTCVideoFrameBuffer.h"
+
+#include "webrtc/common_video/libyuv/include/webrtc_libyuv.h"
+#include "webrtc/rtc_base/checks.h"
+#include "webrtc/rtc_base/logging.h"
+
+@implementation RTCCVPixelBuffer {
+  int _width;
+  int _height;
+  int _bufferWidth;
+  int _bufferHeight;
+  int _cropWidth;
+  int _cropHeight;
+}
+
+@synthesize pixelBuffer = _pixelBuffer;
+@synthesize cropX = _cropX;
+@synthesize cropY = _cropY;
+
+- (instancetype)initWithPixelBuffer:(CVPixelBufferRef)pixelBuffer {
+  return [self initWithPixelBuffer:pixelBuffer
+                      adaptedWidth:CVPixelBufferGetWidth(pixelBuffer)
+                     adaptedHeight:CVPixelBufferGetHeight(pixelBuffer)
+                         cropWidth:CVPixelBufferGetWidth(pixelBuffer)
+                        cropHeight:CVPixelBufferGetHeight(pixelBuffer)
+                             cropX:0
+                             cropY:0];
+}
+
+- (instancetype)initWithPixelBuffer:(CVPixelBufferRef)pixelBuffer
+                       adaptedWidth:(int)adaptedWidth
+                      adaptedHeight:(int)adaptedHeight
+                          cropWidth:(int)cropWidth
+                         cropHeight:(int)cropHeight
+                              cropX:(int)cropX
+                              cropY:(int)cropY {
+  if (self = [super init]) {
+    _width = adaptedWidth;
+    _height = adaptedHeight;
+    _pixelBuffer = pixelBuffer;
+    _bufferWidth = CVPixelBufferGetWidth(_pixelBuffer);
+    _bufferHeight = CVPixelBufferGetHeight(_pixelBuffer);
+    _cropWidth = cropWidth;
+    _cropHeight = cropHeight;
+    // Can only crop at even pixels.
+    _cropX = cropX & ~1;
+    _cropY = cropY & ~1;
+    CVBufferRetain(_pixelBuffer);
+  }
+
+  return self;
+}
+
+- (void)dealloc {
+  CVBufferRelease(_pixelBuffer);
+}
+
+- (int)width {
+  return _width;
+}
+
+- (int)height {
+  return _height;
+}
+
+- (BOOL)requiresCropping {
+  return _cropWidth != _bufferWidth || _cropHeight != _bufferHeight;
+}
+
+- (BOOL)requiresScalingToWidth:(int)width height:(int)height {
+  return _cropWidth != width || _cropHeight != height;
+}
+
+- (int)bufferSizeForCroppingAndScalingToWidth:(int)width height:(int)height {
+  int srcChromaWidth = (_cropWidth + 1) / 2;
+  int srcChromaHeight = (_cropHeight + 1) / 2;
+  int dstChromaWidth = (width + 1) / 2;
+  int dstChromaHeight = (height + 1) / 2;
+
+  return srcChromaWidth * srcChromaHeight * 2 + dstChromaWidth * dstChromaHeight * 2;
+}
+
+- (BOOL)cropAndScaleTo:(CVPixelBufferRef)outputPixelBuffer withTempBuffer:(uint8_t*)tmpBuffer {
+  // Prepare output pointers.
+  RTC_DCHECK_EQ(CVPixelBufferGetPixelFormatType(outputPixelBuffer),
+                kCVPixelFormatType_420YpCbCr8BiPlanarFullRange);
+  CVReturn cvRet = CVPixelBufferLockBaseAddress(outputPixelBuffer, 0);
+  if (cvRet != kCVReturnSuccess) {
+    LOG(LS_ERROR) << "Failed to lock base address: " << cvRet;
+    return NO;
+  }
+  const int dstWidth = CVPixelBufferGetWidth(outputPixelBuffer);
+  const int dstHeight = CVPixelBufferGetHeight(outputPixelBuffer);
+  uint8_t* dstY =
+      reinterpret_cast<uint8_t*>(CVPixelBufferGetBaseAddressOfPlane(outputPixelBuffer, 0));
+  const int dstYStride = CVPixelBufferGetBytesPerRowOfPlane(outputPixelBuffer, 0);
+  uint8_t* dstUV =
+      reinterpret_cast<uint8_t*>(CVPixelBufferGetBaseAddressOfPlane(outputPixelBuffer, 1));
+  const int dstUVStride = CVPixelBufferGetBytesPerRowOfPlane(outputPixelBuffer, 1);
+
+  // Prepare source pointers.
+  const OSType srcPixelFormat = CVPixelBufferGetPixelFormatType(_pixelBuffer);
+  RTC_DCHECK(srcPixelFormat == kCVPixelFormatType_420YpCbCr8BiPlanarFullRange ||
+             srcPixelFormat == kCVPixelFormatType_420YpCbCr8BiPlanarVideoRange);
+  CVPixelBufferLockBaseAddress(_pixelBuffer, kCVPixelBufferLock_ReadOnly);
+  const uint8_t* srcY =
+      static_cast<const uint8_t*>(CVPixelBufferGetBaseAddressOfPlane(_pixelBuffer, 0));
+  const int srcYStride = CVPixelBufferGetBytesPerRowOfPlane(_pixelBuffer, 0);
+  const uint8_t* srcUV =
+      static_cast<const uint8_t*>(CVPixelBufferGetBaseAddressOfPlane(_pixelBuffer, 1));
+  const int srcUVStride = CVPixelBufferGetBytesPerRowOfPlane(_pixelBuffer, 1);
+
+  // Crop just by modifying pointers.
+  srcY += srcYStride * _cropY + _cropX;
+  srcUV += srcUVStride * (_cropY / 2) + _cropX;
+
+  webrtc::NV12Scale(tmpBuffer,
+                    srcY,
+                    srcYStride,
+                    srcUV,
+                    srcUVStride,
+                    _cropWidth,
+                    _cropHeight,
+                    dstY,
+                    dstYStride,
+                    dstUV,
+                    dstUVStride,
+                    dstWidth,
+                    dstHeight);
+
+  CVPixelBufferUnlockBaseAddress(_pixelBuffer, kCVPixelBufferLock_ReadOnly);
+  CVPixelBufferUnlockBaseAddress(outputPixelBuffer, 0);
+
+  return YES;
+}
+
+- (id<RTCI420Buffer>)toI420 {
+  const OSType pixelFormat = CVPixelBufferGetPixelFormatType(_pixelBuffer);
+  RTC_DCHECK(pixelFormat == kCVPixelFormatType_420YpCbCr8BiPlanarFullRange ||
+             pixelFormat == kCVPixelFormatType_420YpCbCr8BiPlanarVideoRange);
+
+  CVPixelBufferLockBaseAddress(_pixelBuffer, kCVPixelBufferLock_ReadOnly);
+  const uint8_t* srcY =
+      static_cast<const uint8_t*>(CVPixelBufferGetBaseAddressOfPlane(_pixelBuffer, 0));
+  const int srcYStride = CVPixelBufferGetBytesPerRowOfPlane(_pixelBuffer, 0);
+  const uint8_t* srcUV =
+      static_cast<const uint8_t*>(CVPixelBufferGetBaseAddressOfPlane(_pixelBuffer, 1));
+  const int srcUVStride = CVPixelBufferGetBytesPerRowOfPlane(_pixelBuffer, 1);
+
+  // Crop just by modifying pointers.
+  srcY += srcYStride * _cropY + _cropX;
+  srcUV += srcUVStride * (_cropY / 2) + _cropX;
+
+  // TODO(magjed): Use a frame buffer pool.
+  webrtc::NV12ToI420Scaler nv12ToI420Scaler;
+  RTCMutableI420Buffer* i420Buffer =
+      [[RTCMutableI420Buffer alloc] initWithWidth:[self width] height:[self height]];
+  nv12ToI420Scaler.NV12ToI420Scale(srcY,
+                                   srcYStride,
+                                   srcUV,
+                                   srcUVStride,
+                                   _cropWidth,
+                                   _cropHeight,
+                                   i420Buffer.mutableDataY,
+                                   i420Buffer.strideY,
+                                   i420Buffer.mutableDataU,
+                                   i420Buffer.strideU,
+                                   i420Buffer.mutableDataV,
+                                   i420Buffer.strideV,
+                                   i420Buffer.width,
+                                   i420Buffer.height);
+
+  CVPixelBufferUnlockBaseAddress(_pixelBuffer, kCVPixelBufferLock_ReadOnly);
+
+  return i420Buffer;
+}
+
+@end

sdk/objc/Framework/Classes/Video/RTCDefaultShader.h

@@ -0,0 +1,23 @@
+/*
+ *  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 "WebRTC/RTCVideoViewShading.h"
+
+NS_ASSUME_NONNULL_BEGIN
+
+/** Default RTCVideoViewShading that will be used in RTCNSGLVideoView and
+ *  RTCEAGLVideoView if no external shader is specified. This shader will render
+ *  the video in a rectangle without any color or geometric transformations.
+ */
+@interface RTCDefaultShader : NSObject<RTCVideoViewShading>
+
+@end
+
+NS_ASSUME_NONNULL_END

sdk/objc/Framework/Classes/Video/RTCDefaultShader.mm

@@ -0,0 +1,207 @@
+/*
+ *  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 "RTCDefaultShader.h"
+
+#if TARGET_OS_IPHONE
+#import <OpenGLES/ES3/gl.h>
+#else
+#import <OpenGL/gl3.h>
+#endif
+
+#import "RTCOpenGLDefines.h"
+#import "RTCShader.h"
+#import "WebRTC/RTCLogging.h"
+
+#include "webrtc/api/optional.h"
+
+static const int kYTextureUnit = 0;
+static const int kUTextureUnit = 1;
+static const int kVTextureUnit = 2;
+static const int kUvTextureUnit = 1;
+
+// Fragment shader converts YUV values from input textures into a final RGB
+// pixel. The conversion formula is from http://www.fourcc.org/fccyvrgb.php.
+static const char kI420FragmentShaderSource[] =
+  SHADER_VERSION
+  "precision highp float;"
+  FRAGMENT_SHADER_IN " vec2 v_texcoord;\n"
+  "uniform lowp sampler2D s_textureY;\n"
+  "uniform lowp sampler2D s_textureU;\n"
+  "uniform lowp sampler2D s_textureV;\n"
+  FRAGMENT_SHADER_OUT
+  "void main() {\n"
+  "    float y, u, v, r, g, b;\n"
+  "    y = " FRAGMENT_SHADER_TEXTURE "(s_textureY, v_texcoord).r;\n"
+  "    u = " FRAGMENT_SHADER_TEXTURE "(s_textureU, v_texcoord).r;\n"
+  "    v = " FRAGMENT_SHADER_TEXTURE "(s_textureV, v_texcoord).r;\n"
+  "    u = u - 0.5;\n"
+  "    v = v - 0.5;\n"
+  "    r = y + 1.403 * v;\n"
+  "    g = y - 0.344 * u - 0.714 * v;\n"
+  "    b = y + 1.770 * u;\n"
+  "    " FRAGMENT_SHADER_COLOR " = vec4(r, g, b, 1.0);\n"
+  "  }\n";
+
+static const char kNV12FragmentShaderSource[] =
+  SHADER_VERSION
+  "precision mediump float;"
+  FRAGMENT_SHADER_IN " vec2 v_texcoord;\n"
+  "uniform lowp sampler2D s_textureY;\n"
+  "uniform lowp sampler2D s_textureUV;\n"
+  FRAGMENT_SHADER_OUT
+  "void main() {\n"
+  "    mediump float y;\n"
+  "    mediump vec2 uv;\n"
+  "    y = " FRAGMENT_SHADER_TEXTURE "(s_textureY, v_texcoord).r;\n"
+  "    uv = " FRAGMENT_SHADER_TEXTURE "(s_textureUV, v_texcoord).ra -\n"
+  "        vec2(0.5, 0.5);\n"
+  "    " FRAGMENT_SHADER_COLOR " = vec4(y + 1.403 * uv.y,\n"
+  "                                     y - 0.344 * uv.x - 0.714 * uv.y,\n"
+  "                                     y + 1.770 * uv.x,\n"
+  "                                     1.0);\n"
+  "  }\n";
+
+@implementation RTCDefaultShader {
+  GLuint _vertexBuffer;
+  GLuint _vertexArray;
+  // Store current rotation and only upload new vertex data when rotation changes.
+  rtc::Optional<RTCVideoRotation> _currentRotation;
+
+  GLuint _i420Program;
+  GLuint _nv12Program;
+}
+
+- (void)dealloc {
+  glDeleteProgram(_i420Program);
+  glDeleteProgram(_nv12Program);
+  glDeleteBuffers(1, &_vertexBuffer);
+  glDeleteVertexArrays(1, &_vertexArray);
+}
+
+- (BOOL)createAndSetupI420Program {
+  NSAssert(!_i420Program, @"I420 program already created");
+  _i420Program = RTCCreateProgramFromFragmentSource(kI420FragmentShaderSource);
+  if (!_i420Program) {
+    return NO;
+  }
+  GLint ySampler = glGetUniformLocation(_i420Program, "s_textureY");
+  GLint uSampler = glGetUniformLocation(_i420Program, "s_textureU");
+  GLint vSampler = glGetUniformLocation(_i420Program, "s_textureV");
+
+  if (ySampler < 0 || uSampler < 0 || vSampler < 0) {
+    RTCLog(@"Failed to get uniform variable locations in I420 shader");
+    glDeleteProgram(_i420Program);
+    _i420Program = 0;
+    return NO;
+  }
+
+  glUseProgram(_i420Program);
+  glUniform1i(ySampler, kYTextureUnit);
+  glUniform1i(uSampler, kUTextureUnit);
+  glUniform1i(vSampler, kVTextureUnit);
+
+  return YES;
+}
+
+- (BOOL)createAndSetupNV12Program {
+  NSAssert(!_nv12Program, @"NV12 program already created");
+  _nv12Program = RTCCreateProgramFromFragmentSource(kNV12FragmentShaderSource);
+  if (!_nv12Program) {
+    return NO;
+  }
+  GLint ySampler = glGetUniformLocation(_nv12Program, "s_textureY");
+  GLint uvSampler = glGetUniformLocation(_nv12Program, "s_textureUV");
+
+  if (ySampler < 0 || uvSampler < 0) {
+    RTCLog(@"Failed to get uniform variable locations in NV12 shader");
+    glDeleteProgram(_nv12Program);
+    _nv12Program = 0;
+    return NO;
+  }
+
+  glUseProgram(_nv12Program);
+  glUniform1i(ySampler, kYTextureUnit);
+  glUniform1i(uvSampler, kUvTextureUnit);
+
+  return YES;
+}
+
+- (BOOL)prepareVertexBufferWithRotation:(RTCVideoRotation)rotation {
+  if (!_vertexBuffer && !RTCCreateVertexBuffer(&_vertexBuffer, &_vertexArray)) {
+    RTCLog(@"Failed to setup vertex buffer");
+    return NO;
+  }
+#if !TARGET_OS_IPHONE
+  glBindVertexArray(_vertexArray);
+#endif
+  glBindBuffer(GL_ARRAY_BUFFER, _vertexBuffer);
+  if (!_currentRotation || rotation != *_currentRotation) {
+    _currentRotation = rtc::Optional<RTCVideoRotation>(rotation);
+    RTCSetVertexData(*_currentRotation);
+  }
+  return YES;
+}
+
+- (void)applyShadingForFrameWithWidth:(int)width
+                               height:(int)height
+                             rotation:(RTCVideoRotation)rotation
+                               yPlane:(GLuint)yPlane
+                               uPlane:(GLuint)uPlane
+                               vPlane:(GLuint)vPlane {
+  if (![self prepareVertexBufferWithRotation:rotation]) {
+    return;
+  }
+
+  if (!_i420Program && ![self createAndSetupI420Program]) {
+    RTCLog(@"Failed to setup I420 program");
+    return;
+  }
+
+  glUseProgram(_i420Program);
+
+  glActiveTexture(static_cast<GLenum>(GL_TEXTURE0 + kYTextureUnit));
+  glBindTexture(GL_TEXTURE_2D, yPlane);
+
+  glActiveTexture(static_cast<GLenum>(GL_TEXTURE0 + kUTextureUnit));
+  glBindTexture(GL_TEXTURE_2D, uPlane);
+
+  glActiveTexture(static_cast<GLenum>(GL_TEXTURE0 + kVTextureUnit));
+  glBindTexture(GL_TEXTURE_2D, vPlane);
+
+  glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
+}
+
+- (void)applyShadingForFrameWithWidth:(int)width
+                               height:(int)height
+                             rotation:(RTCVideoRotation)rotation
+                               yPlane:(GLuint)yPlane
+                              uvPlane:(GLuint)uvPlane {
+  if (![self prepareVertexBufferWithRotation:rotation]) {
+    return;
+  }
+
+  if (!_nv12Program && ![self createAndSetupNV12Program]) {
+    RTCLog(@"Failed to setup NV12 shader");
+    return;
+  }
+
+  glUseProgram(_nv12Program);
+
+  glActiveTexture(static_cast<GLenum>(GL_TEXTURE0 + kYTextureUnit));
+  glBindTexture(GL_TEXTURE_2D, yPlane);
+
+  glActiveTexture(static_cast<GLenum>(GL_TEXTURE0 + kUvTextureUnit));
+  glBindTexture(GL_TEXTURE_2D, uvPlane);
+
+  glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
+}
+
+@end

sdk/objc/Framework/Classes/Video/RTCI420Buffer+Private.h

@@ -0,0 +1,24 @@
+/*
+ *  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 "WebRTC/RTCVideoFrameBuffer.h"
+
+#include "webrtc/api/video/i420_buffer.h"
+
+NS_ASSUME_NONNULL_BEGIN
+
+@interface RTCI420Buffer ()
+
+/** Initialize an RTCI420Buffer with its backing I420BufferInterface. */
+- (instancetype)initWithFrameBuffer:(rtc::scoped_refptr<webrtc::I420BufferInterface>)i420Buffer;
+
+@end
+
+NS_ASSUME_NONNULL_END

sdk/objc/Framework/Classes/Video/RTCI420Buffer.mm

@@ -0,0 +1,108 @@
+/*
+ *  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 "WebRTC/RTCVideoFrameBuffer.h"
+
+#include "webrtc/api/video/i420_buffer.h"
+
+@implementation RTCI420Buffer {
+ @protected
+  rtc::scoped_refptr<webrtc::I420BufferInterface> _i420Buffer;
+}
+
+- (instancetype)initWithWidth:(int)width height:(int)height {
+  if (self = [super init]) {
+    _i420Buffer = webrtc::I420Buffer::Create(width, height);
+  }
+
+  return self;
+}
+
+- (instancetype)initWithWidth:(int)width
+                       height:(int)height
+                      strideY:(int)strideY
+                      strideU:(int)strideU
+                      strideV:(int)strideV {
+  if (self = [super init]) {
+    _i420Buffer = webrtc::I420Buffer::Create(width, height, strideY, strideU, strideV);
+  }
+
+  return self;
+}
+
+- (instancetype)initWithFrameBuffer:(rtc::scoped_refptr<webrtc::I420BufferInterface>)i420Buffer {
+  if (self = [super init]) {
+    _i420Buffer = i420Buffer;
+  }
+
+  return self;
+}
+
+- (int)width {
+  return _i420Buffer->width();
+}
+
+- (int)height {
+  return _i420Buffer->height();
+}
+
+- (int)strideY {
+  return _i420Buffer->StrideY();
+}
+
+- (int)strideU {
+  return _i420Buffer->StrideU();
+}
+
+- (int)strideV {
+  return _i420Buffer->StrideV();
+}
+
+- (int)chromaWidth {
+  return _i420Buffer->ChromaWidth();
+}
+
+- (int)chromaHeight {
+  return _i420Buffer->ChromaHeight();
+}
+
+- (const uint8_t *)dataY {
+  return _i420Buffer->DataY();
+}
+
+- (const uint8_t *)dataU {
+  return _i420Buffer->DataU();
+}
+
+- (const uint8_t *)dataV {
+  return _i420Buffer->DataV();
+}
+
+- (id<RTCI420Buffer>)toI420 {
+  return self;
+}
+
+@end
+
+@implementation RTCMutableI420Buffer
+
+- (uint8_t *)mutableDataY {
+  return static_cast<webrtc::I420Buffer *>(_i420Buffer.get())->MutableDataY();
+}
+
+- (uint8_t *)mutableDataU {
+  return static_cast<webrtc::I420Buffer *>(_i420Buffer.get())->MutableDataU();
+}
+
+- (uint8_t *)mutableDataV {
+  return static_cast<webrtc::I420Buffer *>(_i420Buffer.get())->MutableDataV();
+}
+
+@end

sdk/objc/Framework/Classes/Video/RTCI420TextureCache.h

@@ -0,0 +1,25 @@
+/*
+ *  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 "RTCOpenGLDefines.h"
+#import "WebRTC/RTCVideoFrame.h"
+
+@interface RTCI420TextureCache : NSObject
+
+@property(nonatomic, readonly) GLuint yTexture;
+@property(nonatomic, readonly) GLuint uTexture;
+@property(nonatomic, readonly) GLuint vTexture;
+
+- (instancetype)init NS_UNAVAILABLE;
+- (instancetype)initWithContext:(GlContextType *)context NS_DESIGNATED_INITIALIZER;
+
+- (void)uploadFrameToTextures:(RTCVideoFrame *)frame;
+
+@end

sdk/objc/Framework/Classes/Video/RTCI420TextureCache.mm

@@ -0,0 +1,155 @@
+/*
+ *  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 "RTCI420TextureCache.h"
+#import "WebRTC/RTCVideoFrameBuffer.h"
+
+#if TARGET_OS_IPHONE
+#import <OpenGLES/ES3/gl.h>
+#else
+#import <OpenGL/gl3.h>
+#endif
+
+#include <vector>
+
+// Two sets of 3 textures are used here, one for each of the Y, U and V planes. Having two sets
+// alleviates CPU blockage in the event that the GPU is asked to render to a texture that is already
+// in use.
+static const GLsizei kNumTextureSets = 2;
+static const GLsizei kNumTexturesPerSet = 3;
+static const GLsizei kNumTextures = kNumTexturesPerSet * kNumTextureSets;
+
+@implementation RTCI420TextureCache {
+  BOOL _hasUnpackRowLength;
+  GLint _currentTextureSet;
+  // Handles for OpenGL constructs.
+  GLuint _textures[kNumTextures];
+  // Used to create a non-padded plane for GPU upload when we receive padded frames.
+  std::vector<uint8_t> _planeBuffer;
+}
+
+- (GLuint)yTexture {
+  return _textures[_currentTextureSet * kNumTexturesPerSet];
+}
+
+- (GLuint)uTexture {
+  return _textures[_currentTextureSet * kNumTexturesPerSet + 1];
+}
+
+- (GLuint)vTexture {
+  return _textures[_currentTextureSet * kNumTexturesPerSet + 2];
+}
+
+- (instancetype)initWithContext:(GlContextType *)context {
+  if (self = [super init]) {
+#if TARGET_OS_IPHONE
+    _hasUnpackRowLength = (context.API == kEAGLRenderingAPIOpenGLES3);
+#else
+    _hasUnpackRowLength = YES;
+#endif
+    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+
+    [self setupTextures];
+  }
+  return self;
+}
+
+- (void)dealloc {
+  glDeleteTextures(kNumTextures, _textures);
+}
+
+- (void)setupTextures {
+  glGenTextures(kNumTextures, _textures);
+  // Set parameters for each of the textures we created.
+  for (GLsizei i = 0; i < kNumTextures; i++) {
+    glBindTexture(GL_TEXTURE_2D, _textures[i]);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+  }
+}
+
+- (void)uploadPlane:(const uint8_t *)plane
+            texture:(GLuint)texture
+              width:(size_t)width
+             height:(size_t)height
+             stride:(int32_t)stride {
+  glBindTexture(GL_TEXTURE_2D, texture);
+
+  const uint8_t *uploadPlane = plane;
+  if ((size_t)stride != width) {
+   if (_hasUnpackRowLength) {
+      // GLES3 allows us to specify stride.
+      glPixelStorei(GL_UNPACK_ROW_LENGTH, stride);
+      glTexImage2D(GL_TEXTURE_2D,
+                   0,
+                   RTC_PIXEL_FORMAT,
+                   static_cast<GLsizei>(width),
+                   static_cast<GLsizei>(height),
+                   0,
+                   RTC_PIXEL_FORMAT,
+                   GL_UNSIGNED_BYTE,
+                   uploadPlane);
+      glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
+      return;
+    } else {
+      // Make an unpadded copy and upload that instead. Quick profiling showed
+      // that this is faster than uploading row by row using glTexSubImage2D.
+      uint8_t *unpaddedPlane = _planeBuffer.data();
+      for (size_t y = 0; y < height; ++y) {
+        memcpy(unpaddedPlane + y * width, plane + y * stride, width);
+      }
+      uploadPlane = unpaddedPlane;
+    }
+  }
+  glTexImage2D(GL_TEXTURE_2D,
+               0,
+               RTC_PIXEL_FORMAT,
+               static_cast<GLsizei>(width),
+               static_cast<GLsizei>(height),
+               0,
+               RTC_PIXEL_FORMAT,
+               GL_UNSIGNED_BYTE,
+               uploadPlane);
+}
+
+- (void)uploadFrameToTextures:(RTCVideoFrame *)frame {
+  _currentTextureSet = (_currentTextureSet + 1) % kNumTextureSets;
+
+  id<RTCI420Buffer> buffer = [frame.buffer toI420];
+
+  const int chromaWidth = buffer.chromaWidth;
+  const int chromaHeight = buffer.chromaHeight;
+  if (buffer.strideY != frame.width || buffer.strideU != chromaWidth ||
+      buffer.strideV != chromaWidth) {
+    _planeBuffer.resize(buffer.width * buffer.height);
+  }
+
+  [self uploadPlane:buffer.dataY
+            texture:self.yTexture
+              width:buffer.width
+             height:buffer.height
+             stride:buffer.strideY];
+
+  [self uploadPlane:buffer.dataU
+            texture:self.uTexture
+              width:chromaWidth
+             height:chromaHeight
+             stride:buffer.strideU];
+
+  [self uploadPlane:buffer.dataV
+            texture:self.vTexture
+              width:chromaWidth
+             height:chromaHeight
+             stride:buffer.strideV];
+}
+
+@end

sdk/objc/Framework/Classes/Video/RTCNV12TextureCache.h

@@ -0,0 +1,31 @@
+/*
+ *  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 <GLKit/GLKit.h>
+
+@class RTCVideoFrame;
+
+NS_ASSUME_NONNULL_BEGIN
+
+@interface RTCNV12TextureCache : NSObject
+
+@property(nonatomic, readonly) GLuint yTexture;
+@property(nonatomic, readonly) GLuint uvTexture;
+
+- (instancetype)init NS_UNAVAILABLE;
+- (nullable instancetype)initWithContext:(EAGLContext *)context NS_DESIGNATED_INITIALIZER;
+
+- (BOOL)uploadFrameToTextures:(RTCVideoFrame *)frame;
+
+- (void)releaseTextures;
+
+@end
+
+NS_ASSUME_NONNULL_END

sdk/objc/Framework/Classes/Video/RTCNV12TextureCache.m

@@ -0,0 +1,111 @@
+/*
+ *  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 "RTCNV12TextureCache.h"
+
+#import "WebRTC/RTCVideoFrame.h"
+#import "WebRTC/RTCVideoFrameBuffer.h"
+
+@implementation RTCNV12TextureCache {
+  CVOpenGLESTextureCacheRef _textureCache;
+  CVOpenGLESTextureRef _yTextureRef;
+  CVOpenGLESTextureRef _uvTextureRef;
+}
+
+- (GLuint)yTexture {
+  return CVOpenGLESTextureGetName(_yTextureRef);
+}
+
+- (GLuint)uvTexture {
+  return CVOpenGLESTextureGetName(_uvTextureRef);
+}
+
+- (instancetype)initWithContext:(EAGLContext *)context {
+  if (self = [super init]) {
+    CVReturn ret = CVOpenGLESTextureCacheCreate(
+        kCFAllocatorDefault, NULL,
+#if COREVIDEO_USE_EAGLCONTEXT_CLASS_IN_API
+        context,
+#else
+        (__bridge void *)context,
+#endif
+        NULL, &_textureCache);
+    if (ret != kCVReturnSuccess) {
+      self = nil;
+    }
+  }
+  return self;
+}
+
+- (BOOL)loadTexture:(CVOpenGLESTextureRef *)textureOut
+        pixelBuffer:(CVPixelBufferRef)pixelBuffer
+         planeIndex:(int)planeIndex
+        pixelFormat:(GLenum)pixelFormat {
+  const int width = CVPixelBufferGetWidthOfPlane(pixelBuffer, planeIndex);
+  const int height = CVPixelBufferGetHeightOfPlane(pixelBuffer, planeIndex);
+
+  if (*textureOut) {
+    CFRelease(*textureOut);
+    *textureOut = nil;
+  }
+  CVReturn ret = CVOpenGLESTextureCacheCreateTextureFromImage(
+      kCFAllocatorDefault, _textureCache, pixelBuffer, NULL, GL_TEXTURE_2D, pixelFormat, width,
+      height, pixelFormat, GL_UNSIGNED_BYTE, planeIndex, textureOut);
+  if (ret != kCVReturnSuccess) {
+    CFRelease(*textureOut);
+    *textureOut = nil;
+    return NO;
+  }
+  NSAssert(CVOpenGLESTextureGetTarget(*textureOut) == GL_TEXTURE_2D,
+           @"Unexpected GLES texture target");
+  glBindTexture(GL_TEXTURE_2D, CVOpenGLESTextureGetName(*textureOut));
+  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+  return YES;
+}
+
+- (BOOL)uploadFrameToTextures:(RTCVideoFrame *)frame {
+  NSAssert([frame.buffer isKindOfClass:[RTCCVPixelBuffer class]],
+           @"frame must be CVPixelBuffer backed");
+  RTCCVPixelBuffer *rtcPixelBuffer = (RTCCVPixelBuffer *)frame.buffer;
+  CVPixelBufferRef pixelBuffer = rtcPixelBuffer.pixelBuffer;
+  return [self loadTexture:&_yTextureRef
+               pixelBuffer:pixelBuffer
+                planeIndex:0
+               pixelFormat:GL_LUMINANCE] &&
+         [self loadTexture:&_uvTextureRef
+               pixelBuffer:pixelBuffer
+                planeIndex:1
+               pixelFormat:GL_LUMINANCE_ALPHA];
+}
+
+- (void)releaseTextures {
+  if (_uvTextureRef) {
+    CFRelease(_uvTextureRef);
+    _uvTextureRef = nil;
+  }
+  if (_yTextureRef) {
+    CFRelease(_yTextureRef);
+    _yTextureRef = nil;
+  }
+}
+
+- (void)dealloc {
+  [self releaseTextures];
+  if (_textureCache) {
+    CFRelease(_textureCache);
+    _textureCache = nil;
+  }
+}
+
+@end
+

sdk/objc/Framework/Classes/Video/RTCOpenGLDefines.h

@@ -0,0 +1,37 @@
+/*
+ *  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.
+ */
+
+#import <Foundation/Foundation.h>
+
+#if TARGET_OS_IPHONE
+#define RTC_PIXEL_FORMAT GL_LUMINANCE
+#define SHADER_VERSION
+#define VERTEX_SHADER_IN "attribute"
+#define VERTEX_SHADER_OUT "varying"
+#define FRAGMENT_SHADER_IN "varying"
+#define FRAGMENT_SHADER_OUT
+#define FRAGMENT_SHADER_COLOR "gl_FragColor"
+#define FRAGMENT_SHADER_TEXTURE "texture2D"
+
+@class EAGLContext;
+typedef EAGLContext GlContextType;
+#else
+#define RTC_PIXEL_FORMAT GL_RED
+#define SHADER_VERSION "#version 150\n"
+#define VERTEX_SHADER_IN "in"
+#define VERTEX_SHADER_OUT "out"
+#define FRAGMENT_SHADER_IN "in"
+#define FRAGMENT_SHADER_OUT "out vec4 fragColor;\n"
+#define FRAGMENT_SHADER_COLOR "fragColor"
+#define FRAGMENT_SHADER_TEXTURE "texture"
+
+@class NSOpenGLContext;
+typedef NSOpenGLContext GlContextType;
+#endif

sdk/objc/Framework/Classes/Video/RTCShader.h

@@ -0,0 +1,20 @@
+/*
+ *  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.
+ */
+
+#import "WebRTC/RTCVideoFrame.h"
+
+RTC_EXTERN const char kRTCVertexShaderSource[];
+
+RTC_EXTERN GLuint RTCCreateShader(GLenum type, const GLchar *source);
+RTC_EXTERN GLuint RTCCreateProgram(GLuint vertexShader, GLuint fragmentShader);
+RTC_EXTERN GLuint RTCCreateProgramFromFragmentSource(const char fragmentShaderSource[]);
+RTC_EXTERN BOOL RTCCreateVertexBuffer(GLuint* vertexBuffer,
+                                      GLuint* vertexArray);
+RTC_EXTERN void RTCSetVertexData(RTCVideoRotation rotation);

sdk/objc/Framework/Classes/Video/RTCShader.mm

@@ -0,0 +1,189 @@
+/*
+ *  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.
+ */
+
+#import "RTCShader.h"
+
+#if TARGET_OS_IPHONE
+#import <OpenGLES/ES3/gl.h>
+#else
+#import <OpenGL/gl3.h>
+#endif
+
+#include <algorithm>
+#include <array>
+#include <memory>
+
+#import "RTCOpenGLDefines.h"
+
+#include "webrtc/rtc_base/checks.h"
+#include "webrtc/rtc_base/logging.h"
+
+// Vertex shader doesn't do anything except pass coordinates through.
+const char kRTCVertexShaderSource[] =
+  SHADER_VERSION
+  VERTEX_SHADER_IN " vec2 position;\n"
+  VERTEX_SHADER_IN " vec2 texcoord;\n"
+  VERTEX_SHADER_OUT " vec2 v_texcoord;\n"
+  "void main() {\n"
+  "    gl_Position = vec4(position.x, position.y, 0.0, 1.0);\n"
+  "    v_texcoord = texcoord;\n"
+  "}\n";
+
+// Compiles a shader of the given |type| with GLSL source |source| and returns
+// the shader handle or 0 on error.
+GLuint RTCCreateShader(GLenum type, const GLchar *source) {
+  GLuint shader = glCreateShader(type);
+  if (!shader) {
+    return 0;
+  }
+  glShaderSource(shader, 1, &source, NULL);
+  glCompileShader(shader);
+  GLint compileStatus = GL_FALSE;
+  glGetShaderiv(shader, GL_COMPILE_STATUS, &compileStatus);
+  if (compileStatus == GL_FALSE) {
+    GLint logLength = 0;
+    // The null termination character is included in the returned log length.
+    glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &logLength);
+    if (logLength > 0) {
+      std::unique_ptr<char[]> compileLog(new char[logLength]);
+      // The returned string is null terminated.
+      glGetShaderInfoLog(shader, logLength, NULL, compileLog.get());
+      LOG(LS_ERROR) << "Shader compile error: " << compileLog.get();
+    }
+    glDeleteShader(shader);
+    shader = 0;
+  }
+  return shader;
+}
+
+// Links a shader program with the given vertex and fragment shaders and
+// returns the program handle or 0 on error.
+GLuint RTCCreateProgram(GLuint vertexShader, GLuint fragmentShader) {
+  if (vertexShader == 0 || fragmentShader == 0) {
+    return 0;
+  }
+  GLuint program = glCreateProgram();
+  if (!program) {
+    return 0;
+  }
+  glAttachShader(program, vertexShader);
+  glAttachShader(program, fragmentShader);
+  glLinkProgram(program);
+  GLint linkStatus = GL_FALSE;
+  glGetProgramiv(program, GL_LINK_STATUS, &linkStatus);
+  if (linkStatus == GL_FALSE) {
+    glDeleteProgram(program);
+    program = 0;
+  }
+  return program;
+}
+
+// Creates and links a shader program with the given fragment shader source and
+// a plain vertex shader. Returns the program handle or 0 on error.
+GLuint RTCCreateProgramFromFragmentSource(const char fragmentShaderSource[]) {
+  GLuint vertexShader = RTCCreateShader(GL_VERTEX_SHADER, kRTCVertexShaderSource);
+  RTC_CHECK(vertexShader) << "failed to create vertex shader";
+  GLuint fragmentShader =
+      RTCCreateShader(GL_FRAGMENT_SHADER, fragmentShaderSource);
+  RTC_CHECK(fragmentShader) << "failed to create fragment shader";
+  GLuint program = RTCCreateProgram(vertexShader, fragmentShader);
+  // Shaders are created only to generate program.
+  if (vertexShader) {
+    glDeleteShader(vertexShader);
+  }
+  if (fragmentShader) {
+    glDeleteShader(fragmentShader);
+  }
+
+  // Set vertex shader variables 'position' and 'texcoord' in program.
+  GLint position = glGetAttribLocation(program, "position");
+  GLint texcoord = glGetAttribLocation(program, "texcoord");
+  if (position < 0 || texcoord < 0) {
+    glDeleteProgram(program);
+    return 0;
+  }
+
+  // Read position attribute with size of 2 and stride of 4 beginning at the start of the array. The
+  // last argument indicates offset of data within the vertex buffer.
+  glVertexAttribPointer(position, 2, GL_FLOAT, GL_FALSE, 4 * sizeof(GLfloat), (void *)0);
+  glEnableVertexAttribArray(position);
+
+  // Read texcoord attribute  with size of 2 and stride of 4 beginning at the first texcoord in the
+  // array. The last argument indicates offset of data within the vertex buffer.
+  glVertexAttribPointer(
+      texcoord, 2, GL_FLOAT, GL_FALSE, 4 * sizeof(GLfloat), (void *)(2 * sizeof(GLfloat)));
+  glEnableVertexAttribArray(texcoord);
+
+  return program;
+}
+
+BOOL RTCCreateVertexBuffer(GLuint *vertexBuffer, GLuint *vertexArray) {
+#if !TARGET_OS_IPHONE
+  glGenVertexArrays(1, vertexArray);
+  if (*vertexArray == 0) {
+    return NO;
+  }
+  glBindVertexArray(*vertexArray);
+#endif
+  glGenBuffers(1, vertexBuffer);
+  if (*vertexBuffer == 0) {
+    glDeleteVertexArrays(1, vertexArray);
+    return NO;
+  }
+  glBindBuffer(GL_ARRAY_BUFFER, *vertexBuffer);
+  glBufferData(GL_ARRAY_BUFFER, 4 * 4 * sizeof(GLfloat), NULL, GL_DYNAMIC_DRAW);
+  return YES;
+}
+
+// Set vertex data to the currently bound vertex buffer.
+void RTCSetVertexData(RTCVideoRotation rotation) {
+  // When modelview and projection matrices are identity (default) the world is
+  // contained in the square around origin with unit size 2. Drawing to these
+  // coordinates is equivalent to drawing to the entire screen. The texture is
+  // stretched over that square using texture coordinates (u, v) that range
+  // from (0, 0) to (1, 1) inclusive. Texture coordinates are flipped vertically
+  // here because the incoming frame has origin in upper left hand corner but
+  // OpenGL expects origin in bottom left corner.
+  std::array<std::array<GLfloat, 2>, 4> UVCoords = {{
+      {{0, 1}},  // Lower left.
+      {{1, 1}},  // Lower right.
+      {{1, 0}},  // Upper right.
+      {{0, 0}},  // Upper left.
+  }};
+
+  // Rotate the UV coordinates.
+  int rotation_offset;
+  switch (rotation) {
+    case RTCVideoRotation_0:
+      rotation_offset = 0;
+      break;
+    case RTCVideoRotation_90:
+      rotation_offset = 1;
+      break;
+    case RTCVideoRotation_180:
+      rotation_offset = 2;
+      break;
+    case RTCVideoRotation_270:
+      rotation_offset = 3;
+      break;
+  }
+  std::rotate(UVCoords.begin(), UVCoords.begin() + rotation_offset,
+              UVCoords.end());
+
+  const GLfloat gVertices[] = {
+      // X, Y, U, V.
+      -1, -1, UVCoords[0][0], UVCoords[0][1],
+       1, -1, UVCoords[1][0], UVCoords[1][1],
+       1,  1, UVCoords[2][0], UVCoords[2][1],
+      -1,  1, UVCoords[3][0], UVCoords[3][1],
+  };
+
+  glBufferSubData(GL_ARRAY_BUFFER, 0, sizeof(gVertices), gVertices);
+}

sdk/objc/Framework/Classes/Video/avfoundationformatmapper.h

@@ -0,0 +1,29 @@
+/*
+ *  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 <set>
+
+#import <AVFoundation/AVFoundation.h>
+#import <Foundation/Foundation.h>
+
+#include "webrtc/media/base/videocapturer.h"
+
+namespace webrtc {
+// Mapping from AVCaptureDeviceFormat to cricket::VideoFormat for given input
+// device.
+std::set<cricket::VideoFormat> GetSupportedVideoFormatsForDevice(
+    AVCaptureDevice* device);
+
+// Sets device format for the provided capture device. Returns YES/NO depending
+// on success.
+bool SetFormatForCaptureDevice(AVCaptureDevice* device,
+                               AVCaptureSession* session,
+                               const cricket::VideoFormat& format);
+}

sdk/objc/Framework/Classes/Video/avfoundationformatmapper.mm

@@ -0,0 +1,135 @@
+/*
+ *  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 "avfoundationformatmapper.h"
+
+#import "WebRTC/RTCLogging.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;
+}
+namespace webrtc {
+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;
+}
+
+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 = true;
+  [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 = false;
+    }
+
+    [device unlockForConfiguration];
+  } else {
+    RTCLogError(@"Failed to lock device %@. Error: %@", device, error.userInfo);
+    success = false;
+  }
+  [session commitConfiguration];
+
+  return success;
+}
+
+}  // namespace webrtc

sdk/objc/Framework/Classes/Video/avfoundationvideocapturer.h

@@ -0,0 +1,72 @@
+/*
+ *  Copyright 2015 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.
+ */
+
+#ifndef WEBRTC_SDK_OBJC_FRAMEWORK_CLASSES_VIDEO_AVFOUNDATIONVIDEOCAPTURER_H_
+#define WEBRTC_SDK_OBJC_FRAMEWORK_CLASSES_VIDEO_AVFOUNDATIONVIDEOCAPTURER_H_
+
+#import <AVFoundation/AVFoundation.h>
+
+#include "webrtc/api/video/video_frame.h"
+#include "webrtc/common_video/include/i420_buffer_pool.h"
+#include "webrtc/media/base/videocapturer.h"
+
+@class RTCAVFoundationVideoCapturerInternal;
+
+namespace rtc {
+class Thread;
+}  // namespace rtc
+
+namespace webrtc {
+
+class AVFoundationVideoCapturer : public cricket::VideoCapturer {
+ public:
+  AVFoundationVideoCapturer();
+  ~AVFoundationVideoCapturer();
+
+  cricket::CaptureState Start(const cricket::VideoFormat& format) override;
+  void Stop() override;
+  bool IsRunning() override;
+  bool IsScreencast() const override {
+    return false;
+  }
+  bool GetPreferredFourccs(std::vector<uint32_t> *fourccs) override {
+    fourccs->push_back(cricket::FOURCC_NV12);
+    return true;
+  }
+
+  // Returns the active capture session. Calls to the capture session should
+  // occur on the RTCDispatcherTypeCaptureSession queue in RTCDispatcher.
+  AVCaptureSession* GetCaptureSession();
+
+  // Returns whether the rear-facing camera can be used.
+  // e.g. It can't be used because it doesn't exist.
+  bool CanUseBackCamera() const;
+
+  // Switches the camera being used (either front or back).
+  void SetUseBackCamera(bool useBackCamera);
+  bool GetUseBackCamera() const;
+
+  // Converts the sample buffer into a cricket::CapturedFrame and signals the
+  // frame for capture.
+  void CaptureSampleBuffer(CMSampleBufferRef sample_buffer,
+                           webrtc::VideoRotation rotation);
+
+  // Called to adjust the size of output frames to supplied |width| and
+  // |height|. Also drops frames to make the output match |fps|.
+  void AdaptOutputFormat(int width, int height, int fps);
+
+ private:
+  RTCAVFoundationVideoCapturerInternal *_capturer;
+  webrtc::I420BufferPool _buffer_pool;
+};  // AVFoundationVideoCapturer
+
+}  // namespace webrtc
+
+#endif  // WEBRTC_SDK_OBJC_FRAMEWORK_CLASSES_VIDEO_AVFOUNDATIONVIDEOCAPTURER_H_

sdk/objc/Framework/Classes/Video/avfoundationvideocapturer.mm

@@ -0,0 +1,179 @@
+/*
+ *  Copyright 2015 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 <AVFoundation/AVFoundation.h>
+
+#import "RTCAVFoundationVideoCapturerInternal.h"
+#import "RTCDispatcher+Private.h"
+#import "WebRTC/RTCLogging.h"
+#import "WebRTC/RTCVideoFrameBuffer.h"
+
+#include "avfoundationformatmapper.h"
+
+#include "webrtc/api/video/video_rotation.h"
+#include "webrtc/rtc_base/bind.h"
+#include "webrtc/rtc_base/checks.h"
+#include "webrtc/rtc_base/logging.h"
+#include "webrtc/rtc_base/thread.h"
+#include "webrtc/sdk/objc/Framework/Classes/Video/objc_frame_buffer.h"
+
+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::AdaptOutputFormat(int width, int height, int fps) {
+  cricket::VideoFormat format(width, height, cricket::VideoFormat::FpsToInterval(fps), 0);
+  video_adapter()->OnOutputFormatRequest(format);
+}
+
+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;
+  }
+
+  int captured_width = CVPixelBufferGetWidth(image_buffer);
+  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;
+  }
+
+  RTCCVPixelBuffer* rtcPixelBuffer = [[RTCCVPixelBuffer alloc] initWithPixelBuffer:image_buffer
+                                                                      adaptedWidth:adapted_width
+                                                                     adaptedHeight:adapted_height
+                                                                         cropWidth:crop_width
+                                                                        cropHeight:crop_height
+                                                                             cropX:crop_x
+                                                                             cropY:crop_y];
+  rtc::scoped_refptr<VideoFrameBuffer> buffer =
+      new rtc::RefCountedObject<ObjCFrameBuffer>(rtcPixelBuffer);
+
+  // Applying rotation is only supported for legacy reasons and performance is
+  // not critical here.
+  if (apply_rotation() && rotation != kVideoRotation_0) {
+    buffer = I420Buffer::Rotate(*buffer->ToI420(), rotation);
+    if (rotation == kVideoRotation_90 || rotation == kVideoRotation_270) {
+      std::swap(captured_width, captured_height);
+    }
+
+    rotation = kVideoRotation_0;
+  }
+
+  OnFrame(webrtc::VideoFrame(buffer, rotation, translated_camera_time_us),
+          captured_width, captured_height);
+}
+
+}  // namespace webrtc

sdk/objc/Framework/Classes/Video/corevideo_frame_buffer.cc

@@ -0,0 +1,178 @@
+/*
+ *  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 "webrtc/sdk/objc/Framework/Classes/Video/corevideo_frame_buffer.h"
+
+#include "libyuv/convert.h"
+#include "webrtc/api/video/i420_buffer.h"
+#include "webrtc/common_video/libyuv/include/webrtc_libyuv.h"
+#include "webrtc/rtc_base/checks.h"
+#include "webrtc/rtc_base/logging.h"
+
+namespace webrtc {
+
+CoreVideoFrameBuffer::CoreVideoFrameBuffer(CVPixelBufferRef pixel_buffer,
+                                           int adapted_width,
+                                           int adapted_height,
+                                           int crop_width,
+                                           int crop_height,
+                                           int crop_x,
+                                           int crop_y)
+    : pixel_buffer_(pixel_buffer),
+      width_(adapted_width),
+      height_(adapted_height),
+      buffer_width_(CVPixelBufferGetWidth(pixel_buffer)),
+      buffer_height_(CVPixelBufferGetHeight(pixel_buffer)),
+      crop_width_(crop_width),
+      crop_height_(crop_height),
+      // Can only crop at even pixels.
+      crop_x_(crop_x & ~1),
+      crop_y_(crop_y & ~1) {
+  CVBufferRetain(pixel_buffer_);
+}
+
+CoreVideoFrameBuffer::CoreVideoFrameBuffer(CVPixelBufferRef pixel_buffer)
+    : pixel_buffer_(pixel_buffer),
+      width_(CVPixelBufferGetWidth(pixel_buffer)),
+      height_(CVPixelBufferGetHeight(pixel_buffer)),
+      buffer_width_(width_),
+      buffer_height_(height_),
+      crop_width_(width_),
+      crop_height_(height_),
+      crop_x_(0),
+      crop_y_(0) {
+  CVBufferRetain(pixel_buffer_);
+}
+
+CoreVideoFrameBuffer::~CoreVideoFrameBuffer() {
+  CVBufferRelease(pixel_buffer_);
+}
+
+VideoFrameBuffer::Type CoreVideoFrameBuffer::type() const {
+  return Type::kNative;
+}
+
+int CoreVideoFrameBuffer::width() const {
+  return width_;
+}
+
+int CoreVideoFrameBuffer::height() const {
+  return height_;
+}
+
+rtc::scoped_refptr<I420BufferInterface> CoreVideoFrameBuffer::ToI420() {
+  const OSType pixel_format = CVPixelBufferGetPixelFormatType(pixel_buffer_);
+  RTC_DCHECK(pixel_format == kCVPixelFormatType_420YpCbCr8BiPlanarFullRange ||
+             pixel_format == kCVPixelFormatType_420YpCbCr8BiPlanarVideoRange);
+
+  CVPixelBufferLockBaseAddress(pixel_buffer_, kCVPixelBufferLock_ReadOnly);
+  const uint8_t* src_y = static_cast<const uint8_t*>(
+      CVPixelBufferGetBaseAddressOfPlane(pixel_buffer_, 0));
+  const int src_y_stride = CVPixelBufferGetBytesPerRowOfPlane(pixel_buffer_, 0);
+  const uint8_t* src_uv = static_cast<const uint8_t*>(
+      CVPixelBufferGetBaseAddressOfPlane(pixel_buffer_, 1));
+  const int src_uv_stride =
+      CVPixelBufferGetBytesPerRowOfPlane(pixel_buffer_, 1);
+
+  // Crop just by modifying pointers.
+  src_y += src_y_stride * crop_y_ + crop_x_;
+  src_uv += src_uv_stride * (crop_y_ / 2) + crop_x_;
+
+  // TODO(magjed): Use a frame buffer pool.
+  NV12ToI420Scaler nv12_to_i420_scaler;
+  rtc::scoped_refptr<I420Buffer> buffer =
+      new rtc::RefCountedObject<I420Buffer>(width_, height_);
+  nv12_to_i420_scaler.NV12ToI420Scale(
+      src_y, src_y_stride,
+      src_uv, src_uv_stride,
+      crop_width_, crop_height_,
+      buffer->MutableDataY(), buffer->StrideY(),
+      buffer->MutableDataU(), buffer->StrideU(),
+      buffer->MutableDataV(), buffer->StrideV(),
+      buffer->width(), buffer->height());
+
+  CVPixelBufferUnlockBaseAddress(pixel_buffer_, kCVPixelBufferLock_ReadOnly);
+
+  return buffer;
+}
+
+bool CoreVideoFrameBuffer::RequiresCropping() const {
+  return crop_width_ != buffer_width_ || crop_height_ != buffer_height_;
+}
+
+bool CoreVideoFrameBuffer::CropAndScaleTo(
+    std::vector<uint8_t>* tmp_buffer,
+    CVPixelBufferRef output_pixel_buffer) const {
+  // Prepare output pointers.
+  RTC_DCHECK_EQ(CVPixelBufferGetPixelFormatType(output_pixel_buffer),
+                kCVPixelFormatType_420YpCbCr8BiPlanarFullRange);
+  CVReturn cv_ret = CVPixelBufferLockBaseAddress(output_pixel_buffer, 0);
+  if (cv_ret != kCVReturnSuccess) {
+    LOG(LS_ERROR) << "Failed to lock base address: " << cv_ret;
+    return false;
+  }
+  const int dst_width = CVPixelBufferGetWidth(output_pixel_buffer);
+  const int dst_height = CVPixelBufferGetHeight(output_pixel_buffer);
+  uint8_t* dst_y = reinterpret_cast<uint8_t*>(
+      CVPixelBufferGetBaseAddressOfPlane(output_pixel_buffer, 0));
+  const int dst_y_stride =
+      CVPixelBufferGetBytesPerRowOfPlane(output_pixel_buffer, 0);
+  uint8_t* dst_uv = reinterpret_cast<uint8_t*>(
+      CVPixelBufferGetBaseAddressOfPlane(output_pixel_buffer, 1));
+  const int dst_uv_stride =
+      CVPixelBufferGetBytesPerRowOfPlane(output_pixel_buffer, 1);
+
+  // Prepare source pointers.
+  const OSType src_pixel_format =
+      CVPixelBufferGetPixelFormatType(pixel_buffer_);
+  RTC_DCHECK(
+      src_pixel_format == kCVPixelFormatType_420YpCbCr8BiPlanarFullRange ||
+      src_pixel_format == kCVPixelFormatType_420YpCbCr8BiPlanarVideoRange);
+  CVPixelBufferLockBaseAddress(pixel_buffer_, kCVPixelBufferLock_ReadOnly);
+  const uint8_t* src_y = static_cast<const uint8_t*>(
+      CVPixelBufferGetBaseAddressOfPlane(pixel_buffer_, 0));
+  const int src_y_stride = CVPixelBufferGetBytesPerRowOfPlane(pixel_buffer_, 0);
+  const uint8_t* src_uv = static_cast<const uint8_t*>(
+      CVPixelBufferGetBaseAddressOfPlane(pixel_buffer_, 1));
+  const int src_uv_stride =
+      CVPixelBufferGetBytesPerRowOfPlane(pixel_buffer_, 1);
+
+  // Crop just by modifying pointers.
+  src_y += src_y_stride * crop_y_ + crop_x_;
+  src_uv += src_uv_stride * (crop_y_ / 2) + crop_x_;
+
+  if (crop_width_ == dst_width && crop_height_ == dst_height) {
+    tmp_buffer->clear();
+    tmp_buffer->shrink_to_fit();
+  } else {
+    const int src_chroma_width = (crop_width_ + 1) / 2;
+    const int src_chroma_height = (crop_height_ + 1) / 2;
+    const int dst_chroma_width = (dst_width + 1) / 2;
+    const int dst_chroma_height = (dst_height + 1) / 2;
+    tmp_buffer->resize(src_chroma_width * src_chroma_height * 2 +
+                       dst_chroma_width * dst_chroma_height * 2);
+    tmp_buffer->shrink_to_fit();
+  }
+
+  NV12Scale(tmp_buffer->data(),
+            src_y, src_y_stride,
+            src_uv, src_uv_stride,
+            crop_width_, crop_height_,
+            dst_y, dst_y_stride,
+            dst_uv, dst_uv_stride,
+            dst_width, dst_height);
+
+  CVPixelBufferUnlockBaseAddress(pixel_buffer_, kCVPixelBufferLock_ReadOnly);
+  CVPixelBufferUnlockBaseAddress(output_pixel_buffer, 0);
+
+  return true;
+}
+
+}  // namespace webrtc

sdk/objc/Framework/Classes/Video/corevideo_frame_buffer.h

@@ -0,0 +1,66 @@
+/*
+ *  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.
+ */
+
+#ifndef WEBRTC_SDK_OBJC_FRAMEWORK_CLASSES_VIDEO_COREVIDEO_FRAME_BUFFER_H_
+#define WEBRTC_SDK_OBJC_FRAMEWORK_CLASSES_VIDEO_COREVIDEO_FRAME_BUFFER_H_
+
+#include <CoreVideo/CoreVideo.h>
+
+#include <vector>
+
+#include "webrtc/common_video/include/video_frame_buffer.h"
+
+namespace webrtc {
+
+class CoreVideoFrameBuffer : public VideoFrameBuffer {
+ public:
+  explicit CoreVideoFrameBuffer(CVPixelBufferRef pixel_buffer);
+  CoreVideoFrameBuffer(CVPixelBufferRef pixel_buffer,
+                       int adapted_width,
+                       int adapted_height,
+                       int crop_width,
+                       int crop_height,
+                       int crop_x,
+                       int crop_y);
+  ~CoreVideoFrameBuffer() override;
+
+  CVPixelBufferRef pixel_buffer() { return pixel_buffer_; }
+
+  // Returns true if the internal pixel buffer needs to be cropped.
+  bool RequiresCropping() const;
+  // Crop and scales the internal pixel buffer to the output pixel buffer. The
+  // tmp buffer is used for intermediary splitting the UV channels. This
+  // function returns true if successful.
+  bool CropAndScaleTo(std::vector<uint8_t>* tmp_buffer,
+                      CVPixelBufferRef output_pixel_buffer) const;
+
+ private:
+  Type type() const override;
+  int width() const override;
+  int height() const override;
+  rtc::scoped_refptr<I420BufferInterface> ToI420() override;
+
+  CVPixelBufferRef pixel_buffer_;
+  // buffer_width/height is the actual pixel buffer resolution. The
+  // width_/height_ is the resolution we will scale to in ToI420(). Cropping
+  // happens before scaling, so: buffer_width >= crop_width >= width().
+  const int width_;
+  const int height_;
+  const int buffer_width_;
+  const int buffer_height_;
+  const int crop_width_;
+  const int crop_height_;
+  const int crop_x_;
+  const int crop_y_;
+};
+
+}  // namespace webrtc
+
+#endif  // WEBRTC_SDK_OBJC_FRAMEWORK_CLASSES_VIDEO_COREVIDEO_FRAME_BUFFER_H_

sdk/objc/Framework/Classes/Video/objc_frame_buffer.h

@@ -0,0 +1,44 @@
+/*
+ *  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.
+ */
+
+#ifndef WEBRTC_SDK_OBJC_FRAMEWORK_CLASSES_VIDEO_OBJC_FRAME_BUFFER_H_
+#define WEBRTC_SDK_OBJC_FRAMEWORK_CLASSES_VIDEO_OBJC_FRAME_BUFFER_H_
+
+#import <CoreVideo/CoreVideo.h>
+
+#include "webrtc/common_video/include/video_frame_buffer.h"
+
+@protocol RTCVideoFrameBuffer;
+
+namespace webrtc {
+
+class ObjCFrameBuffer : public VideoFrameBuffer {
+ public:
+  explicit ObjCFrameBuffer(id<RTCVideoFrameBuffer>);
+  ~ObjCFrameBuffer() override;
+
+  Type type() const override;
+
+  int width() const override;
+  int height() const override;
+
+  rtc::scoped_refptr<I420BufferInterface> ToI420() override;
+
+  id<RTCVideoFrameBuffer> wrapped_frame_buffer() const;
+
+ private:
+  id<RTCVideoFrameBuffer> frame_buffer_;
+  int width_;
+  int height_;
+};
+
+}  // namespace webrtc
+
+#endif  // WEBRTC_SDK_OBJC_FRAMEWORK_CLASSES_VIDEO_OBJC_FRAME_BUFFER_H_

sdk/objc/Framework/Classes/Video/objc_frame_buffer.mm

@@ -0,0 +1,78 @@
+/*
+ *  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.
+ */
+
+#include "webrtc/sdk/objc/Framework/Classes/Video/objc_frame_buffer.h"
+
+#import "WebRTC/RTCVideoFrameBuffer.h"
+
+namespace webrtc {
+
+namespace {
+
+/** ObjCFrameBuffer that conforms to I420BufferInterface by wrapping RTCI420Buffer */
+class ObjCI420FrameBuffer : public I420BufferInterface {
+ public:
+  explicit ObjCI420FrameBuffer(id<RTCI420Buffer> frame_buffer)
+      : frame_buffer_(frame_buffer), width_(frame_buffer.width), height_(frame_buffer.height) {}
+  ~ObjCI420FrameBuffer() override{};
+
+  int width() const override { return width_; }
+
+  int height() const override { return height_; }
+
+  const uint8_t* DataY() const override { return frame_buffer_.dataY; }
+
+  const uint8_t* DataU() const override { return frame_buffer_.dataU; }
+
+  const uint8_t* DataV() const override { return frame_buffer_.dataV; }
+
+  int StrideY() const override { return frame_buffer_.strideY; }
+
+  int StrideU() const override { return frame_buffer_.strideU; }
+
+  int StrideV() const override { return frame_buffer_.strideV; }
+
+ private:
+  id<RTCI420Buffer> frame_buffer_;
+  int width_;
+  int height_;
+};
+
+}  // namespace
+
+ObjCFrameBuffer::ObjCFrameBuffer(id<RTCVideoFrameBuffer> frame_buffer)
+    : frame_buffer_(frame_buffer), width_(frame_buffer.width), height_(frame_buffer.height) {}
+
+ObjCFrameBuffer::~ObjCFrameBuffer() {}
+
+VideoFrameBuffer::Type ObjCFrameBuffer::type() const {
+  return Type::kNative;
+}
+
+int ObjCFrameBuffer::width() const {
+  return width_;
+}
+
+int ObjCFrameBuffer::height() const {
+  return height_;
+}
+
+rtc::scoped_refptr<I420BufferInterface> ObjCFrameBuffer::ToI420() {
+  rtc::scoped_refptr<I420BufferInterface> buffer =
+      new rtc::RefCountedObject<ObjCI420FrameBuffer>([frame_buffer_ toI420]);
+
+  return buffer;
+}
+
+id<RTCVideoFrameBuffer> ObjCFrameBuffer::wrapped_frame_buffer() const {
+  return frame_buffer_;
+}
+
+}  // namespace webrtc

sdk/objc/Framework/Classes/Video/objcvideotracksource.h

@@ -0,0 +1,52 @@
+/*
+ *  Copyright (c) 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.
+ */
+
+#ifndef WEBRTC_SDK_OBJC_FRAMEWORK_CLASSES_VIDEO_OBJCVIDEOTRACKSOURCE_H_
+#define WEBRTC_SDK_OBJC_FRAMEWORK_CLASSES_VIDEO_OBJCVIDEOTRACKSOURCE_H_
+
+#include "WebRTC/RTCMacros.h"
+#include "webrtc/media/base/adaptedvideotracksource.h"
+#include "webrtc/rtc_base/timestampaligner.h"
+
+RTC_FWD_DECL_OBJC_CLASS(RTCVideoFrame);
+
+namespace webrtc {
+
+class ObjcVideoTrackSource : public rtc::AdaptedVideoTrackSource {
+ public:
+  ObjcVideoTrackSource();
+
+  // This class can not be used for implementing screen casting. Hopefully, this
+  // function will be removed before we add that to iOS/Mac.
+  bool is_screencast() const override { return false; }
+
+  // Indicates that the encoder should denoise video before encoding it.
+  // If it is not set, the default configuration is used which is different
+  // depending on video codec.
+  rtc::Optional<bool> needs_denoising() const override {
+    return rtc::Optional<bool>(false);
+  }
+
+  SourceState state() const override { return SourceState::kLive; }
+
+  bool remote() const override { return false; }
+
+  // Called by RTCVideoSource.
+  void OnCapturedFrame(RTCVideoFrame* frame);
+  void OnOutputFormatRequest(int width, int height, int fps);
+
+ private:
+  rtc::VideoBroadcaster broadcaster_;
+  rtc::TimestampAligner timestamp_aligner_;
+};
+
+}  // namespace webrtc
+
+#endif  // WEBRTC_SDK_OBJC_FRAMEWORK_CLASSES_VIDEO_OBJCVIDEOTRACKSOURCE_H_

sdk/objc/Framework/Classes/Video/objcvideotracksource.mm

@@ -0,0 +1,79 @@
+/*
+ *  Copyright (c) 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.
+ */
+
+#include "webrtc/sdk/objc/Framework/Classes/Video/objcvideotracksource.h"
+
+#import "WebRTC/RTCVideoFrame.h"
+#import "WebRTC/RTCVideoFrameBuffer.h"
+
+#include "webrtc/api/video/i420_buffer.h"
+#include "webrtc/sdk/objc/Framework/Classes/Video/objc_frame_buffer.h"
+
+namespace webrtc {
+
+ObjcVideoTrackSource::ObjcVideoTrackSource() {}
+
+void ObjcVideoTrackSource::OnOutputFormatRequest(int width, int height, int fps) {
+  cricket::VideoFormat format(width, height, cricket::VideoFormat::FpsToInterval(fps), 0);
+  video_adapter()->OnOutputFormatRequest(format);
+}
+
+void ObjcVideoTrackSource::OnCapturedFrame(RTCVideoFrame* frame) {
+  const int64_t timestamp_us = frame.timeStampNs / rtc::kNumNanosecsPerMicrosec;
+  const int64_t translated_timestamp_us =
+      timestamp_aligner_.TranslateTimestamp(timestamp_us, rtc::TimeMicros());
+
+  int adapted_width;
+  int adapted_height;
+  int crop_width;
+  int crop_height;
+  int crop_x;
+  int crop_y;
+  if (!AdaptFrame(frame.width, frame.height, timestamp_us, &adapted_width, &adapted_height,
+                  &crop_width, &crop_height, &crop_x, &crop_y)) {
+    return;
+  }
+
+  rtc::scoped_refptr<VideoFrameBuffer> buffer;
+  if (adapted_width == frame.width && adapted_height == frame.height) {
+    // No adaption - optimized path.
+    buffer = new rtc::RefCountedObject<ObjCFrameBuffer>(frame.buffer);
+  } else if ([frame.buffer isKindOfClass:[RTCCVPixelBuffer class]]) {
+    // Adapted CVPixelBuffer frame.
+    RTCCVPixelBuffer *rtcPixelBuffer = (RTCCVPixelBuffer *)frame.buffer;
+    buffer = new rtc::RefCountedObject<ObjCFrameBuffer>([[RTCCVPixelBuffer alloc]
+        initWithPixelBuffer:rtcPixelBuffer.pixelBuffer
+               adaptedWidth:adapted_width
+              adaptedHeight:adapted_height
+                  cropWidth:crop_width
+                 cropHeight:crop_height
+                      cropX:crop_x + rtcPixelBuffer.cropX
+                      cropY:crop_y + rtcPixelBuffer.cropY]);
+  } else {
+    // Adapted I420 frame.
+    // TODO(magjed): Optimize this I420 path.
+    rtc::scoped_refptr<I420Buffer> i420_buffer = I420Buffer::Create(adapted_width, adapted_height);
+    buffer = new rtc::RefCountedObject<ObjCFrameBuffer>(frame.buffer);
+    i420_buffer->CropAndScaleFrom(*buffer->ToI420(), crop_x, crop_y, crop_width, crop_height);
+    buffer = i420_buffer;
+  }
+
+  // Applying rotation is only supported for legacy reasons and performance is
+  // not critical here.
+  webrtc::VideoRotation rotation = static_cast<webrtc::VideoRotation>(frame.rotation);
+  if (apply_rotation() && rotation != kVideoRotation_0) {
+    buffer = I420Buffer::Rotate(*buffer->ToI420(), rotation);
+    rotation = kVideoRotation_0;
+  }
+
+  OnFrame(webrtc::VideoFrame(buffer, rotation, translated_timestamp_us));
+}
+
+}  // namespace webrtc