iOS AVCaptureSession实现视频录制功能

#import "RecordingVideoViewController.h" 
#import <AVFoundation/AVFoundation.h> 
#import <AssetsLibrary/AssetsLibrary.h> 
 
@interface RecordingVideoViewController ()<AVCaptureFileOutputRecordingDelegate> 
 
//会话 负责输入和输出设备之间的数据传递 
@property (strong,nonatomic) AVCaptureSession  *captureSession; 
//设备输入 负责从AVCaptureDevice获得输入数据 
@property (strong,nonatomic) AVCaptureDeviceInput  *videoCaptureDeviceInput; 
@property (strong,nonatomic) AVCaptureDeviceInput  *audioCaptureDeviceInput; 
//视频输出流 
@property (strong,nonatomic) AVCaptureMovieFileOutput  *captureMovieFileOutput; 
//相机拍摄预览图层 
@property (strong,nonatomic) AVCaptureVideoPreviewLayer  *captureVideoPreviewLayer; 
 
//自定义UI控件容器 
@property (strong,nonatomic) UIView  *viewContainer; 
//聚焦图标 
@property (strong,nonatomic) UIImageView  *focusCursor; 
//录制时长 
@property (strong,nonatomic) UILabel  *timeLabel; 
//切换前后摄像头 
@property (strong,nonatomic) UIButton  *switchCameraBtn; 
//改变焦距 
@property (strong,nonatomic) UIButton  *scaleBtn; 
//计时器 
@property (strong,nonatomic) NSTimer  *timer; 
 
 
@end 
 
@implementation RecordingVideoViewController { 
 @private 
  NSInteger _num; 
  CGFloat _kCameraScale; 
} 
 
 
- (UIView *)viewContainer { 
  if (!_viewContainer) { 
    _viewContainer = [[UIView alloc] initWithFrame:[UIScreen mainScreen].bounds]; 
     
    UIButton *takeButton = [UIButton buttonWithType:UIButtonTypeCustom]; 
    takeButton.backgroundColor = [UIColor redColor]; 
    [takeButton setTitle:@"start" forState:UIControlStateNormal]; 
    [takeButton addTarget:self action:@selector(takeButtonClick:) forControlEvents:UIControlEventTouchUpInside]; 
     
   
    _timeLabel = [[UILabel alloc] init]; 
    _timeLabel.textColor = [UIColor redColor]; 
    _timeLabel.textAlignment = NSTextAlignmentCenter; 
    _timeLabel.font = [UIFont boldSystemFontOfSize:20]; 
    _timeLabel.text = @"00:00"; 
     
     
    _switchCameraBtn = [UIButton buttonWithType:UIButtonTypeCustom]; 
    [_switchCameraBtn setTitle:@"switch" forState:UIControlStateNormal]; 
    _switchCameraBtn.backgroundColor = [UIColor redColor]; 
    [_switchCameraBtn addTarget:self action:@selector(switchCameraBtnClick) forControlEvents:UIControlEventTouchUpInside]; 
     
    _scaleBtn = [UIButton buttonWithType:UIButtonTypeCustom]; 
    [_scaleBtn setTitle:@"1X" forState:UIControlStateNormal]; 
    _scaleBtn.backgroundColor = [UIColor redColor]; 
    [_scaleBtn addTarget:self action:@selector(scaleBtnClick:) forControlEvents:UIControlEventTouchUpInside]; 
     
    [_viewContainer addSubview:takeButton]; 
    [_viewContainer addSubview:_timeLabel]; 
    [_viewContainer addSubview:_scaleBtn]; 
    [_viewContainer addSubview:_switchCameraBtn]; 
    [takeButton mas_makeConstraints:^(MASConstraintMaker *make) { 
      make.size.mas_equalTo(CGSizeMake(60, 40)); 
      make.centerX.mas_equalTo(_viewContainer); 
      make.bottom.mas_equalTo(_viewContainer).offset(-64); 
    }]; 
    [_timeLabel mas_makeConstraints:^(MASConstraintMaker *make) { 
      make.centerX.mas_equalTo(_viewContainer); 
      make.height.mas_equalTo(@30); 
      make.top.mas_equalTo(_viewContainer); 
    }]; 
    [_scaleBtn mas_makeConstraints:^(MASConstraintMaker *make) { 
      make.size.mas_equalTo(CGSizeMake(60, 40)); 
      make.left.mas_equalTo(_viewContainer).offset(10); 
      make.top.mas_equalTo(_viewContainer); 
    }]; 
    [_switchCameraBtn mas_makeConstraints:^(MASConstraintMaker *make) { 
      make.size.mas_equalTo(CGSizeMake(60, 40)); 
      make.top.mas_equalTo(_viewContainer); 
      make.right.mas_equalTo(_viewContainer).offset(-10); 
    }]; 
     
    _focusCursor = [[UIImageView alloc] init]; 
    kBorder(_focusCursor, 1, [UIColor yellowColor]); 
    _focusCursor.alpha = 0; 
    [_viewContainer addSubview:self.focusCursor]; 
    [_focusCursor mas_makeConstraints:^(MASConstraintMaker *make) { 
      make.size.mas_equalTo(CGSizeMake(40, 40)); 
      make.center.mas_equalTo(_viewContainer); 
    }]; 
 
  } 
  return _viewContainer; 
} 
 
- (void)viewDidLoad { 
  [super viewDidLoad]; 
   
  self.title = @"视频录制"; 
  _kCameraScale = 1.0f; 
  //初始化会话对象 
  _captureSession = [[AVCaptureSession alloc] init]; 
  if ([_captureSession canSetSessionPreset:AVCaptureSessionPreset1280x720]) { 
    _captureSession.sessionPreset = AVCaptureSessionPreset1280x720; 
  } 
   
   
  NSError *error = nil; 
 
  //获取视频输入对象 
  AVCaptureDevice *videoCaptureDevice = [self cameraDeviceWithPosition:(AVCaptureDevicePositionBack)]; 
  if (!videoCaptureDevice) { 
    NSLog(@"获取后置摄像头失败！"); 
    return; 
  } 
  _videoCaptureDeviceInput = [[AVCaptureDeviceInput alloc] initWithDevice:videoCaptureDevice error:&error]; 
  if (error) { 
    NSLog(@"取得视频设备输入对象时出错"); 
    return; 
  } 
   
   
  //获取音频输入对象 
  AVCaptureDevice *audioCatureDevice = [[AVCaptureDevice devicesWithMediaType:AVMediaTypeAudio] firstObject]; 
  _audioCaptureDeviceInput = [[AVCaptureDeviceInput alloc] initWithDevice:audioCatureDevice error:&error]; 
  if (error) { 
    NSLog(@"取得音频设备输入对象时出错"); 
    return; 
  } 
   
  //初始化设备输出对象 
  _captureMovieFileOutput = [[AVCaptureMovieFileOutput alloc] init]; 
   
  //将设备输入添加到会话中 
  if ([_captureSession canAddInput:_videoCaptureDeviceInput]) { 
    [_captureSession addInput:_videoCaptureDeviceInput]; 
    [_captureSession addInput:_audioCaptureDeviceInput]; 
     
    //防抖功能 
    AVCaptureConnection *captureConnection = [_captureMovieFileOutput connectionWithMediaType:AVMediaTypeAudio]; 
    if ([captureConnection isVideoStabilizationSupported]) { 
      captureConnection.preferredVideoStabilizationMode = AVCaptureVideoStabilizationModeAuto; 
    } 
  } 
   
  //将设备输出添加到会话中 
  if ([_captureSession canAddOutput:_captureMovieFileOutput]) { 
    [_captureSession addOutput:_captureMovieFileOutput]; 
  } 
   
   
  //创建视频预览图层 
  _captureVideoPreviewLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:_captureSession]; 
  self.viewContainer.layer.masksToBounds = YES; 
  _captureVideoPreviewLayer.frame = self.viewContainer.bounds; 
  _captureVideoPreviewLayer.videoGravity = AVLayerVideoGravityResizeAspectFill; 
  [self.view.layer addSublayer:_captureVideoPreviewLayer]; 
   
  //显示自定义控件 
  [self.view addSubview:self.viewContainer]; 
   
  //添加点按聚焦手势 
  UITapGestureRecognizer *tapGesture = [[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(tapScreen:)]; 
  [self.viewContainer addGestureRecognizer:tapGesture]; 
   
} 
 
-(void)viewDidAppear:(BOOL)animated{ 
  [super viewDidAppear:animated]; 
  [self.captureSession startRunning]; 
} 
 
-(void)viewDidDisappear:(BOOL)animated{ 
  [super viewDidDisappear:animated]; 
  [self.captureSession stopRunning]; 
  [self.timer invalidate]; 
  self.timer = nil; 
} 
 
- (void)viewWillDisappear:(BOOL)animated { 
  [super viewWillDisappear:animated]; 
  [self.captureVideoPreviewLayer setAffineTransform:CGAffineTransformMakeScale(1, 1)]; 
} 
 
- (void)didReceiveMemoryWarning { 
  [super didReceiveMemoryWarning]; 
} 
 
//开始 + 暂停录制 
- (void)takeButtonClick:(UIButton *)sender { 
  if ([self.captureMovieFileOutput isRecording]) { 
    [self.captureMovieFileOutput stopRecording]; 
     
    [self.navigationController popViewControllerAnimated:YES]; 
     
  } else { 
    AVCaptureConnection *captureConnection = [self.captureMovieFileOutput connectionWithMediaType:AVMediaTypeVideo]; 
    captureConnection.videoOrientation = [self.captureVideoPreviewLayer connection].videoOrientation; 
     
    NSString *filePath = [NSTemporaryDirectory() stringByAppendingPathComponent:@"Movie.mov"]; 
    NSLog(@"%@",filePath); 
    [self.captureMovieFileOutput startRecordingToOutputFileURL:[NSURL fileURLWithPath:filePath] recordingDelegate:self]; 
     
     
    self.switchCameraBtn.hidden = YES; 
     
    sender.backgroundColor = [UIColor greenColor]; 
    [sender setTitle:@"stop" forState:UIControlStateNormal]; 
     
    self.timer = [NSTimer scheduledTimerWithTimeInterval:1 target:self selector:@selector(timeAction) userInfo:nil repeats:YES]; 
    [self.timer setFireDate:[NSDate distantPast]]; 
  } 
} 
 
//切换摄像头 
- (void)switchCameraBtnClick { 
  AVCaptureDevicePosition currentPosition = self.videoCaptureDeviceInput.device.position; 
  AVCaptureDevicePosition toPosition; 
  if (currentPosition == AVCaptureDevicePositionUnspecified || 
    currentPosition == AVCaptureDevicePositionFront) { 
    toPosition = AVCaptureDevicePositionBack; 
  } else { 
    toPosition = AVCaptureDevicePositionFront; 
  } 
   
  AVCaptureDevice *toCapturDevice = [self cameraDeviceWithPosition:toPosition]; 
  if (!toCapturDevice) { 
    NSLog(@"获取要切换的设备失败"); 
    return; 
  } 
   
  NSError *error = nil; 
  AVCaptureDeviceInput *toVideoDeviceInput = [[AVCaptureDeviceInput alloc] initWithDevice:toCapturDevice error:&error]; 
  if (error) { 
    NSLog(@"获取要切换的设备输入失败"); 
    return; 
  } 
   
  //改变会话配置 
  [self.captureSession beginConfiguration]; 
   
  [self.captureSession removeInput:self.videoCaptureDeviceInput]; 
  if ([self.captureSession canAddInput:toVideoDeviceInput]) { 
    [self.captureSession addInput:toVideoDeviceInput]; 
     
    self.videoCaptureDeviceInput = toVideoDeviceInput; 
  } 
  //提交会话配置 
  [self.captureSession commitConfiguration]; 
} 
 
 
//点按手势 
- (void)tapScreen:(UITapGestureRecognizer *)tap { 
  CGPoint point = [tap locationInView:self.viewContainer]; 
   
  //将界面point对应到摄像头point 
  CGPoint cameraPoint = [self.captureVideoPreviewLayer captureDevicePointOfInterestForPoint:point]; 
 
  //设置聚光动画 
  self.focusCursor.center = point; 
  self.focusCursor.transform = CGAffineTransformMakeScale(1.5, 1.5); 
  self.focusCursor.alpha = 1.0f; 
  [UIView animateWithDuration:1 animations:^{ 
    self.focusCursor.transform = CGAffineTransformIdentity; 
  } completion:^(BOOL finished) { 
    self.focusCursor.alpha = 0.0f; 
 
  }]; 
   
  //设置聚光点坐标 
  [self focusWithMode:AVCaptureFocusModeAutoFocus exposureMode:AVCaptureExposureModeAutoExpose atPoint:cameraPoint]; 
 
} 
 
 
/**设置聚焦点*/ 
-(void)focusWithMode:(AVCaptureFocusMode)focusMode exposureMode:(AVCaptureExposureMode)exposureMode atPoint:(CGPoint)point{ 
   
  AVCaptureDevice *captureDevice= [self.videoCaptureDeviceInput device]; 
  NSError *error = nil; 
  //设置设备属性必须先解锁 然后加锁 
  if ([captureDevice lockForConfiguration:&error]) { 
     
    if ([captureDevice isFocusModeSupported:focusMode]) { 
      [captureDevice setFocusMode:focusMode]; 
    } 
    if ([captureDevice isFocusPointOfInterestSupported]) { 
      [captureDevice setFocusPointOfInterest:point]; 
    } 
    //    //曝光 
    //    if ([captureDevice isExposureModeSupported:exposureMode]) { 
    //      [captureDevice setExposureMode:exposureMode]; 
    //    } 
    //    if ([captureDevice isExposurePointOfInterestSupported]) { 
    //      [captureDevice setExposurePointOfInterest:point]; 
    //    } 
    //    //闪光灯模式 
    //    if ([captureDevice isFlashModeSupported:AVCaptureFlashModeAuto]) { 
    //      [captureDevice setFlashMode:AVCaptureFlashModeAuto]; 
    //    } 
     
    //加锁 
    [captureDevice unlockForConfiguration]; 
     
  }else{ 
    NSLog(@"设置设备属性过程发生错误，错误信息：%@",error.localizedDescription); 
  } 
} 
 
 
 
//调整焦距 
-(void)scaleBtnClick:(UIButton *)sender 
{ 
  _kCameraScale += 0.5; 
  if(_kCameraScale > 3.0) { 
    _kCameraScale = 1.0; 
  } 
  //改变焦距 
  AVCaptureDevice *videoDevice = self.videoCaptureDeviceInput.device; 
  NSError *error = nil; 
  if ([videoDevice lockForConfiguration:&error]) { 
     
    [videoDevice setVideoZoomFactor:_kCameraScale]; 
     
    [videoDevice unlockForConfiguration]; 
     
    [sender setTitle:[NSString stringWithFormat:@"%lgX",_kCameraScale] forState:UIControlStateNormal]; 
 
    [CATransaction begin]; 
    [CATransaction setAnimationDuration:0.25]; 
    [self.captureVideoPreviewLayer setAffineTransform:CGAffineTransformMakeScale(_kCameraScale, _kCameraScale)]; 
    [CATransaction commit]; 
     
  } else { 
    NSLog(@"修改设备属性失败!") 
  } 
} 
 
 
 
#pragma mark -------- AVCaptureFileOutputRecordingDelegate ---------- 
- (void)captureOutput:(AVCaptureFileOutput *)captureOutput didStartRecordingToOutputFileAtURL:(NSURL *)fileURL fromConnections:(NSArray *)connections { 
  NSLog(@"开始录制"); 
} 
 
- (void)captureOutput:(AVCaptureFileOutput *)captureOutput didFinishRecordingToOutputFileAtURL:(NSURL *)outputFileURL fromConnections:(NSArray *)connections error:(NSError *)error { 
  NSLog(@"录制结束"); 
  ALAssetsLibrary *assetsLibrary = [[ALAssetsLibrary alloc] init]; 
  [assetsLibrary writeVideoAtPathToSavedPhotosAlbum:outputFileURL completionBlock:^(NSURL *assetURL, NSError *error) { 
    if (error) { 
      NSLog(@"保存视频到相簿过程中发生错误，错误信息：%@",error.localizedDescription); 
    } 
  }]; 
} 
 
//录制计时 
- (void)timeAction { 
  self.timeLabel.text = [NSString stringWithFormat:@"%.2ld:%.2ld",_num/60,_num%60]; 
  _num ++; 
} 
 
 
/**取得指定位置的摄像头*/ 
- (AVCaptureDevice *)cameraDeviceWithPosition:(AVCaptureDevicePosition )position{ 
  NSArray *cameras = [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo]; 
  for (AVCaptureDevice *camera in cameras) { 
    if ([camera position] == position) { 
      return camera; 
    } 
  } 
  return nil; 
} 
  
@end 

#import "VideoTestViewController.h" 
#import <AVFoundation/AVFoundation.h> 
#import <AssetsLibrary/AssetsLibrary.h> 
 
typedef void(^PropertyChangeBlock)(AVCaptureDevice *captureDevice); 
 
@interface VideoTestViewController ()<AVCaptureFileOutputRecordingDelegate>//视频文件输出代理 
 
@property (strong,nonatomic) AVCaptureSession *captureSession;//负责输入和输出设备之间的数据传递 
@property (strong,nonatomic) AVCaptureDeviceInput *captureDeviceInput;//负责从AVCaptureDevice获得输入数据 
@property (strong,nonatomic) AVCaptureMovieFileOutput *captureMovieFileOutput;//视频输出流 
@property (strong,nonatomic) AVCaptureVideoPreviewLayer *captureVideoPreviewLayer;//相机拍摄预览图层 
 
@property (assign,nonatomic) BOOL enableRotation;//是否允许旋转（注意在视频录制过程中禁止屏幕旋转） 
@property (assign,nonatomic) CGRect *lastBounds;//旋转的前大小 
@property (assign,nonatomic) UIBackgroundTaskIdentifier backgroundTaskIdentifier;//后台任务标识 
@property (strong,nonatomic) UIView *viewContainer; 
@property (strong,nonatomic) UIButton *takeButton;//拍照按钮 
@property (strong,nonatomic) UIImageView *focusCursor; //聚焦光标 
 
 
@end 
 
@implementation VideoTestViewController 
 
#pragma mark - 控制器视图方法 
- (void)viewDidLoad { 
  [super viewDidLoad]; 
} 
 
-(void)viewWillAppear:(BOOL)animated{ 
  [super viewWillAppear:animated]; 
   
  //初始化会话 
  _captureSession=[[AVCaptureSession alloc]init]; 
  if ([_captureSession canSetSessionPreset:AVCaptureSessionPreset1280x720]) {//设置分辨率 
    _captureSession.sessionPreset=AVCaptureSessionPreset1280x720; 
  } 
  //获得输入设备 
  AVCaptureDevice *captureDevice=[self getCameraDeviceWithPosition:AVCaptureDevicePositionBack];//取得后置摄像头 
  if (!captureDevice) { 
    NSLog(@"取得后置摄像头时出现问题."); 
    return; 
  } 
  //添加一个音频输入设备 
  AVCaptureDevice *audioCaptureDevice=[[AVCaptureDevice devicesWithMediaType:AVMediaTypeAudio] firstObject]; 
   
   
  NSError *error=nil; 
  //根据输入设备初始化设备输入对象，用于获得输入数据 
  _captureDeviceInput=[[AVCaptureDeviceInput alloc]initWithDevice:captureDevice error:&error]; 
  if (error) { 
    NSLog(@"取得设备输入对象时出错，错误原因：%@",error.localizedDescription); 
    return; 
  } 
  AVCaptureDeviceInput *audioCaptureDeviceInput=[[AVCaptureDeviceInput alloc]initWithDevice:audioCaptureDevice error:&error]; 
  if (error) { 
    NSLog(@"取得设备输入对象时出错，错误原因：%@",error.localizedDescription); 
    return; 
  } 
  //初始化设备输出对象，用于获得输出数据 
  _captureMovieFileOutput=[[AVCaptureMovieFileOutput alloc]init]; 
   
  //将设备输入添加到会话中 
  if ([_captureSession canAddInput:_captureDeviceInput]) { 
    [_captureSession addInput:_captureDeviceInput]; 
    [_captureSession addInput:audioCaptureDeviceInput]; 
    AVCaptureConnection *captureConnection=[_captureMovieFileOutput connectionWithMediaType:AVMediaTypeVideo]; 
    if ([captureConnection isVideoStabilizationSupported ]) { 
      captureConnection.preferredVideoStabilizationMode=AVCaptureVideoStabilizationModeAuto; 
    } 
  } 
   
  //将设备输出添加到会话中 
  if ([_captureSession canAddOutput:_captureMovieFileOutput]) { 
    [_captureSession addOutput:_captureMovieFileOutput]; 
  } 
   
  //创建视频预览层，用于实时展示摄像头状态 
  _captureVideoPreviewLayer=[[AVCaptureVideoPreviewLayer alloc]initWithSession:self.captureSession]; 
   
  CALayer *layer=self.viewContainer.layer; 
  layer.masksToBounds=YES; 
   
  _captureVideoPreviewLayer.frame=layer.bounds; 
  _captureVideoPreviewLayer.videoGravity=AVLayerVideoGravityResizeAspectFill;//填充模式 
  //将视频预览层添加到界面中 
  //[layer addSublayer:_captureVideoPreviewLayer]; 
  [layer insertSublayer:_captureVideoPreviewLayer below:self.focusCursor.layer]; 
   
  _enableRotation=YES; 
  [self addNotificationToCaptureDevice:captureDevice]; 
  [self addGenstureRecognizer]; 
} 
 
-(void)viewDidAppear:(BOOL)animated{ 
  [super viewDidAppear:animated]; 
  [self.captureSession startRunning]; 
} 
 
-(void)viewDidDisappear:(BOOL)animated{ 
  [super viewDidDisappear:animated]; 
  [self.captureSession stopRunning]; 
} 
 
- (void)didReceiveMemoryWarning { 
  [super didReceiveMemoryWarning]; 
} 
 
-(BOOL)shouldAutorotate{ 
  return self.enableRotation; 
} 
 
////屏幕旋转时调整视频预览图层的方向 
//-(void)willTransitionToTraitCollection:(UITraitCollection *)newCollection withTransitionCoordinator:(id<UIViewControllerTransitionCoordinator>)coordinator{ 
//  [super willTransitionToTraitCollection:newCollection withTransitionCoordinator:coordinator]; 
////  NSLog(@"%i,%i",newCollection.verticalSizeClass,newCollection.horizontalSizeClass); 
//  UIInterfaceOrientation orientation = [[UIApplication sharedApplication] statusBarOrientation]; 
//  NSLog(@"%i",orientation); 
//  AVCaptureConnection *captureConnection=[self.captureVideoPreviewLayer connection]; 
//  captureConnection.videoOrientation=orientation; 
// 
/