一.原生二维码扫描
AVCaptureSession
管理输入(AVCaptureInput)和输出(AVCaptureOutput)流，包含开启和停止会话方法。
AVCaptureDeviceInput
是AVCaptureInput的子类,可以作为输入捕获会话，用AVCaptureDevice实例初始化。
AVCaptureDevice
代表了物理捕获设备如:摄像机。用于配置等底层硬件设置相机的自动对焦模式。
AVCaptureMetadataOutput
是AVCaptureOutput的子类，处理输出捕获会话。捕获的对象传递给一个委托实现AVCaptureMetadataOutputObjectsDelegate协议。协议方法在指定的派发队列（dispatch queue）上执行。
AVCaptureVideoPreviewLayer
CALayer的一个子类，显示捕获到的相机输出流。
1.遵守协议
引入 ：
#import <AVFoundation/AVFoundation.h>
<AVCaptureMetadataOutputObjectsDelegate>
2.声明属性
{
AVCaptureSession * session;//输入输出的中间桥梁
}
3.在viewdidload中加入下面的方法
//获取摄像设备
AVCaptureDevice * device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
//创建输入流
AVCaptureDeviceInput * input = [AVCaptureDeviceInput deviceInputWithDevice:device error:nil];
//创建输出流
AVCaptureMetadataOutput * output = [[AVCaptureMetadataOutput alloc]init];
//设置代理 在主线程里刷新
[output setMetadataObjectsDelegate:self queue:dispatch_get_main_queue()];
//初始化链接对象
session = [[AVCaptureSession alloc]init];
//高质量采集率
[session setSessionPreset:AVCaptureSessionPresetHigh];
[session addInput:input];
[session addOutput:output];
//设置扫码支持的编码格式(如下设置条形码和二维码兼容)
output.metadataObjectTypes=@[AVMetadataObjectTypeQRCode,AVMetadataObjectTypeEAN13Code, AVMetadataObjectTypeEAN8Code, AVMetadataObjectTypeCode128Code];
AVCaptureVideoPreviewLayer * layer = [AVCaptureVideoPreviewLayer layerWithSession:session];
layer.videoGravity=AVLayerVideoGravityResizeAspectFill;
layer.frame=self.view.layer.bounds;
[self.view.layer insertSublayer:layer atIndex:0];
//开始捕获
[session startRunning];
实现完成二维码条形码的扫描
-(void)captureOutput:(AVCaptureOutput *)captureOutput didOutputMetadataObjects:(NSArray *)metadataObjects fromConnection: (AVCaptureConnection *)connection{
if (metadataObjects.count>0) {
//[session stopRunning];
AVMetadataMachineReadableCodeObject * metadataObject = [metadataObjects objectAtIndex : 0 ];
//输出扫描字符串
NSLog(@"%@",metadataObject.stringValue);
}
}
三.从相册选择二维码进行扫描
UIImagePickerController *picker = [[UIImagePickerController alloc] init];
picker.delegate = self;
picker.allowsEditing = true;
[self presentViewController:picker animated:true completion:nil];
遵守代理
UINavigationControllerDelegate, UIImagePickerControllerDelegate
执行代理方法
pragma mark - UIImagePickerControllerDelegate
-
(void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary<NSString *,id> *)info {
[picker dismissViewControllerAnimated:true completion:^{
UIImage *image = info[UIImagePickerControllerEditedImage];
if (!image) {
image = info[UIImagePickerControllerOriginalImage];
}
NSData *imageData = UIImageJPEGRepresentation(image, 1);
// kCIContextUseSoftwareRenderer : 软件渲染 -- 可以消除 "BSXPCMessage received error for message: Connection interrupted" 警告
// kCIContextPriorityRequestLow : 低优先级在 GPU 渲染-- 设置为false可以加快图片处理速度
CIContext *context = [CIContext contextWithOptions:@{kCIContextUseSoftwareRenderer : @(true), kCIContextPriorityRequestLow : @(false)}];CIDetector *detector = [CIDetector detectorOfType:CIDetectorTypeQRCode context:context options:nil]; CIImage *ciImage = [CIImage imageWithData:imageData]; NSArray *ar = [detector featuresInImage:ciImage]; CIQRCodeFeature *feature = [ar firstObject]; NSLog(@"detector: %@", detector); NSLog(@"context: %@", feature.messageString); UIAlertController *alert = [UIAlertController alertControllerWithTitle:nil message:[NSString stringWithFormat:@"扫描结果：%@", feature.messageString ?: @"空"] preferredStyle:UIAlertControllerStyleAlert]; [alert addAction:[UIAlertAction actionWithTitle:@"Sure" style:UIAlertActionStyleCancel handler:nil]]; [self presentViewController:alert animated:true completion:nil]; }]; } - (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker { [picker dismissViewControllerAnimated:true completion:nil]; }
经过测试CIDetector 这个方法必须在5s以上的设备才可以使用
