Removed Mac capture crash and memory leak.

BUG=1697,1761
R=xians@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/1465005

git-svn-id: http://webrtc.googlecode.com/svn/trunk/webrtc@4023 4adac7df-926f-26a2-2b94-8c16560cd09d

7 files changed, 232 insertions, 537 deletions

diff --git a/modules/video_capture/mac/qtkit/video_capture_qtkit.h b/modules/video_capture/mac/qtkit/video_capture_qtkit.h
index 4273c600..425835d0 100644
--- a/modules/video_capture/mac/qtkit/video_capture_qtkit.h
+++ b/modules/video_capture/mac/qtkit/video_capture_qtkit.h
@@ -12,15 +12,12 @@
 #define WEBRTC_MODULES_VIDEO_CAPTURE_MAIN_SOURCE_MAC_QTKIT_VIDEO_CAPTURE_QTKIT_H_
 
 #import <QTKit/QTKit.h>
-
 #include <stdio.h>
 
-#include "../../video_capture_impl.h"
-#include "video_capture_qtkit_utility.h"
-#include "../../device_info_impl.h"
-
+#include "webrtc/modules/video_capture/video_capture_impl.h"
+#include "webrtc/modules/video_capture/mac/qtkit/video_capture_qtkit_utility.h"
+#include "webrtc/modules/video_capture/device_info_impl.h"
 
-// Forward declaraion
 @class VideoCaptureMacQTKitObjC;
 @class VideoCaptureMacQTKitInfoObjC;
 
diff --git a/modules/video_capture/mac/qtkit/video_capture_qtkit.mm b/modules/video_capture/mac/qtkit/video_capture_qtkit.mm
index e6892321..0ff7df93 100644
--- a/modules/video_capture/mac/qtkit/video_capture_qtkit.mm
+++ b/modules/video_capture/mac/qtkit/video_capture_qtkit.mm
@@ -45,6 +45,7 @@ VideoCaptureMacQTKit::~VideoCaptureMacQTKit()
                  "~VideoCaptureMacQTKit() called");
     if(_captureDevice)
     {
+        [_captureDevice registerOwner:nil];
         [_captureDevice stopCapture];
         [_captureDevice release];
     }
@@ -79,12 +80,7 @@ int32_t VideoCaptureMacQTKit::Init(
         return -1;
     }
 
-    if(-1 == [[_captureDevice registerOwner:this]intValue])
-    {
-        WEBRTC_TRACE(webrtc::kTraceError, webrtc::kTraceVideoCapture, id,
-                     "Failed to register owner for _captureDevice");
-        return -1;
-    }
+    [_captureDevice registerOwner:this];
 
     if(0 == strcmp((char*)iDeviceUniqueIdUTF8, ""))
     {
@@ -148,8 +144,7 @@ int32_t VideoCaptureMacQTKit::Init(
 
     // at this point we know that the user has passed in a valid camera. Let's
     // set it as the current.
-    if(-1 == [[_captureDevice
-               setCaptureDeviceById:(char*)deviceUniqueIdUTF8]intValue])
+    if(![_captureDevice setCaptureDeviceById:(char*)deviceUniqueIdUTF8])
     {
         strcpy((char*)_deviceUniqueId, (char*)deviceUniqueIdUTF8);
         WEBRTC_TRACE(webrtc::kTraceError, webrtc::kTraceVideoCapture, _id,
@@ -174,19 +169,11 @@ int32_t VideoCaptureMacQTKit::StartCapture(
     _captureFrameRate = capability.maxFPS;
     _captureDelay = 120;
 
-    if(-1 == [[_captureDevice setCaptureHeight:_captureHeight
-               AndWidth:_captureWidth AndFrameRate:_captureFrameRate]intValue])
-    {
-        WEBRTC_TRACE(webrtc::kTraceInfo, webrtc::kTraceVideoCapture, _id,
-                     "Could not set width=%d height=%d frameRate=%d",
-                     _captureWidth, _captureHeight, _captureFrameRate);
-        return -1;
-    }
+    [_captureDevice setCaptureHeight:_captureHeight
+                               width:_captureWidth
+                           frameRate:_captureFrameRate];
 
-    if(-1 == [[_captureDevice startCapture]intValue])
-    {
-        return -1;
-    }
+    [_captureDevice startCapture];
     _isCapturing = true;
     return 0;
 }
@@ -194,7 +181,6 @@ int32_t VideoCaptureMacQTKit::StartCapture(
 int32_t VideoCaptureMacQTKit::StopCapture()
 {
     [_captureDevice stopCapture];
-
     _isCapturing = false;
     return 0;
 }
diff --git a/modules/video_capture/mac/qtkit/video_capture_qtkit_objc.h b/modules/video_capture/mac/qtkit/video_capture_qtkit_objc.h
index 597ca053..b8eb75b0 100644
--- a/modules/video_capture/mac/qtkit/video_capture_qtkit_objc.h
+++ b/modules/video_capture/mac/qtkit/video_capture_qtkit_objc.h
@@ -23,58 +23,38 @@
 #import <CoreFoundation/CoreFoundation.h>
 #import <CoreVideo/CoreVideo.h>
 
-#import "video_capture_recursive_lock.h"
-
 #include "video_capture_qtkit.h"
 
-@interface VideoCaptureMacQTKitObjC : NSObject{
-    // class properties
-    bool                                    _capturing;
-    int                                    _frameRate;
-    int                                    _frameWidth;
-    int                                    _frameHeight;
-    int                                    _framesDelivered;
-    int                                    _framesRendered;
-    bool                                _OSSupported;
-    bool                                _captureInitialized;
-    
-    // WebRTC Custom classes
-    webrtc::videocapturemodule::VideoCaptureMacQTKit* _owner;
-    VideoCaptureRecursiveLock*            _rLock;
-    
-    // QTKit variables
-    QTCaptureSession*                    _captureSession;
-    QTCaptureDeviceInput*                _captureVideoDeviceInput;
-    QTCaptureDecompressedVideoOutput*    _captureDecompressedVideoOutput;
-    NSArray*                            _captureDevices;
-    int                                    _captureDeviceCount;
-    char                                _captureDeviceNameUTF8[1024];
-    char                                _captureDeviceNameUniqueID[1024];
+@interface VideoCaptureMacQTKitObjC : NSObject {
+  bool _capturing;
+  int _frameRate;
+  int _frameWidth;
+  int _frameHeight;
+  int _framesDelivered;
+  int _framesRendered;
+  bool _captureInitialized;
+
+  webrtc::videocapturemodule::VideoCaptureMacQTKit* _owner;
+  NSLock* lock_;
+
+  QTCaptureSession* _captureSession;
+  QTCaptureDeviceInput* _captureVideoDeviceInput;
+  QTCaptureDecompressedVideoOutput* _captureDecompressedVideoOutput;
+  NSArray* _captureDevices;
+  int _captureDeviceCount;
+  char _captureDeviceNameUTF8[1024];
+  char _captureDeviceNameUniqueID[1024];
 }
-/**************************************************************************
- *
- *   The following functions are considered to be private.
- *
- ***************************************************************************/
-
-- (NSNumber*)getCaptureDevices;
-- (NSNumber*)initializeVideoCapture;
-- (NSNumber*)initializeVariables;
-- (void)checkOSSupported;
-
-
-/**************************************************************************
- *
- *   The following functions are considered public and to be called by the VideoCaptureMacQTKit class.
- *
- ***************************************************************************/
 
+- (void)getCaptureDevices;
+- (BOOL)initializeVideoCapture;
+- (BOOL)initializeVariables;
 
-- (NSNumber*)registerOwner:(webrtc::videocapturemodule::VideoCaptureMacQTKit*)owner;
-- (NSNumber*)setCaptureDeviceById:(char*)uniqueId;
-- (NSNumber*)setCaptureHeight:(int)height AndWidth:(int)width AndFrameRate:(int)frameRate;
-- (NSNumber*)startCapture;
-- (NSNumber*)stopCapture;
+- (void)registerOwner:(webrtc::videocapturemodule::VideoCaptureMacQTKit*)owner;
+- (BOOL)setCaptureDeviceById:(char*)uniqueId;
+- (void)setCaptureHeight:(int)height width:(int)width frameRate:(int)frameRate;
+- (void)startCapture;
+- (void)stopCapture;
 
 @end
 
diff --git a/modules/video_capture/mac/qtkit/video_capture_qtkit_objc.mm b/modules/video_capture/mac/qtkit/video_capture_qtkit_objc.mm
index 702daabd..4120335f 100644
--- a/modules/video_capture/mac/qtkit/video_capture_qtkit_objc.mm
+++ b/modules/video_capture/mac/qtkit/video_capture_qtkit_objc.mm
@@ -10,451 +10,250 @@
 
 #define DEFAULT_CAPTURE_DEVICE_INDEX    1
 #define DEFAULT_FRAME_RATE              30
-#define DEFAULT_FRAME_WIDTH                352
+#define DEFAULT_FRAME_WIDTH             352
 #define DEFAULT_FRAME_HEIGHT            288
 #define ROTATE_CAPTURED_FRAME           1
 #define LOW_QUALITY                     1
 
-#import "video_capture_qtkit_objc.h"
-#include "video_capture_qtkit_utility.h"
-#include "trace.h"
+#import "webrtc/modules/video_capture/mac/qtkit/video_capture_qtkit_objc.h"
+
+#include "webrtc/system_wrappers/interface/trace.h"
 
 using namespace webrtc;
 using namespace videocapturemodule;
 
 @implementation VideoCaptureMacQTKitObjC
 
-#pragma mark **** over-written OS methods
-
-/// ***** Objective-C. Similar to C++ constructor, although must be invoked
-///       manually.
-/// ***** Potentially returns an instance of self
--(id)init{
-    self = [super init];
-    if(nil != self)
-    {
-        [self checkOSSupported];
-        [self initializeVariables];
-    }
-    else
-    {
-        return nil;
-    }
-    return self;
+-(id)init {
+  self = [super init];
+  if (self) {
+    [self initializeVariables];
+  }
+  return self;
 }
 
-/// ***** Objective-C. Similar to C++ destructor
-/// ***** Returns nothing
 - (void)dealloc {
-    if(_captureSession)
-        [_captureSession stopRunning];
+  if (_captureSession)
+    [_captureSession stopRunning];
 
-    if (_captureVideoDeviceInput)
-    {
-        if([[_captureVideoDeviceInput device] isOpen])
-            [[_captureVideoDeviceInput device] close];
+  if (_captureVideoDeviceInput) {
+    if ([[_captureVideoDeviceInput device] isOpen])
+      [[_captureVideoDeviceInput device] close];
 
-        [_captureVideoDeviceInput release];
-    }
+    [_captureVideoDeviceInput release];
+  }
 
-    [_captureDecompressedVideoOutput release];
-    [_captureSession release];
-    [_captureDevices release];
-    [_rLock release];
+  [_captureDecompressedVideoOutput release];
+  [_captureSession release];
+  [_captureDevices release];
 
-    [super dealloc];
+  [super dealloc];
 }
 
-#pragma mark **** public methods
+#pragma mark Public methods
 
-
-
-/// ***** Registers the class's owner, which is where the delivered frames are
-///       sent
-/// ***** Returns 0 on success, -1 otherwise.
-- (NSNumber*)registerOwner:(VideoCaptureMacQTKit*)owner{
-    if(!owner){
-        return [NSNumber numberWithInt:-1];
-    }
-    _owner = owner;
-    return [NSNumber numberWithInt:0];
+- (void)registerOwner:(VideoCaptureMacQTKit*)owner {
+  [lock_ lock];
+  _owner = owner;
+  [lock_ unlock];
 }
 
-/// ***** Sets the QTCaptureSession's input device from a char*
-/// ***** Sets several member variables. Can signal the error system if one has
-///       occurred
-/// ***** Returns 0 on success, -1 otherwise.
-- (NSNumber*)setCaptureDeviceById:(char*)uniqueId{
-    if(NO == _OSSupported)
-    {
-        WEBRTC_TRACE(kTraceInfo, kTraceVideoCapture, 0,
-                     "%s:%d OS version does not support necessary APIs",
-                     __FUNCTION__, __LINE__);
-        return [NSNumber numberWithInt:0];
-    }
-
-    if(!uniqueId || (0 == strcmp("", uniqueId)))
-    {
-        WEBRTC_TRACE(kTraceInfo, kTraceVideoCapture, 0,
-                     "%s:%d  \"\" was passed in for capture device name",
-                     __FUNCTION__, __LINE__);
-        memset(_captureDeviceNameUTF8, 0, 1024);
-        return [NSNumber numberWithInt:0];
-    }
-
-    if(0 == strcmp(uniqueId, _captureDeviceNameUniqueID))
-    {
-        // camera already set
-        WEBRTC_TRACE(kTraceInfo, kTraceVideoCapture, 0,
-                     "%s:%d Capture device is already set to %s", __FUNCTION__,
-                     __LINE__, _captureDeviceNameUTF8);
-        return [NSNumber numberWithInt:0];
-    }
-
-    bool success = NO;
-    QTCaptureDevice* tempCaptureDevice;
-    for(int index = 0; index < _captureDeviceCount; index++)
-    {
-        tempCaptureDevice = (QTCaptureDevice*)[_captureDevices
-                                               objectAtIndex:index];
-        char tempCaptureDeviceId[1024] = "";
-        [[tempCaptureDevice uniqueID]
-          getCString:tempCaptureDeviceId maxLength:1024
-          encoding:NSUTF8StringEncoding];
-        if(0 == strcmp(uniqueId, tempCaptureDeviceId))
-        {
-            WEBRTC_TRACE(kTraceInfo, kTraceVideoCapture, 0,
-                         "%s:%d Found capture device id %s as index %d",
-                         __FUNCTION__, __LINE__, tempCaptureDeviceId, index);
-            success = YES;
-          [[tempCaptureDevice localizedDisplayName]
-              getCString:_captureDeviceNameUTF8
-               maxLength:1024
-                encoding:NSUTF8StringEncoding];
-          [[tempCaptureDevice uniqueID]
-              getCString:_captureDeviceNameUniqueID
-               maxLength:1024
-                encoding:NSUTF8StringEncoding];
-            break;
-        }
-
-    }
-
-    if(NO == success)
-    {
-        // camera not found
-        // nothing has been changed yet, so capture device will stay in it's
-        // state
-        WEBRTC_TRACE(kTraceInfo, kTraceVideoCapture, 0,
-                     "%s:%d Capture device id %s was not found in list of "
-                     "available devices.", __FUNCTION__, __LINE__, uniqueId);
-        return [NSNumber numberWithInt:0];
-    }
-
-    NSError* error;
-    success = [tempCaptureDevice open:&error];
-    if(!success)
-    {
-        WEBRTC_TRACE(kTraceError, kTraceVideoCapture, 0,
-                     "%s:%d Failed to open capture device: %s",
-                     __FUNCTION__, __LINE__, _captureDeviceNameUTF8);
-        return [NSNumber numberWithInt:-1];
-    }
-
-    if(_captureVideoDeviceInput)
-    {
-        [_captureVideoDeviceInput release];
-    }
-    _captureVideoDeviceInput = [[QTCaptureDeviceInput alloc]
-                                 initWithDevice:tempCaptureDevice];
-
-    success = [_captureSession addInput:_captureVideoDeviceInput error:&error];
-    if(!success)
-    {
-        WEBRTC_TRACE(kTraceError, kTraceVideoCapture, 0,
-                     "%s:%d Failed to add input from %s to the capture session",
-                     __FUNCTION__, __LINE__, _captureDeviceNameUTF8);
-        return [NSNumber numberWithInt:-1];
-    }
-
+- (BOOL)setCaptureDeviceById:(char*)uniqueId {
+  if (uniqueId == nil || !strcmp("", uniqueId)) {
     WEBRTC_TRACE(kTraceInfo, kTraceVideoCapture, 0,
-                 "%s:%d successfully added capture device: %s", __FUNCTION__,
-                 __LINE__, _captureDeviceNameUTF8);
-    return [NSNumber numberWithInt:0];
-}
-
-
-/// ***** Updates the capture devices size and frequency
-/// ***** Sets member variables _frame* and _captureDecompressedVideoOutput
-/// ***** Returns 0 on success, -1 otherwise.
-- (NSNumber*)setCaptureHeight:(int)height AndWidth:(int)width
-             AndFrameRate:(int)frameRate{
-    if(NO == _OSSupported)
-    {
-        return [NSNumber numberWithInt:0];
+                 "Incorrect capture id argument");
+    return NO;
+  }
+
+  if (!strcmp(uniqueId, _captureDeviceNameUniqueID))
+    return YES;
+
+  QTCaptureDevice* captureDevice;
+  for(int index = 0; index < _captureDeviceCount; index++) {
+    captureDevice = (QTCaptureDevice*)[_captureDevices objectAtIndex:index];
+    char captureDeviceId[1024] = "";
+    [[captureDevice uniqueID] getCString:captureDeviceId
+                               maxLength:1024
+                                encoding:NSUTF8StringEncoding];
+    if (strcmp(uniqueId, captureDeviceId) == 0) {
+      WEBRTC_TRACE(kTraceInfo, kTraceVideoCapture, 0,
+                   "%s:%d Found capture device id %s as index %d",
+                   __FUNCTION__, __LINE__, captureDeviceId, index);
+      [[captureDevice localizedDisplayName] getCString:_captureDeviceNameUTF8
+                                             maxLength:1024
+                                              encoding:NSUTF8StringEncoding];
+      [[captureDevice uniqueID] getCString:_captureDeviceNameUniqueID
+                                 maxLength:1024
+                                  encoding:NSUTF8StringEncoding];
+      break;
     }
-
-    _frameWidth = width;
-    _frameHeight = height;
-    _frameRate = frameRate;
-
-    // TODO(mflodman) Check fps settings.
-    // [_captureDecompressedVideoOutput
-    //     setMinimumVideoFrameInterval:(NSTimeInterval)1/(float)_frameRate];
-    NSDictionary* captureDictionary = [NSDictionary dictionaryWithObjectsAndKeys:
-                                       [NSNumber numberWithDouble:_frameWidth], (id)kCVPixelBufferWidthKey,
-                                       [NSNumber numberWithDouble:_frameHeight], (id)kCVPixelBufferHeightKey,
-                                       [NSNumber numberWithUnsignedInt:kCVPixelFormatType_32ARGB],
-                                       (id)kCVPixelBufferPixelFormatTypeKey, nil]; 
-    [_captureDecompressedVideoOutput performSelectorOnMainThread:@selector(setPixelBufferAttributes:) withObject:captureDictionary waitUntilDone:NO];
-//    [_captureDecompressedVideoOutput setPixelBufferAttributes:captureDictionary];
-
-        
-    // these methods return type void so there isn't much we can do about
-    // checking success
-    return [NSNumber numberWithInt:0];
+    captureDevice = nil;
+  }
+
+  if (!captureDevice)
+    return NO;
+
+  NSError* error;
+  if (![captureDevice open:&error]) {
+    WEBRTC_TRACE(kTraceError, kTraceVideoCapture, 0,
+                 "Failed to open capture device: %s", _captureDeviceNameUTF8);
+    return NO;
+  }
+
+  if (_captureVideoDeviceInput) {
+    [_captureVideoDeviceInput release];
+  }
+  _captureVideoDeviceInput =
+      [[QTCaptureDeviceInput alloc] initWithDevice:captureDevice];
+
+  if (![_captureSession addInput:_captureVideoDeviceInput error:&error]) {
+    WEBRTC_TRACE(kTraceError, kTraceVideoCapture, 0,
+                 "Failed to add input from %s to the capture session",
+                 _captureDeviceNameUTF8);
+    return NO;
+  }
+
+  WEBRTC_TRACE(kTraceInfo, kTraceVideoCapture, 0,
+               "%s:%d successfully added capture device: %s", __FUNCTION__,
+               __LINE__, _captureDeviceNameUTF8);
+  return YES;
 }
 
-/// ***** Starts the QTCaptureSession, assuming correct state. Also ensures that
-///       an NSRunLoop is running
-/// ***** Without and NSRunLoop to process events, the OS doesn't check for a
-///       new frame.
-/// ***** Sets member variables _capturing
-/// ***** Returns 0 on success, -1 otherwise.
-- (NSNumber*)startCapture{
-    if(NO == _OSSupported)
-    {
-        return [NSNumber numberWithInt:0];
-    }
-
-    if(YES == _capturing)
-    {
-        return [NSNumber numberWithInt:0];
-    }
-  
-//    NSLog(@"--------------- before ---------------");
-    [[NSRunLoop mainRunLoop] runUntilDate:[NSDate distantFuture]];
-//    NSLog(@"--------------- after ---------------");
-
-    if(NO == _captureInitialized)
-    {
-        // this should never be called..... it is initialized on class init
-        [self initializeVideoCapture];
-    }    
-    [_captureSession startRunning];
-
-    
-    _capturing = YES;
-
-    return [NSNumber numberWithInt:0];
+- (void)setCaptureHeight:(int)height width:(int)width frameRate:(int)frameRate {
+  _frameWidth = width;
+  _frameHeight = height;
+  _frameRate = frameRate;
+
+  NSDictionary* captureDictionary =
+      [NSDictionary dictionaryWithObjectsAndKeys:
+          [NSNumber numberWithDouble:_frameWidth],
+          (id)kCVPixelBufferWidthKey,
+          [NSNumber numberWithDouble:_frameHeight],
+          (id)kCVPixelBufferHeightKey,
+          [NSNumber numberWithUnsignedInt:kCVPixelFormatType_32ARGB],
+          (id)kCVPixelBufferPixelFormatTypeKey,
+          nil];
+  [_captureDecompressedVideoOutput
+      performSelectorOnMainThread:@selector(setPixelBufferAttributes:)
+                       withObject:captureDictionary
+                    waitUntilDone:YES];
 }
 
-/// ***** Stops the QTCaptureSession, assuming correct state
-/// ***** Sets member variables _capturing
-/// ***** Returns 0 on success, -1 otherwise.
-- (NSNumber*)stopCapture{
-
-    if(NO == _OSSupported)
-    {
-        return [NSNumber numberWithInt:0];
-    }
-
-    if(nil == _captureSession)
-    {
-        return [NSNumber numberWithInt:0];
-    }
+- (void)startCapture {
+  if (_capturing)
+    return;
 
-    if(NO == _capturing)
-    {
-        return [NSNumber numberWithInt:0];
-    }
-
-    if(YES == _capturing)
-    {
-        [_captureSession stopRunning];
-    }
-
-    _capturing = NO;
-    return [NSNumber numberWithInt:0];
+  [_captureSession startRunning];
+  _capturing = YES;
 }
 
-// ********** "private" functions below here **********
-#pragma mark **** "private" methods
-
-/// ***** Class member variables are initialized here
-/// ***** Returns 0 on success, -1 otherwise.
-- (NSNumber*)initializeVariables{
-
-    if(NO == _OSSupported)
-    {
-        return [NSNumber numberWithInt:0];
-    }
-
-    memset(_captureDeviceNameUTF8, 0, 1024);
-    _framesDelivered = 0;
-    _framesRendered = 0;
-    _captureDeviceCount = 0;
-    _capturing = NO;
-    _captureInitialized = NO;
-    _frameRate = DEFAULT_FRAME_RATE;
-    _frameWidth = DEFAULT_FRAME_WIDTH;
-    _frameHeight = DEFAULT_FRAME_HEIGHT;
-    _rLock = [[VideoCaptureRecursiveLock alloc] init];
-    _captureSession = [[QTCaptureSession alloc] init];
-    _captureDecompressedVideoOutput = [[QTCaptureDecompressedVideoOutput alloc]
-                                        init];
-    [_captureDecompressedVideoOutput setDelegate:self];
-
-    [self getCaptureDevices];
-    [self initializeVideoCapture];
-
-    return [NSNumber numberWithInt:0];
+- (void)stopCapture {
+  if (!_capturing)
+    return;
 
+  [_captureSession stopRunning];
+  _capturing = NO;
 }
 
-// Checks to see if the QTCaptureSession framework is available in the OS
-// If it is not, isOSSupprted = NO.
-// Throughout the rest of the class isOSSupprted is checked and functions
-// are/aren't called depending
-// The user can use weak linking to the QTKit framework and run on older
-// versions of the OS. I.E. Backwards compaitibility
-// Returns nothing. Sets member variable
-- (void)checkOSSupported{
-
-    Class osSupportedTest = NSClassFromString(@"QTCaptureSession");
-    _OSSupported = NO;
-    if(nil == osSupportedTest)
-    {
-    }
-    _OSSupported = YES;
+#pragma mark Private methods
+
+- (BOOL)initializeVariables {
+  if (NSClassFromString(@"QTCaptureSession") == nil)
+    return NO;
+
+  memset(_captureDeviceNameUTF8, 0, 1024);
+  _framesDelivered = 0;
+  _framesRendered = 0;
+  _captureDeviceCount = 0;
+  _capturing = NO;
+  _captureInitialized = NO;
+  _frameRate = DEFAULT_FRAME_RATE;
+  _frameWidth = DEFAULT_FRAME_WIDTH;
+  _frameHeight = DEFAULT_FRAME_HEIGHT;
+  lock_ = [[NSLock alloc] init];
+  _captureSession = [[QTCaptureSession alloc] init];
+  _captureDecompressedVideoOutput =
+      [[QTCaptureDecompressedVideoOutput alloc] init];
+  [_captureDecompressedVideoOutput setDelegate:self];
+
+  [self getCaptureDevices];
+  if (![self initializeVideoCapture])
+    return NO;
+
+  return NO;
 }
 
-/// ***** Retrieves the number of capture devices currently available
-/// ***** Stores them in an NSArray instance
-/// ***** Returns 0 on success, -1 otherwise.
-- (NSNumber*)getCaptureDevices{
-
-    if(NO == _OSSupported)
-    {
-        return [NSNumber numberWithInt:0];
-    }
+- (void)getCaptureDevices {
+  if (_captureDevices)
+    [_captureDevices release];
 
-    if(_captureDevices)
-    {
-        [_captureDevices release];
-    }
-    _captureDevices = [[NSArray alloc] initWithArray:
-        [QTCaptureDevice inputDevicesWithMediaType:QTMediaTypeVideo]];
+  _captureDevices = [[NSArray alloc] initWithArray:
+      [QTCaptureDevice inputDevicesWithMediaType:QTMediaTypeVideo]];
 
-    _captureDeviceCount = _captureDevices.count;
-    if(_captureDeviceCount < 1)
-    {
-        return [NSNumber numberWithInt:0];
-    }
-    return [NSNumber numberWithInt:0];
+  _captureDeviceCount = _captureDevices.count;
 }
 
-// Initializes a QTCaptureSession (member variable) to deliver frames via
-// callback
-// QTCapture* member variables affected
-// The image format and frequency are setup here
-// Returns 0 on success, -1 otherwise.
-- (NSNumber*)initializeVideoCapture{
-
-    if(YES == _captureInitialized)
-    {
-        return [NSNumber numberWithInt:-1];
-    }
-
-    bool success = NO;
-    NSError*    error;
-
-    [_captureDecompressedVideoOutput setPixelBufferAttributes:
-        [NSDictionary dictionaryWithObjectsAndKeys:
-            [NSNumber numberWithDouble:_frameWidth], (id)kCVPixelBufferWidthKey,
-            [NSNumber numberWithDouble:_frameHeight], (id)kCVPixelBufferHeightKey,
-            [NSNumber numberWithUnsignedInt:kCVPixelFormatType_32ARGB],
-            (id)kCVPixelBufferPixelFormatTypeKey, nil]];
-
-    // TODO(mflodman) Check fps settings.
-    //[_captureDecompressedVideoOutput setMinimumVideoFrameInterval:
-    //    (NSTimeInterval)1/(float)_frameRate];
-    //[_captureDecompressedVideoOutput setAutomaticallyDropsLateVideoFrames:YES];
-
-    success = [_captureSession addOutput:_captureDecompressedVideoOutput
-               error:&error];
-
-    if(!success)
-    {
-        return [NSNumber numberWithInt:-1];
-    }
-
-    _captureInitialized = YES;
+- (BOOL)initializeVideoCapture{
+  NSDictionary *captureDictionary =
+      [NSDictionary dictionaryWithObjectsAndKeys:
+          [NSNumber numberWithDouble:_frameWidth],
+          (id)kCVPixelBufferWidthKey,
+          [NSNumber numberWithDouble:_frameHeight],
+          (id)kCVPixelBufferHeightKey,
+          [NSNumber numberWithUnsignedInt:kCVPixelFormatType_32ARGB],
+          (id)kCVPixelBufferPixelFormatTypeKey,
+          nil];
+
+  [_captureDecompressedVideoOutput setPixelBufferAttributes:captureDictionary];
+  [_captureDecompressedVideoOutput setAutomaticallyDropsLateVideoFrames:YES];
+  [_captureDecompressedVideoOutput
+      setMinimumVideoFrameInterval:(NSTimeInterval)1/(float)_frameRate];
+
+  NSError *error;
+  if (![_captureSession addOutput:_captureDecompressedVideoOutput error:&error])
+    return NO;
+
+  return YES;
+}
 
-    return [NSNumber numberWithInt:0];
+- (void)captureOutput:(QTCaptureOutput *)captureOutput
+    didDropVideoFrameWithSampleBuffer:(QTSampleBuffer *)sampleBuffer
+                       fromConnection:(QTCaptureConnection *)connection {
+  // TODO(mflodman) Experiment more when this happens.
 }
 
-// This is the callback that is called when the OS has a frame to deliver to us.
-// Starts being called when [_captureSession startRunning] is called. Stopped
-// similarly.
-// Parameter videoFrame contains the image. The format, size, and frequency
-// were setup earlier.
-// Returns 0 on success, -1 otherwise.
 - (void)captureOutput:(QTCaptureOutput *)captureOutput
-    didOutputVideoFrame:(CVImageBufferRef)videoFrame
+  didOutputVideoFrame:(CVImageBufferRef)videoFrame
      withSampleBuffer:(QTSampleBuffer *)sampleBuffer
-     fromConnection:(QTCaptureConnection *)connection{
+       fromConnection:(QTCaptureConnection *)connection {
 
-    if(YES == [_rLock tryLock])
-    {
-        [_rLock lock];
-    }
-    else
-    {
-        return;
-    }
-
-    if(NO == _OSSupported)
-    {
-        return;
-    }
-
-    const int LOCK_FLAGS = 0; // documentation says to pass 0
+  [lock_ lock];
+  if (!_owner) {
+    [lock_ unlock];
+    return;
+  }
 
-    // get size of the frame
-    CVPixelBufferLockBaseAddress(videoFrame, LOCK_FLAGS);
-    void* baseAddress = CVPixelBufferGetBaseAddress(videoFrame);
+  const int kFlags = 0;
+  if (CVPixelBufferLockBaseAddress(videoFrame, kFlags) == kCVReturnSuccess) {
+    void *baseAddress = CVPixelBufferGetBaseAddress(videoFrame);
     size_t bytesPerRow = CVPixelBufferGetBytesPerRow(videoFrame);
     int frameHeight = CVPixelBufferGetHeight(videoFrame);
-    CVPixelBufferUnlockBaseAddress(videoFrame, LOCK_FLAGS);
-
-    if(_owner)
-    {
-
-        int frameSize = bytesPerRow * frameHeight;    // 32 bit ARGB format
-        CVBufferRetain(videoFrame);
-        VideoCaptureCapability tempCaptureCapability;
-        tempCaptureCapability.width = _frameWidth;
-        tempCaptureCapability.height = _frameHeight;
-        tempCaptureCapability.maxFPS = _frameRate;
-        // TODO(wu) : Update actual type and not hard-coded value. 
-        tempCaptureCapability.rawType = kVideoBGRA;
-
-        _owner->IncomingFrame((unsigned char*)baseAddress,
-                              frameSize,
-                              tempCaptureCapability,
-                              0);
-
-        CVBufferRelease(videoFrame);
-    }
-
-    _framesDelivered++;
-    _framesRendered++;
-
-    if(YES == [_rLock locked])
-    {
-        [_rLock unlock];
-    }
+    int frameSize = bytesPerRow * frameHeight;
+
+    VideoCaptureCapability tempCaptureCapability;
+    tempCaptureCapability.width = _frameWidth;
+    tempCaptureCapability.height = _frameHeight;
+    tempCaptureCapability.maxFPS = _frameRate;
+    // TODO(wu) : Update actual type and not hard-coded value.
+    tempCaptureCapability.rawType = kVideoBGRA;
+
+    _owner->IncomingFrame((unsigned char*)baseAddress, frameSize,
+                          tempCaptureCapability, 0);
+    CVPixelBufferUnlockBaseAddress(videoFrame, kFlags);
+  }
+  [lock_ unlock];
+  _framesDelivered++;
+  _framesRendered++;
 }
 
 @end
diff --git a/modules/video_capture/mac/qtkit/video_capture_recursive_lock.h b/modules/video_capture/mac/qtkit/video_capture_recursive_lock.h
deleted file mode 100644
index f4008a4d..00000000
--- a/modules/video_capture/mac/qtkit/video_capture_recursive_lock.h
+++ /dev/null
@@ -1,32 +0,0 @@
-/*
- *  Copyright (c) 2011 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.
- */
-
-//
-//  video_capture_recursive_lock.h
-//
-//
-
-#ifndef WEBRTC_MODULES_VIDEO_CAPTURE_MAIN_SOURCE_MAC_QTKIT_VIDEO_CAPTURE_RECURSIVE_LOCK_H_
-#define WEBRTC_MODULES_VIDEO_CAPTURE_MAIN_SOURCE_MAC_QTKIT_VIDEO_CAPTURE_RECURSIVE_LOCK_H_
-
-#import <Foundation/Foundation.h>
-
-@interface VideoCaptureRecursiveLock : NSRecursiveLock <NSLocking> {
-    BOOL _locked;
-}
-
-@property BOOL locked;
-
-- (void)lock;
-- (void)unlock;
-
-@end
-
-#endif // WEBRTC_MODULES_VIDEO_CAPTURE_MAIN_SOURCE_MAC_QTKIT_VIDEO_CAPTURE_RECURSIVE_LOCK_H_
diff --git a/modules/video_capture/mac/qtkit/video_capture_recursive_lock.mm b/modules/video_capture/mac/qtkit/video_capture_recursive_lock.mm
deleted file mode 100644
index d9df5cbc..00000000
--- a/modules/video_capture/mac/qtkit/video_capture_recursive_lock.mm
+++ /dev/null
@@ -1,33 +0,0 @@
-//
-//  video_capture_recursive_lock.mm
-//
-//
-
-#import "video_capture_recursive_lock.h"
-
-@implementation VideoCaptureRecursiveLock
-
-@synthesize locked = _locked;
-
-- (id)init{
-    self = [super init];
-    if(nil == self){
-        return nil;
-    }
-
-    [self setLocked:NO];
-    return self;
-}
-
-- (void)lock{
-    [self setLocked:YES];
-    [super lock];
-}
-
-- (void)unlock{
-    [self setLocked:NO];
-    [super unlock];
-}
-
-
-@end
diff --git a/modules/video_capture/video_capture.gypi b/modules/video_capture/video_capture.gypi
index 5ee04bf7..bb45a11d 100644
--- a/modules/video_capture/video_capture.gypi
+++ b/modules/video_capture/video_capture.gypi
@@ -63,8 +63,6 @@
                 'mac/qtkit/video_capture_qtkit_objc.h',
                 'mac/qtkit/video_capture_qtkit_objc.mm',
                 'mac/qtkit/video_capture_qtkit_utility.h',
-                'mac/qtkit/video_capture_recursive_lock.h',
-                'mac/qtkit/video_capture_recursive_lock.mm',
                 'mac/video_capture_mac.mm',
               ],
               'include_dirs': [