使用OpenGLES和Swift进行照片预览iPhone

Question

我在Swift中使用OpenGLES进行照片预览而不是使用图层，因为我想在输出上放置滤镜。我正在使用我在objc.io objc.io camera capture tutorial

上找到的代码

我收到此错误 -

  

BSXPCMessage收到错误消息：连接中断

并且预览不会运行 - 空白屏幕

代码如下

import UIKit
import AVFoundation
import GLKit
import OpenGLES

class ViewController: UIViewController, AVCaptureVideoDataOutputSampleBufferDelegate {

let captureSession = AVCaptureSession()

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.
    var captureDevice : AVCaptureDevice?
    let devices = AVCaptureDevice.devices()


    for device in devices {

        if (device.hasMediaType(AVMediaTypeVideo)) {

            if(device.position == AVCaptureDevicePosition.Front) {
                captureDevice = device as? AVCaptureDevice
            }
        }
    }


    var err : NSError? = nil
    captureSession.addInput(AVCaptureDeviceInput(device: captureDevice, error: &err))

    if err != nil {
        println("error: \(err?.localizedDescription)")
    }


    captureSession.sessionPreset = AVCaptureSessionPresetPhoto


    captureSession.startRunning()

    let videoOutput : AVCaptureVideoDataOutput = AVCaptureVideoDataOutput()
    videoOutput.setSampleBufferDelegate(self, queue: dispatch_queue_create("sample buffer delegate", DISPATCH_QUEUE_SERIAL))

    if captureSession.canAddOutput(videoOutput) {
        captureSession.addOutput(videoOutput)
    }



}

func captureOutput(captureOutput: AVCaptureOutput!, didOutputSampleBuffer sampleBuffer: CMSampleBuffer!, fromConnection connection: AVCaptureConnection!) {

    let viewFrame : CGRect = self.view.frame

    let glContext = EAGLContext(API: .OpenGLES2)

    let glView = GLKView(frame: viewFrame, context: glContext)


    let ciContext = CIContext(EAGLContext: glContext)
    let pixelBuffer = CMSampleBufferGetImageBuffer(sampleBuffer)
    let image = CIImage(CVPixelBuffer: pixelBuffer)
    if glContext != EAGLContext.currentContext() {
        EAGLContext.setCurrentContext(glContext)
    }
    glView.bindDrawable()
    ciContext.drawImage(image, inRect:image.extent(), fromRect: image.extent())
    glView.display()
}