[swift学习之十三]二维码扫描练习

桃扇骨 2022-08-22 11:29 189阅读 0赞

<span style="color:#660000;">import UIKit
    import AVFoundation
    
    extension CGFloat{
        func ToInt() -> Int {
            return Int(self)
        }
    }
    
    extension CIImage{
        func ToUiImag(ASize: CGFloat) -> UIImage {
            let extent = CGRectIntegral(self.extent)
            let scale = min(ASize/CGRectGetWidth(extent), ASize/CGRectGetHeight(extent))
            let W = (CGRectGetWidth(extent) * scale).ToInt()
            let H = (CGRectGetHeight(extent) * scale).ToInt()
            let cs = CGColorSpaceCreateDeviceGray()
            let bitMapRef = CGBitmapContextCreate(nil, W, H, 8, 0, cs,0)
            let context = CIContext(options: nil)
            let bitMapImage = context.createCGImage(self, fromRect: extent)
            CGContextSetInterpolationQuality(bitMapRef, .None)
            CGContextScaleCTM(bitMapRef, scale, scale)
            CGContextDrawImage(bitMapRef, extent, bitMapImage)
            
            let scaledImag = CGBitmapContextCreateImage(bitMapRef)
            return UIImage(CGImage: scaledImag!)
        }
    }
    
    class ViewController: UIViewController, AVCaptureMetadataOutputObjectsDelegate{
        var session :AVCaptureSession!
        func captureOutput(captureOutput: AVCaptureOutput!, didOutputMetadataObjects metadataObjects: [AnyObject]!, fromConnection connection: AVCaptureConnection!) {
            if metadataObjects.count > 0 {
                let obj = metadataObjects.last
                let label = self.view.viewWithTag(3) as? UILabel
                label?.text = obj?.stringValue
                session.stopRunning()
                let AVimgView = self.view.viewWithTag(2) as? UIImageView
                AVimgView?.layer.sublayers?.removeAll()
            }
        }
        override func viewDidLoad() {
            super.viewDidLoad()
            let filter = CIFilter(name: "CIQRCodeGenerator")
            filter?.setDefaults()
            let str = "我是小宝贝，从不怕累，虽然功课一大堆。像个小baby，最爱馋嘴，还要吃奶嘴，哈哈"
            let data = str.dataUsingEncoding(NSUTF8StringEncoding)
            filter?.setValue(data, forKey: "inputMessage")
            let img = filter?.outputImage
            let imgView = self.view.viewWithTag(1) as? UIImageView
            imgView?.image = img?.ToUiImag((imgView?.frame.width)!)
            
    
            let device = AVCaptureDevice.defaultDeviceWithMediaType(AVMediaTypeVideo)
            do{
                let input = try AVCaptureDeviceInput(device: device)
                session = AVCaptureSession()
                session.sessionPreset = AVCaptureSessionPresetHigh
                session.addInput(input)
                let outPut = AVCaptureMetadataOutput();
                outPut.setMetadataObjectsDelegate(self, queue: dispatch_get_main_queue())
                session.addOutput(outPut)
                var types = [String]()
                types.append(AVMetadataObjectTypeQRCode)
                types.append(AVMetadataObjectTypeEAN13Code)
                types.append(AVMetadataObjectTypeEAN8Code)
                types.append(AVMetadataObjectTypeCode128Code)
                outPut.metadataObjectTypes =  types
                let avLayer = AVCaptureVideoPreviewLayer(session: session)
                let AVimgView = self.view.viewWithTag(2) as? UIImageView
                //outPut.rectOfInterest=CGRectMake(0.5,0,0.5, 1)
                avLayer.frame = (AVimgView?.bounds)!
                avLayer.videoGravity = AVLayerVideoGravityResizeAspectFill
                AVimgView?.layer.insertSublayer(avLayer, atIndex: 0)
                session.startRunning()
            }
            catch let e as NSError {
                print(e)
            }
            // Do any additional setup after loading the view, typically from a nib.
        }
        override func didReceiveMemoryWarning() {
            super.didReceiveMemoryWarning()
            // Dispose of any resources that can be recreated.
        }
    
    }
    </span>

1，头一回用到do..try..catch.

2，rectofInterest这个还没有弄明白

3，比较头疼的问题是，自己生成的不能扫，其他地方的却可以，包括条形码，不清楚原因。

4，没有加波纹，先这样吧。