导入相机的API在AVFoundation里所以得包含头文件#import <AVFoundation/AVFoundation.h>
1.自定义相机需要的属性
@interface CustomCameraVC ()<UIAlertViewDelegate>//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)AVCaptureStillImageOutput *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];self.ImageOutPut = [[AVCaptureStillImageOutput alloc]init];//生成会话，用来结合输入输出self.session = [[AVCaptureSession alloc]init];if ([self.session canSetSessionPreset:AVCaptureSessionPreset1280x720]) {[self.session setSessionPreset:AVCaptureSessionPreset1280x720];}if ([self.session canAddInput:self.input]) {[self.session addInput:self.input];}if ([self.session canAddOutput:self.ImageOutPut]) {[self.session addOutput:self.ImageOutPut];}//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]) {//闪光灯自动if ([self.device isFlashModeSupported:AVCaptureFlashModeAuto]) {[self.device setFlashMode:AVCaptureFlashModeAuto];}//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;}});}];
}