屏幕截圖，二維碼生成

UIGraphicsBeginImageContextWithOptions(CGSizeMake(tamplateView.frame.size.width, 548*scaleRation),NO, 0.0);     //設置截屏大小

    [[tamplateView layer] renderInContext:UIGraphicsGetCurrentContext()];

    UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();

    UIGraphicsEndImageContext();

- (UIImage *)generateQRCode:(NSString *)code width:(CGFloat)width height:(CGFloat)height {

    

  

  // 生成二維碼圖片

    CIImage *qrcodeImage;

    NSData *data = [code dataUsingEncoding:NSISOLatin1StringEncoding allowLossyConversion:false];

    CIFilter *filter = [CIFilter filterWithName:@"CIQRCodeGenerator"];

    

    [filter setValue:data forKey:@"inputMessage"];

    [filter setValue:@"H" forKey:@"inputCorrectionLevel"];

    qrcodeImage = [filter outputImage];

    

    // 消除模糊

//    CGFloat scaleX = width / qrcodeImage.extent.size.width; // extent 返回圖片的frame

//    CGFloat scaleY = height / qrcodeImage.extent.size.height;

//    CIImage *transformedImage = [qrcodeImage imageByApplyingTransform:CGAffineTransformScale(CGAffineTransformIdentity, scaleX, scaleY)];

    return [UIImage imageWithCIImage:qrcodeImage];

}