iOS 仿微信录制小视频

Demo 地址
JCVideoRecord

最近有个需求涉及到录制一个小视频上传服务器，所以写了这个Demo，在这记录下，供学习用，主要使用的是AVFoundation 框架。

IMB_AX2vxc.GIF

使用

- (void)present{
    _recordView = [[JCVideoRecordView alloc]initWithFrame:[UIScreen mainScreen].bounds];
    _recordView.cancelBlock = ^{

    };
    _recordView.completionBlock = ^(NSURL *fileUrl) {
        
    };
    [_recordView present];
}

简单介绍

1.目录结构

屏幕快照 2017-09-29 下午1.29.07.png

2. 流程

创建JCVideoRecordView时，初始化JCVideoRecordManager, JCVideoRecordManager负责管理视频采集，录制，压缩等操作，录制结束后创建JCRecordPlayerView 来循环播放录制的视频，点击确定回调给VCL。

$ 主要代码

JCVideoRecordManager.h

@protocol JCVideoRecordManagerDelegate 
//录制结束
- (void)captureOutput:(AVCaptureFileOutput *)captureOutput didFinishRecordingToOutputFileAtURL:(NSURL *)outputFileURL fromConnections:(NSArray *)connections error:(NSError *)error;

//录制时间
- (void)recordTimeCurrentTime:(CGFloat)currentTime totalTime:(CGFloat)totalTime;
@end

@interface JCVideoRecordManager : NSObject
@property (nonatomic, weak) id delegate;
//摄像头视图层
@property (nonatomic, strong) AVCaptureVideoPreviewLayer *preViewLayer;

// 准备录制
- (void)prepareForRecord;

// 开始录制
- (void)startRecordToFile:(NSURL *)outPutFile;

// 停止录制
- (void)stopCurrentVideoRecording;

// 切换摄像头
- (void)switchCamera;

// 设置对焦
- (void)setFoucusWithPoint:(CGPoint)point;

//压缩视频
- (void)compressVideo:(NSURL *)inputFileURL complete:(void(^)(BOOL success, NSURL* outputUrl))complete;

JCVideoRecordManager.m

- (instancetype)init{
    self = [super init];
    if (self) {
        self.captureSession = [[AVCaptureSession alloc]init];
        self.movieFileOutput = [[AVCaptureMovieFileOutput alloc]init];
        //后台播放音频时需要注意加以下代码，否则会获取音频设备失败
        [[AVAudioSession sharedInstance] setCategory:AVAudioSessionCategoryPlayAndRecord error:nil];
        [[AVAudioSession sharedInstance] setMode:AVAudioSessionModeVideoRecording error:nil];
        [[AVAudioSession sharedInstance] setActive:YES withOptions:AVAudioSessionSetActiveOptionNotifyOthersOnDeactivation error:nil];
        [self prepareForRecord];
    }
    return self;
}

#pragma mark - 获取权限
+ (void)getCameraAuth:(void(^)(BOOL boolValue, NSString *tipText))isAuthorized{
    __weak typeof(self) instance = self;
    //获取视频权限
    AVAuthorizationStatus authStatus = [AVCaptureDevice authorizationStatusForMediaType:AVMediaTypeVideo];
    if (authStatus == AVAuthorizationStatusNotDetermined){
        [AVCaptureDevice requestAccessForMediaType:AVMediaTypeVideo
                                 completionHandler:^(BOOL granted) {
                                     if (granted) {
                                         [instance getCameraAuth:isAuthorized];
                                     }else{
                                         isAuthorized(NO, @"没有获得相机权限");
                                     }
                                 }];
    }else if (authStatus == AVAuthorizationStatusAuthorized){
        [[AVAudioSession sharedInstance] requestRecordPermission:^(BOOL granted) {
            isAuthorized(granted,  @"没有获得麦克风权限");
        }];
    }else{
        isAuthorized(NO, @"没有获得相机权限");
    }
}

#pragma mark - 摄像头视图层
- (AVCaptureVideoPreviewLayer *)preViewLayer{
    if (!_preViewLayer) {
        _preViewLayer = [AVCaptureVideoPreviewLayer layerWithSession:self.captureSession];
        _preViewLayer.masksToBounds = YES;
        _preViewLayer.videoGravity = AVLayerVideoGravityResizeAspectFill;
    }
    return _preViewLayer;
}

#pragma mark 视频输入
- (AVCaptureDeviceInput *)mediaDeviceInput{
    if (!_mediaDeviceInput) {
        __block AVCaptureDevice *backCamera  = nil;
        NSArray *cameras = [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo];
        [cameras enumerateObjectsUsingBlock:^(AVCaptureDevice *camera, NSUInteger idx, BOOL * _Nonnull stop) {
            if(camera.position == AVCaptureDevicePositionBack){
                backCamera = camera;
            }
        }];
        [self setExposureModeWithDevice:backCamera];
        _mediaDeviceInput = [AVCaptureDeviceInput deviceInputWithDevice:backCamera error:nil];
    }
    return _mediaDeviceInput;
}

#pragma mark 音频输入
- (AVCaptureDeviceInput *)audioDeviceInput{
    if (!_audioDeviceInput) {
        NSError *error;
        _audioDeviceInput = [AVCaptureDeviceInput deviceInputWithDevice:[AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeAudio] error:&error];
    }
    return _audioDeviceInput;
}

#pragma mark - 输入输出对象连接
- (AVCaptureConnection *)captureConnection{
    return _captureConnection = _captureConnection ? : [self.movieFileOutput connectionWithMediaType:AVMediaTypeVideo];
}

#pragma mark 配置曝光模式 设置持续曝光模式
- (void)setExposureModeWithDevice:(AVCaptureDevice *)device{
    //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
    NSError *error = nil;
    [device lockForConfiguration:&error];
    if ([device isExposureModeSupported:AVCaptureExposureModeContinuousAutoExposure]){
        [device setExposureMode:AVCaptureExposureModeContinuousAutoExposure];
    }
    [device unlockForConfiguration];
}

#pragma mark 计时器相关
- (NSTimer *)timer{
    if (!_timer){
        _timer = [NSTimer scheduledTimerWithTimeInterval:KTimerInterval target:self selector:@selector(fire:) userInfo:nil repeats:YES];
    }
    return _timer;
}

- (void)fire:(NSTimer *)timer{
    self.recordTime += KTimerInterval;
    if ([self.delegate respondsToSelector:@selector(recordTimeCurrentTime:totalTime:)]) {
        [self.delegate recordTimeCurrentTime:self.recordTime totalTime:KMaxRecordTime];
    }
    if(_recordTime >= KMaxRecordTime){
        [self stopCurrentVideoRecording];
    }
}

- (void)startTimer{
    [self.timer invalidate];
    self.timer = nil;
    self.recordTime = 0;
    [self.timer fire];
}

- (void)stopTimer{
    [self.timer invalidate];
    self.timer = nil;
}

#pragma mark 准备录制
- (void)prepareForRecord{
    [self.captureSession beginConfiguration];
    
    //视频采集质量
    [self.captureSession canSetSessionPreset:AVCaptureSessionPresetHigh] ? [self.captureSession setSessionPreset:AVCaptureSessionPresetHigh] : nil;
    
    //添加input
    [self.captureSession canAddInput:self.mediaDeviceInput] ? [self.captureSession addInput:self.mediaDeviceInput] : nil;
    [self.captureSession canAddInput:self.audioDeviceInput] ? [self.captureSession addInput:self.audioDeviceInput] : nil;
    
    //添加output
    [self.captureSession canAddOutput:self.movieFileOutput] ? [self.captureSession addOutput:self.movieFileOutput] : nil;

    [self.captureSession commitConfiguration];
    
    // 防抖功能
    if ([self.captureConnection isVideoStabilizationSupported] && self.captureConnection.activeVideoStabilizationMode == AVCaptureVideoStabilizationModeOff){
        self.captureConnection.preferredVideoStabilizationMode = AVCaptureVideoStabilizationModeAuto;
    }
    
    [self.captureSession startRunning];
}

#pragma mark 切换摄像头
- (void)switchCamera{
    [_captureSession beginConfiguration];
    [_captureSession removeInput:_mediaDeviceInput];
    AVCaptureDevice *swithToDevice = [self switchCameraDevice];
    [swithToDevice lockForConfiguration:nil];
    [self setExposureModeWithDevice:swithToDevice];
    self.mediaDeviceInput = [AVCaptureDeviceInput deviceInputWithDevice:swithToDevice error:nil];
    [_captureSession addInput:_mediaDeviceInput];
    [_captureSession commitConfiguration];
}

#pragma mark 获取切换时的摄像头
- (AVCaptureDevice *)switchCameraDevice{
    AVCaptureDevice *currentDevice = [self.mediaDeviceInput device];
    AVCaptureDevicePosition currentPosition = [currentDevice position];
    BOOL isUnspecifiedOrFront = (currentPosition == AVCaptureDevicePositionUnspecified || currentPosition ==AVCaptureDevicePositionFront );
    AVCaptureDevicePosition swithToPosition = isUnspecifiedOrFront ? AVCaptureDevicePositionBack:AVCaptureDevicePositionFront;
    NSArray *cameras = [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo];
    __block AVCaptureDevice *swithCameraDevice = nil;
    [cameras enumerateObjectsUsingBlock:^(AVCaptureDevice *camera, NSUInteger idx, BOOL * _Nonnull stop) {
        if (camera.position == swithToPosition){
            swithCameraDevice = camera;
            *stop = YES;
        };
    }];
    return swithCameraDevice;
}

#pragma mark 开始录制
- (void)startRecordToFile:(NSURL *)outPutFile{
    
    if (!self.captureConnection) {
        return;
    }
    
    if ([self.movieFileOutput isRecording]) {
        return;
    }
    if ([self.captureConnection isVideoOrientationSupported]){
        self.captureConnection.videoOrientation =[self.preViewLayer connection].videoOrientation;
    }
    [_movieFileOutput startRecordingToOutputFileURL:outPutFile recordingDelegate:self];
}

#pragma mark  停止录制
- (void)stopCurrentVideoRecording{
    if (self.movieFileOutput.isRecording) {
        [self stopTimer];
        [_movieFileOutput stopRecording];
    }
}

#pragma mark 设置对焦
- (void)setFoucusWithPoint:(CGPoint)point{
    CGPoint cameraPoint= [self.preViewLayer captureDevicePointOfInterestForPoint:point];
    [self focusWithMode:AVCaptureFocusModeContinuousAutoFocus exposureMode:AVCaptureExposureModeContinuousAutoExposure atPoint:cameraPoint];
}

-(void)focusWithMode:(AVCaptureFocusMode)focusMode exposureMode:(AVCaptureExposureMode)exposureMode atPoint:(CGPoint)point{
    [self changeDeviceProperty:^(AVCaptureDevice *captureDevice) {
        
        if ([captureDevice isFocusModeSupported:focusMode]) {
            [captureDevice setFocusMode:focusMode];
        }
       
        if ([captureDevice isFocusPointOfInterestSupported]) {
            [captureDevice setFocusPointOfInterest:point];
        }
        
        if ([captureDevice isExposureModeSupported:exposureMode]) {
            [captureDevice setExposureMode:exposureMode];
        }
       
        if ([captureDevice isExposurePointOfInterestSupported]) {
            [captureDevice setExposurePointOfInterest:point];
        }
    }];
}
#pragma mark - 改变设备属性方法
- (void)changeDeviceProperty:(void (^)(id obj))propertyChange
{
    AVCaptureDevice *captureDevice = [self.mediaDeviceInput device];
    NSError *error;
    
    if ([captureDevice lockForConfiguration:&error]) {
        propertyChange(captureDevice);
        [captureDevice unlockForConfiguration];
    }else{
        
    }
}

#pragma mark - AVCaptureFileOutputRecordignDelegate method

// 录制开始
- (void)captureOutput:(AVCaptureFileOutput *)captureOutput didStartRecordingToOutputFileAtURL:(NSURL *)fileURL fromConnections:(NSArray *)connections{
    [self startTimer];
}

// 录制结束
-(void)captureOutput:(AVCaptureFileOutput *)captureOutput didFinishRecordingToOutputFileAtURL:(NSURL *)outputFileURL fromConnections:(NSArray *)connections error:(NSError *)error{
    [self stopTimer];
    if (self.delegate && [self.delegate respondsToSelector:@selector(captureOutput:didFinishRecordingToOutputFileAtURL:fromConnections:error:)]) {
        [self.delegate captureOutput:captureOutput didFinishRecordingToOutputFileAtURL:outputFileURL fromConnections:connections error:error];
    }
    [self.captureSession stopRunning];
}

#pragma mark - 压缩视频
- (void)compressVideo:(NSURL *)inputFileURL complete:(void(^)(BOOL success, NSURL* outputUrl))complete{
    NSURL *outPutUrl = [NSURL fileURLWithPath:[JCVideoRecordManager cacheFilePath:NO]];
    [self convertVideoQuailtyWithInputURL:inputFileURL outputURL:outPutUrl completeHandler:^(AVAssetExportSession *exportSession) {
        complete(exportSession.status == AVAssetExportSessionStatusCompleted, outPutUrl);
    }];
}

- (void)convertVideoQuailtyWithInputURL:(NSURL*)inputURL
                               outputURL:(NSURL*)outputURL
                         completeHandler:(void (^)(AVAssetExportSession*))handler{
    AVURLAsset *avAsset = [AVURLAsset URLAssetWithURL:inputURL options:nil];
    
    AVAssetExportSession *exportSession = [[AVAssetExportSession alloc] initWithAsset:avAsset presetName:AVAssetExportPresetMediumQuality];
    
    exportSession.outputURL = outputURL;
    exportSession.outputFileType = AVFileTypeMPEG4;
    exportSession.shouldOptimizeForNetworkUse= YES;
    [exportSession exportAsynchronouslyWithCompletionHandler:^(void){
         handler(exportSession);
    }];
}

写在最后

demo还有很多需要完善的地方，例如视频剪裁，设备方向，闪光灯等，日后有时间继续完善。

Demo 地址
JCVideoRecord

参考

ios视频录制