利用AVFoundation实现Blink拍照和录像的功能详解手机开发

前几天偶然发现一个app叫Blink,闲来无事,纯当练手,于是就尝试下自己实现它的功能.

页面都挺简单的

– (void)openCamera:(AVCaptureDevicePosition)cameraPostion {

    BOOL hasCamera = ([[AVCaptureDevice devices] count] > );

    if (hasCamera) {

        AVCaptureSession *session = [[AVCaptureSession alloc] init];

        session.sessionPreset = AVCaptureSessionPresetHigh;

       

        AVCaptureVideoPreviewLayer *captureVideoPreviewLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:session];

        [captureVideoPreviewLayer setVideoGravity:AVLayerVideoGravityResizeAspectFill];

        [captureVideoPreviewLayer setFrame:self.cameraImageView.bounds];

        [self.cameraImageView.layer addSublayer:captureVideoPreviewLayer];

       

        AVCaptureDevice *device = [self getCamera:cameraPostion];

        NSError *error = nil;

       

        AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:device error:&error];

        [session addInput:input];

       

        stillImageOutput = [[AVCaptureStillImageOutput alloc] init];

        NSDictionary *outputSettings = @{ AVVideoCodecKey : AVVideoCodecJPEG};

        [stillImageOutput setOutputSettings:outputSettings];

        [session addOutput:stillImageOutput];

       

        movieOutput = [[AVCaptureMovieFileOutput alloc] init];

        [session addOutput:movieOutput];

       

        [session startRunning];

    }

}

– (AVCaptureDevice *)getCamera:(AVCaptureDevicePosition)cameraPostion {

    NSArray *cameras = [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo];

    for (AVCaptureDevice *device in cameras) {

        if (device.position == cameraPostion)

            return device;

    }

    return [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];

}

– (void)captureNow {

    AVCaptureConnection *videoConnection = nil;

    for (AVCaptureConnection *connection in stillImageOutput.connections) {

        for (AVCaptureInputPort *port in [connection inputPorts]) {

            if ([[port mediaType] isEqual:AVMediaTypeVideo] ) {

                videoConnection = connection;

                break;

            }

        }

        if (videoConnection) { break; }

    }

    // 取静态图片

    [stillImageOutput captureStillImageAsynchronouslyFromConnection:videoConnection

              completionHandler: ^(CMSampleBufferRef imageSampleBuffer, NSError *error) {

                  NSData *imageData = [AVCaptureStillImageOutput jpegStillImageNSDataRepresentation:imageSampleBuffer];

                  NSData *compressedData = [imageData gzippedDataWithCompressionLevel:1.0];

                  NSData *outputData = [compressedData gunzippedData];

                  UIImage *imageT = [[UIImage alloc] initWithData:outputData];

                  _testImageView.image = imageT;

                  _testImageView.hidden = NO;

                  NSFileManager *fileManager = [NSFileManager defaultManager];

                  NSString *filePath = [[NSString alloc] initWithFormat:@”%@%@”, NSTemporaryDirectory(),@”main.png”];

                  [fileManager createFileAtPath:filePath contents:imageData attributes:nil];

                 

                  NSString *zipFile = [[NSString alloc] initWithFormat:@”%@%@”, NSTemporaryDirectory(),@”main.zip”];

                  ZipArchive *za = [[ZipArchive alloc] init];

                  [za CreateZipFile2:zipFile];

                  [za addFileToZip:filePath newname:@”main.png”];

              }];

}

– (IBAction)beginRecord:(id)sender {

    [movieOutput startRecordingToOutputFileURL:[self fileURLWithName:@”main.mp4″] recordingDelegate:self];

}

– (void)stopRecord {

    [movieOutput stopRecording];

}

– (void)captureOutput:(AVCaptureFileOutput *)captureOutput

        didFinishRecordingToOutputFileAtURL:(NSURL *)outputFileURL

              fromConnections:(NSArray *)connections

                        error:(NSError *)error {

    BOOL recordedSuccessfully = YES;

    if (error == nil) {

        [self playVideo:outputFileURL];

    }

    if ([error code] != noErr) {

        id value = [[error userInfo] objectForKey:AVErrorRecordingSuccessfullyFinishedKey];

        if (value) {

            recordedSuccessfully = [value boolValue];

           

        }

    }

}

– (void)playVideo:(NSURL *)url {

    AVPlayer *player = [AVPlayer playerWithURL:url];

    playerLayer = [AVPlayerLayer playerLayerWithPlayer:player];

   

    playerLayer.frame = CGRectMake(, , 160, 284);

    playerLayer.position = self.view.center;

    [self.view.layer addSublayer:playerLayer];

   

    playerLayer.masksToBounds = YES;

    playerLayer.cornerRadius = 20;

    playerLayer.borderWidth = 1;

    playerLayer.borderColor = [UIColor grayColor].CGColor;

   

    [player play];

    [[NSNotificationCenter defaultCenter]

                         addObserver:self

                         selector:@selector(removePlayer)

                         name:AVPlayerItemDidPlayToEndTimeNotification

                         object:nil];

}

– (void)removePlayer {

    [playerLayer removeFromSuperlayer];

}

看了下它的网络数据格式方面,Blink主要是打包成zip文件,里面包含json,mp4,png文件.

等有空了,把服务器也写一下,或者谁有兴趣可以把它的服务器实现下.

当然Blink还有一些添加好友,分享等的功能,这些细节还是比较好实现的.