iOS：GPUImage滤镜+采集

使用GPUImage进行采集摄像头数据，并且能够实现大部分的美颜效果 并且集成了闪光灯 摄像头切换 焦点缩放 聚焦功能
GIF演示

主要几个核心类：
GPUImageVideoCamera：封装系统的AVCaptureSession，AVCaptureDevice，AVCaptureDeviceInput，AVCaptureVideoDataOutput
演示

-(CCGPUImageVideoCamera *)videoCamera{
    if (!_videoCamera) {
        _videoCamera = [[CCGPUImageVideoCamera alloc] initWithSessionPreset:AVCaptureSessionPreset1280x720 cameraPosition:AVCaptureDevicePositionFront];
        _videoCamera.delegate = self;
        _videoCamera.audioDelegate = self;
        _videoCamera.outputImageOrientation = UIInterfaceOrientationPortrait;
        _videoCamera.horizontallyMirrorFrontFacingCamera = YES;// 前置摄像头需要 镜像反转
        _videoCamera.horizontallyMirrorRearFacingCamera = NO;// 后置摄像头不需要 镜像反转
        [_videoCamera addAudioInputsAndOutputs];//避免录制第一帧黑屏闪屏
        if ([_videoCamera.inputCamera lockForConfiguration:nil]) {
            //自动对焦
            if ([_videoCamera.inputCamera isFocusModeSupported:AVCaptureFocusModeContinuousAutoFocus]) {
                [_videoCamera.inputCamera setFocusMode:AVCaptureFocusModeContinuousAutoFocus];
            }
            //自动曝光
            if ([_videoCamera.inputCamera isExposureModeSupported:AVCaptureExposureModeContinuousAutoExposure]) {
                [_videoCamera.inputCamera setExposureMode:AVCaptureExposureModeContinuousAutoExposure];
            }
            //自动白平衡
            if ([_videoCamera.inputCamera isWhiteBalanceModeSupported:AVCaptureWhiteBalanceModeContinuousAutoWhiteBalance]) {
                [_videoCamera.inputCamera setWhiteBalanceMode:AVCaptureWhiteBalanceModeContinuousAutoWhiteBalance];
            }
            [_videoCamera.inputCamera unlockForConfiguration];
        }
        
    }
    return _videoCamera;
}

GPUImageView：获取采集到的数据进行展示
GPUImageMovieWriter：采集的视频 音频数据进行写入
GPUImageFilter：滤镜核心类

github：https://github.com/qw9685/GPUImage-