iOS二维码的生成和扫描

2020-01-18 21:09:05于海丽

本文实例为大家分享了Android九宫格图片展示的具体代码,供大家参考,具体内容如下

属性


@property (strong,nonatomic)AVCaptureDevice * device;
@property (strong,nonatomic)AVCaptureDeviceInput * input;
@property (strong,nonatomic)AVCaptureMetadataOutput * output;
@property (strong,nonatomic)AVCaptureSession * session;
@property (strong,nonatomic)AVCaptureVideoPreviewLayer * layer; 
@property (nonatomic, strong)UIImageView *imageView;

二维码的生成


// 1.创建过滤器
  CIFilter *filter = [CIFilter filterWithName:@"CIQRCodeGenerator"];
 
  // 2.恢复默认
  [filter setDefaults];
 
  // 3.给过滤器添加数据(正则表达式/账号和密码)
  NSString *dataString = @"http://www.easck.com// 4.获取输出的二维码
  CIImage *outputImage = [filter outputImage];
 
  //因为生成的二维码模糊,所以通过createNonInterpolatedUIImageFormCIImage:outputImage来获得高清的二维码图片
 
  // 5.显示二维码
  self.imageView.image = [self createNonInterpolatedUIImageFormCIImage:outputImage withSize:200];

 * createNonInterpolatedUIImageFormCIImage:outputImage方法的实现


/**
 * 根据CIImage生成指定大小的UIImage
 *
 * @param image CIImage
 * @param size 图片宽度
 */
- (UIImage *)createNonInterpolatedUIImageFormCIImage:(CIImage *)image withSize:(CGFloat) size
{
  CGRect extent = CGRectIntegral(image.extent);
  CGFloat scale = MIN(size/CGRectGetWidth(extent), size/CGRectGetHeight(extent));
 
  // 1.创建bitmap;
  size_t width = CGRectGetWidth(extent) * scale;
  size_t height = CGRectGetHeight(extent) * scale;
  CGColorSpaceRef cs = CGColorSpaceCreateDeviceGray();
  CGContextRef bitmapRef = CGBitmapContextCreate(nil, width, height, 8, 0, cs, (CGBitmapInfo)kCGImageAlphaNone);
  CIContext *context = [CIContext contextWithOptions:nil];
  CGImageRef bitmapImage = [context createCGImage:image fromRect:extent];
  CGContextSetInterpolationQuality(bitmapRef, kCGInterpolationNone);
  CGContextScaleCTM(bitmapRef, scale, scale);
  CGContextDrawImage(bitmapRef, extent, bitmapImage);
 
  // 2.保存bitmap到图片
  CGImageRef scaledImage = CGBitmapContextCreateImage(bitmapRef);
  CGContextRelease(bitmapRef);
  CGImageRelease(bitmapImage);
  return [UIImage imageWithCGImage:scaledImage];
}

 二维码的扫描


// 1.创建捕捉会话
  AVCaptureSession *session = [[AVCaptureSession alloc] init];
  self.session = session;
 
  // 2.添加输入设备(数据从摄像头输入)
  AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
  AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:device error:nil];
  [session addInput:input];
 
  // 3.添加输出数据(示例对象-->类对象-->元类对象-->根元类对象)
  AVCaptureMetadataOutput *output = [[AVCaptureMetadataOutput alloc] init];
  [output setMetadataObjectsDelegate:self queue:dispatch_get_main_queue()];
  [session addOutput:output];
 
  // 3.1.设置输入元数据的类型(类型是二维码数据)
  [output setMetadataObjectTypes:@[AVMetadataObjectTypeQRCode]];
 
  // 4.添加扫描图层
  AVCaptureVideoPreviewLayer *layer = [AVCaptureVideoPreviewLayer layerWithSession:session];
  layer.frame = self.view.bounds;
  [self.view.layer addSublayer:layer];
  self.layer = layer;
 
  // 5.开始扫描
  [session startRunning];