iOS 自定义相机功能

导入相机的API在AVFoundation里所以得包含头文件#import

1.自定义相机需要的属性

@interface CustomCameraVC ()

//捕获设备,通常是前置摄像头,后置摄像头,麦克风(音频输入)
@property(nonatomic)AVCaptureDevice *device;

//AVCaptureDeviceInput 代表输入设备,他使用AVCaptureDevice 来初始化
@property(nonatomic)AVCaptureDeviceInput *input;

//当启动摄像头开始捕获输入
@property(nonatomic)AVCaptureMetadataOutput *output;

//照片输出流
@property (nonatomic)AVCapturePhotoOutput *ImageOutPut;

//session:由他把输入输出结合在一起,并开始启动捕获设备(摄像头)
@property(nonatomic)AVCaptureSession *session;

//图像预览层,实时显示捕获的图像
@property(nonatomic)AVCaptureVideoPreviewLayer *previewLayer;

// ------------- UI --------------
//拍照按钮
@property (nonatomic)UIButton *photoButton;
//闪光灯按钮
@property (nonatomic)UIButton *flashButton;
//聚焦
@property (nonatomic)UIView *focusView;
//是否开启闪光灯
@property (nonatomic)BOOL isflashOn;

@end

2.判断相机权限

#pragma mark- 检测相机权限,自动跳到设置里。
- (BOOL)checkCameraPermission
{
    AVAuthorizationStatus authStatus = [AVCaptureDevice authorizationStatusForMediaType:AVMediaTypeVideo];
    if (authStatus == AVAuthorizationStatusDenied) {
        UIAlertView *alertView = [[UIAlertView alloc]initWithTitle:@"请打开相机权限" message:@"设置-隐私-相机" delegate:self cancelButtonTitle:@"确定" otherButtonTitles:@"取消", nil];
        alertView.tag = 100;
        [alertView show];
        return NO;
    }
    else{
        return YES;
    }
    return YES;
}

- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex{
    if (buttonIndex == 0 && alertView.tag == 100) {
        
        NSURL * url = [NSURL URLWithString:UIApplicationOpenSettingsURLString];
        
        if([[UIApplication sharedApplication] canOpenURL:url]) {
            
            [[UIApplication sharedApplication] openURL:url];
            
        }
    }
    
    if (buttonIndex == 1 && alertView.tag == 100) {
        
        [self disMiss];
    }
    
}

3.创建相机属性

- (void)customCamera
{
    //使用AVMediaTypeVideo 指明self.device代表视频,默认使用后置摄像头进行初始化
    self.device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
    //使用设备初始化输入
    self.input = [[AVCaptureDeviceInput alloc]initWithDevice:self.device error:nil];
    //生成输出对象
    self.output = [[AVCaptureMetadataOutput alloc]init];
    

  //照片输出
    _capturePhotoOutput = [[AVCapturePhotoOutput alloc]init];
    NSDictionary *outputformat = [[NSDictionary alloc] initWithObjectsAndKeys: AVVideoCodecJPEG, AVVideoCodecKey, nil];
    AVCapturePhotoSettings *outputSettings = [AVCapturePhotoSettings photoSettingsWithFormat:outputformat];
    //自动闪光
    [outputSettings setFlashMode:AVCaptureFlashModeAuto];
    [_capturePhotoOutput capturePhotoWithSettings:outputSettings delegate:self];
 


    //生成会话,用来结合输入输出
    self.session = [[AVCaptureSession alloc]init];
    //直接设置质量最高 不指定,免得有些旧设备崩溃
    if ([self.session canSetSessionPreset:AVCaptureSessionPresetHigh]) {
        
        [self.session setSessionPreset:AVCaptureSessionPresetHigh];
        
    }
    
    if ([self.session canAddInput:self.input]) {
        [self.session addInput:self.input];
        
    }
   
      //将设备输出添加到会话中
    if ([_captureSession canAddOutput:_capturePhotoOutput]) {
        [_captureSession addOutput:_capturePhotoOutput];
    }

    //使用self.session,初始化预览层,self.session负责驱动input进行信息的采集,layer负责把图像渲染显示
    self.previewLayer = [[AVCaptureVideoPreviewLayer alloc]initWithSession:self.session];
    self.previewLayer.frame = CGRectMake(0, 0, KScreenWidth, KScreenHeight);
    self.previewLayer.videoGravity = AVLayerVideoGravityResizeAspectFill;
    [self.view.layer addSublayer:self.previewLayer];
    
    //开始启动
    [self.session startRunning];
    
    //修改设备的属性,先加锁
    if ([self.device lockForConfiguration:nil]) {
     
        //自动白平衡
        if ([self.device isWhiteBalanceModeSupported:AVCaptureWhiteBalanceModeAutoWhiteBalance]) {
            [self.device setWhiteBalanceMode:AVCaptureWhiteBalanceModeAutoWhiteBalance];
        }
        
        //解锁
        [self.device unlockForConfiguration];
        
        
    }
    
}

4.点击屏幕对焦 (这里差不多就是 和系统动画一样,点击屏幕时,设置view动画和device的point)

- (void)focusGesture:(UITapGestureRecognizer*)gesture{
   CGPoint point = [gesture locationInView:gesture.view];
   [self focusAtPoint:point];
}
- (void)focusAtPoint:(CGPoint)point{
   CGSize size = self.view.bounds.size;
   // focusPoint 函数后面Point取值范围是取景框左上角(0,0)到取景框右下角(1,1)之间,按这个来但位置就是不对,只能按上面的写法才可以。前面是点击位置的y/PreviewLayer的高度,后面是1-点击位置的x/PreviewLayer的宽度
   CGPoint focusPoint = CGPointMake( point.y /size.height ,1 - point.x/size.width );
   
   if ([self.device lockForConfiguration:nil]) {
       
       if ([self.device isFocusModeSupported:AVCaptureFocusModeAutoFocus]) {
           [self.device setFocusPointOfInterest:focusPoint];
           [self.device setFocusMode:AVCaptureFocusModeAutoFocus];
       }
       
       if ([self.device isExposureModeSupported:AVCaptureExposureModeAutoExpose ]) {
           [self.device setExposurePointOfInterest:focusPoint];
           //曝光量调节
           [self.device setExposureMode:AVCaptureExposureModeAutoExpose];
       }
       
       [self.device unlockForConfiguration];
       _focusView.center = point;
       _focusView.hidden = NO;
       [UIView animateWithDuration:0.3 animations:^{
           _focusView.transform = CGAffineTransformMakeScale(1.25, 1.25);
       }completion:^(BOOL finished) {
           [UIView animateWithDuration:0.5 animations:^{
               _focusView.transform = CGAffineTransformIdentity;
           } completion:^(BOOL finished) {
               _focusView.hidden = YES;
           }];
       }];
   }
   
}

5.开启闪光灯

- (void)FlashOn{
    
    if ([_device lockForConfiguration:nil]) {
        if (_isflashOn) {
            if ([_device isFlashModeSupported:AVCaptureFlashModeOff]) {
                [_device setFlashMode:AVCaptureFlashModeOff];
                _isflashOn = NO;
                [_flashButton setTitle:@"闪光灯关" forState:UIControlStateNormal];
            }
        }else{
            if ([_device isFlashModeSupported:AVCaptureFlashModeOn]) {
                [_device setFlashMode:AVCaptureFlashModeOn];
                _isflashOn = YES;
                [_flashButton setTitle:@"闪光灯开" forState:UIControlStateNormal];
            }
        }
        
        [_device unlockForConfiguration];
    }
}

6.切换前后摄像头

- (void)changeCamera{
    //获取摄像头的数量
    NSUInteger cameraCount = [[AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo] count];
    //摄像头小于等于1的时候直接返回
    if (cameraCount <= 1) return;
    
    AVCaptureDevice *newCamera = nil;
    AVCaptureDeviceInput *newInput = nil;
    //获取当前相机的方向(前还是后)
    AVCaptureDevicePosition position = [[self.input device] position];
    
    //为摄像头的转换加转场动画
    CATransition *animation = [CATransition animation];
    animation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
    animation.duration = 0.5;
    animation.type = @"oglFlip";
    
    if (position == AVCaptureDevicePositionFront) {
        //获取后置摄像头
        newCamera = [self cameraWithPosition:AVCaptureDevicePositionBack];
        animation.subtype = kCATransitionFromLeft;
    }else{
        //获取前置摄像头
        newCamera = [self cameraWithPosition:AVCaptureDevicePositionFront];
        animation.subtype = kCATransitionFromRight;
    }
    
    [self.previewLayer addAnimation:animation forKey:nil];
    //输入流
    newInput = [AVCaptureDeviceInput deviceInputWithDevice:newCamera error:nil];
  
    
    if (newInput != nil) {
        
        [self.session beginConfiguration];
        //先移除原来的input
        [self.session removeInput:self.input];
        
        if ([self.session canAddInput:newInput]) {
            [self.session addInput:newInput];
            self.input = newInput;
            
        } else {
            //如果不能加现在的input,就加原来的input
            [self.session addInput:self.input];
        }
        
        [self.session commitConfiguration];
        
    }
    
    
}

- (AVCaptureDevice *)cameraWithPosition:(AVCaptureDevicePosition)position{
    NSArray *devices = [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo];
    for ( AVCaptureDevice *device in devices )
        if ( device.position == position ) return device;
    return nil;
}

7.拍照---保存

#pragma mark- 拍照
- (void)shutterCamera
{
    AVCaptureConnection * videoConnection = [self.ImageOutPut connectionWithMediaType:AVMediaTypeVideo];
    if (videoConnection ==  nil) {
        return;
    }
    
    [self.ImageOutPut captureStillImageAsynchronouslyFromConnection:videoConnection completionHandler:^(CMSampleBufferRef imageDataSampleBuffer, NSError *error) {
       
        if (imageDataSampleBuffer == nil) {
            return;
        }
        
        NSData *imageData =  [AVCaptureStillImageOutput jpegStillImageNSDataRepresentation:imageDataSampleBuffer];
        [self saveImageWithImage:[UIImage imageWithData:imageData]];
        
        
    }];
    
}
/**
 * 保存图片到相册
 */
- (void)saveImageWithImage:(UIImage *)image {
    // 判断授权状态
    [PHPhotoLibrary requestAuthorization:^(PHAuthorizationStatus status) {
        if (status != PHAuthorizationStatusAuthorized) return;
        
        dispatch_async(dispatch_get_main_queue(), ^{
            NSError *error = nil;
            
            // 保存相片到相机胶卷
            __block PHObjectPlaceholder *createdAsset = nil;
            [[PHPhotoLibrary sharedPhotoLibrary] performChangesAndWait:^{
                createdAsset = [PHAssetCreationRequest creationRequestForAssetFromImage:image].placeholderForCreatedAsset;
            } error:&error];
            
            if (error) {
                NSLog(@"保存失败:%@", error);
                return;
            }
        });
    }];
}

 

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