参考代码：
#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;
//
//}
//屏幕旋转时调整视频预览图层的方向
-(void)willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration{
AVCaptureConnection *captureConnection=[self.captureVideoPreviewLayer connection];
captureConnection.videoOrientation=(AVCaptureVideoOrientation)toInterfaceOrientation;
}
//旋转后重新设置大小
-(void)didRotateFromInterfaceOrientation:(UIInterfaceOrientation)fromInterfaceOrientation{
_captureVideoPreviewLayer.frame=self.viewContainer.bounds;
}
-(void)dealloc{
[self removeNotification];
}
#pragma mark - UI方法
#pragma mark 视频录制
- (void)takeButtonClick:(UIButton *)sender {
//根据设备输出获得连接
AVCaptureConnection *captureConnection=[self.captureMovieFileOutput connectionWithMediaType:AVMediaTypeVideo];
//根据连接取得设备输出的数据
if (![self.captureMovieFileOutput isRecording]) {
self.enableRotation=NO;
//如果支持多任务则则开始多任务
if ([[UIDevice currentDevice] isMultitaskingSupported]) {
self.backgroundTaskIdentifier=[[UIApplication sharedApplication] beginBackgroundTaskWithExpirationHandler:nil];
}
//预览图层和视频方向保持一致
captureConnection.videoOrientation=[self.captureVideoPreviewLayer connection].videoOrientation;
NSString *outputFielPath=[NSTemporaryDirectory() stringByAppendingString:@"myMovie.mov"];
NSLog(@"save path is :%@",outputFielPath);
NSURL *fileUrl=[NSURL fileURLWithPath:outputFielPath];
[self.captureMovieFileOutput startRecordingToOutputFileURL:fileUrl recordingDelegate:self];
}
else{
[self.captureMovieFileOutput stopRecording];//停止录制
}
}
#pragma mark 切换前后摄像头
- (void)toggleButtonClick:(UIButton *)sender {
AVCaptureDevice *currentDevice=[self.captureDeviceInput device];
AVCaptureDevicePosition currentPosition=[currentDevice position];
[self removeNotificationFromCaptureDevice:currentDevice];
AVCaptureDevice *toChangeDevice;
AVCaptureDevicePosition toChangePosition=AVCaptureDevicePositionFront;
if (currentPosition==AVCaptureDevicePositionUnspecified||currentPosition==AVCaptureDevicePositionFront) {
toChangePosition=AVCaptureDevicePositionBack;
}
toChangeDevice=[self getCameraDeviceWithPosition:toChangePosition];
[self addNotificationToCaptureDevice:toChangeDevice];
//获得要调整的设备输入对象
AVCaptureDeviceInput *toChangeDeviceInput=[[AVCaptureDeviceInput alloc]initWithDevice:toChangeDevice error:nil];
//改变会话的配置前一定要先开启配置，配置完成后提交配置改变
[self.captureSession beginConfiguration];
//移除原有输入对象
[self.captureSession removeInput:self.captureDeviceInput];
//添加新的输入对象
if ([self.captureSession canAddInput:toChangeDeviceInput]) {
[self.captureSession addInput:toChangeDeviceInput];
self.captureDeviceInput=toChangeDeviceInput;
}
//提交会话配置
[self.captureSession commitConfiguration];
}
#pragma mark - 视频输出代理
-(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(@"视频录制完成.");
//视频录入完成之后在后台将视频存储到相簿
self.enableRotation=YES;
UIBackgroundTaskIdentifier lastBackgroundTaskIdentifier=self.backgroundTaskIdentifier;
self.backgroundTaskIdentifier=UIBackgroundTaskInvalid;
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);
}
if (lastBackgroundTaskIdentifier!=UIBackgroundTaskInvalid) {
[[UIApplication sharedApplication] endBackgroundTask:lastBackgroundTaskIdentifier];
}
NSLog(@"成功保存视频到相簿.");
}];
}
#pragma mark - 通知
/**
* 给输入设备添加通知
*/
-(void)addNotificationToCaptureDevice:(AVCaptureDevice *)captureDevice{
//注意添加区域改变捕获通知必须首先设置设备允许捕获
[self changeDeviceProperty:^(AVCaptureDevice *captureDevice) {
captureDevice.subjectAreaChangeMonitoringEnabled=YES;
}];
NSNotificationCenter *notificationCenter= [NSNotificationCenter defaultCenter];
//捕获区域发生改变
[notificationCenter addObserver:self selector:@selector(areaChange:) name:AVCaptureDeviceSubjectAreaDidChangeNotification object:captureDevice];
}
-(void)removeNotificationFromCaptureDevice:(AVCaptureDevice *)captureDevice{
NSNotificationCenter *notificationCenter= [NSNotificationCenter defaultCenter];
[notificationCenter removeObserver:self name:AVCaptureDeviceSubjectAreaDidChangeNotification object:captureDevice];
}
/**
* 移除所有通知
*/
-(void)removeNotification{
NSNotificationCenter *notificationCenter= [NSNotificationCenter defaultCenter];
[notificationCenter removeObserver:self];
}
-(void)addNotificationToCaptureSession:(AVCaptureSession *)captureSession{
NSNotificationCenter *notificationCenter= [NSNotificationCenter defaultCenter];
//会话出错
[notificationCenter addObserver:self selector:@selector(sessionRuntimeError:) name:AVCaptureSessionRuntimeErrorNotification object:captureSession];
}
/**
* 设备连接成功
*
* @param notification 通知对象
*/
-(void)deviceConnected:(NSNotification *)notification{
NSLog(@"设备已连接...");
}
/**
* 设备连接断开
*
* @param notification 通知对象
*/
-(void)deviceDisconnected:(NSNotification *)notification{
NSLog(@"设备已断开.");
}
/**
* 捕获区域改变
*
* @param notification 通知对象
*/
-(void)areaChange:(NSNotification *)notification{
NSLog(@"捕获区域改变...");
}
/**
* 会话出错
*
* @param notification 通知对象
*/
-(void)sessionRuntimeError:(NSNotification *)notification{
NSLog(@"会话发生错误.");
}
#pragma mark - 私有方法
/**
* 取得指定位置的摄像头
*
* @param position 摄像头位置
*
* @return 摄像头设备
*/
-(AVCaptureDevice *)getCameraDeviceWithPosition:(AVCaptureDevicePosition )position{
NSArray *cameras= [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo];
for (AVCaptureDevice *camera in cameras) {
if ([camera position]==position) {
return camera;
}
}
return nil;
}
/**
* 改变设备属性的统一操作方法
*
* @param propertyChange 属性改变操作
*/
-(void)changeDeviceProperty:(PropertyChangeBlock)propertyChange{
AVCaptureDevice *captureDevice= [self.captureDeviceInput device];
NSError *error;
//注意改变设备属性前一定要首先调用lockForConfiguration:调用完之后使用unlockForConfiguration方法解锁
if ([captureDevice lockForConfiguration:&error]) {
propertyChange(captureDevice);
[captureDevice unlockForConfiguration];
}else{
NSLog(@"设置设备属性过程发生错误，错误信息：%@",error.localizedDescription);
}
}
/**
* 设置闪光灯模式
*
* @param flashMode 闪光灯模式
*/
-(void)setFlashMode:(AVCaptureFlashMode )flashMode{
[self changeDeviceProperty:^(AVCaptureDevice *captureDevice) {
if ([captureDevice isFlashModeSupported:flashMode]) {
[captureDevice setFlashMode:flashMode];
}
}];
}
/**
* 设置聚焦模式
*
* @param focusMode 聚焦模式
*/
-(void)setFocusMode:(AVCaptureFocusMode )focusMode{
[self changeDeviceProperty:^(AVCaptureDevice *captureDevice) {
if ([captureDevice isFocusModeSupported:focusMode]) {
[captureDevice setFocusMode:focusMode];
}
}];
}
/**
* 设置曝光模式
*
* @param exposureMode 曝光模式
*/
-(void)setExposureMode:(AVCaptureExposureMode)exposureMode{
[self changeDeviceProperty:^(AVCaptureDevice *captureDevice) {
if ([captureDevice isExposureModeSupported:exposureMode]) {
[captureDevice setExposureMode:exposureMode];
}
}];
}
/**
* 设置聚焦点
*
* @param point 聚焦点
*/
-(void)focusWithMode:(AVCaptureFocusMode)focusMode exposureMode:(AVCaptureExposureMode)exposureMode atPoint:(CGPoint)point{
[self changeDeviceProperty:^(AVCaptureDevice *captureDevice) {
if ([captureDevice isFocusModeSupported:focusMode]) {
[captureDevice setFocusMode:AVCaptureFocusModeAutoFocus];
}
if ([captureDevice isFocusPointOfInterestSupported]) {
[captureDevice setFocusPointOfInterest:point];
}
if ([captureDevice isExposureModeSupported:exposureMode]) {
[captureDevice setExposureMode:AVCaptureExposureModeAutoExpose];
}
if ([captureDevice isExposurePointOfInterestSupported]) {
[captureDevice setExposurePointOfInterest:point];
}
}];
}
/**
* 添加点按手势，点按时聚焦
*/
-(void)addGenstureRecognizer{
UITapGestureRecognizer *tapGesture=[[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(tapScreen:)];
[self.viewContainer addGestureRecognizer:tapGesture];
}
-(void)tapScreen:(UITapGestureRecognizer *)tapGesture{
CGPoint point= [tapGesture locationInView:self.viewContainer];
//将UI坐标转化为摄像头坐标
CGPoint cameraPoint= [self.captureVideoPreviewLayer captureDevicePointOfInterestForPoint:point];
[self setFocusCursorWithPoint:point];
[self focusWithMode:AVCaptureFocusModeAutoFocus exposureMode:AVCaptureExposureModeAutoExpose atPoint:cameraPoint];
}
/**
* 设置聚焦光标位置
*
* @param point 光标位置
*/
-(void)setFocusCursorWithPoint:(CGPoint)point{
self.focusCursor.center=point;
self.focusCursor.transform=CGAffineTransformMakeScale(1.5, 1.5);
self.focusCursor.alpha=1.0;
[UIView animateWithDuration:1.0 animations:^{
self.focusCursor.transform=CGAffineTransformIdentity;
} completion:^(BOOL finished) {
self.focusCursor.alpha=0;
}];
}
@end
