iOS7后 苹果 二维码生成与扫描
本文是查阅网上资料和demo后整理出来的, 为了日后查阅以及其他人需要只用
之前使用的是第三方库, 最近听说iOS7后, 苹果原生的二维码扫描功能效率更高, 于是学习了一下, 顺便也把生成加上.
/**
* 打开二维码 扫描
*/
-(void)openCaptureMetada{
// Do any additional setup after loading the view, typically from a nib.
//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];
if(!device)
{
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"提示" message:@"获取设备失败" delegate:nil cancelButtonTitle:@"确定" otherButtonTitles:nil, nil];
[alert show];
return;
}
//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];
// 扫描区域为屏幕坐标的(50,100,200,200)
output.rectOfInterest = CGRectMake(100.f/screenHeight, 50.f/screenWidth, 200.f/screenHeight, 200.f/screenWidth);
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];
}
//// 是否有相机及后置镜头
//- (BOOL)validateCamera {
// return [UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera] &&
// [UIImagePickerController isCameraDeviceAvailable:UIImagePickerControllerCameraDeviceRear];
//}
-(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);
[session stopRunning];
}
}
#pragma mark---- 生成二维码
/**
* 转换 CIImage
*
* @param string 生成二维码的内容
*
* @return CIImage
*/
- (CIImage *)createTWMForString:(NSString *)string {
CIFilter *ewmFilter = [CIFilter filterWithName:@"CIQRCodeGenerator"];
// 内容
[ewmFilter setValue:[string dataUsingEncoding:NSUTF8StringEncoding] forKey:@"inputMessage"];
// 纠错级别
[ewmFilter setValue:@"M" forKey:@"inputCorrectionLevel"];
return ewmFilter.outputImage;
}
/**
* CIImage 转换 UIImageView
*
* @param image CIImage
* @param size 决定了图片的大小
*
* @return UIImageView.frame相同, size越大, 二维码图片越清晰
*/
- (UIImage *)createNonInterpolatedUIImageFormCIImage:(CIImage *)image withSize:(CGFloat) size {
// 位图
CGRect extent = CGRectIntegral(image.extent);
CGFloat scale = MIN(size/CGRectGetWidth(extent), size/CGRectGetHeight(extent));
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);
// 保存bitmap到图片
CGImageRef scaledImage = CGBitmapContextCreateImage(bitmapRef);
CGContextRelease(bitmapRef);
CGImageRelease(bitmapImage);
return [UIImage imageWithCGImage:scaledImage];
}
void ProviderReleaseData (void *info, const void *data, size_t size) {
free((void*)data);
}
/**
* // 1.更改二维码颜色
*
* @param image
* UIImage及颜色传入这个方法, 用新生成的UIImage赋给ImageView.image.
* 注意 ：imageView.contentMode = UIViewContentModeScaleAspectFit
*
*/
- (UIImage*)imageBlackToTransparent:(UIImage*)image withRed:(CGFloat)red andGreen:(CGFloat)green andBlue:(CGFloat)blue {
const int imageWidth = image.size.width;
const int imageHeight = image.size.height;
size_t bytesPerRow = imageWidth * 4;
uint32_t *rgbImageBuf = (uint32_t *)malloc(bytesPerRow * imageHeight);
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
CGContextRef context = CGBitmapContextCreate(rgbImageBuf, imageWidth, imageHeight, 8, bytesPerRow, colorSpace, kCGBitmapByteOrder32Little | kCGImageAlphaNoneSkipLast);
CGContextDrawImage(context, CGRectMake(0, 0, imageWidth, imageHeight), image.CGImage);
int pixelNum = imageWidth * imageHeight;
uint32_t *pCurPtr = rgbImageBuf;
for (int i = 0; i < pixelNum; i++, pCurPtr++) {
if ((*pCurPtr & 0xFFFFFF00) < 0x99999900) {
// 改成下面的代码，会将图片转成想要的颜色
uint8_t *ptr = (uint8_t *)pCurPtr;
ptr[3] = red; //0~255
ptr[2] = green;
ptr[1] = blue;
}
else {
uint8_t *ptr = (uint8_t *)pCurPtr;
ptr[0] = 0;
}
}
CGDataProviderRef dataProvider = CGDataProviderCreateWithData(NULL, rgbImageBuf, bytesPerRow * imageHeight, ProviderReleaseData);
CGImageRef imageRef = CGImageCreate(imageWidth, imageHeight, 8, 32, bytesPerRow, colorSpace, kCGImageAlphaLast | kCGBitmapByteOrder32Little, dataProvider, NULL, true, kCGRenderingIntentDefault);
CGDataProviderRelease(dataProvider);
UIImage *resultUIImage = [UIImage imageWithCGImage:imageRef];
CGImageRelease(imageRef);
CGContextRelease(context);
CGColorSpaceRelease(colorSpace);
return resultUIImage;
}
