IOS创建二维码

  

   

    

     

    
    

     

      //调用
     
    
   

    

     

    
    

     
    UIImage *qrcode = [self createNonInterpolatedUIImageFormCIImage:[self createQRForString:@"http://www.baidu.com"] withSize:190.0f];
     
    
   

    

     

    
    

     
    UIImage *customQrcode = [self imageBlackToTransparent:qrcode withRed:0.0f andGreen:0.0f andBlue:0.0f];
     
    
   

    

     

    
    

     
    self.erweimaImg.image = customQrcode;
     
    
  
 

  

   

    

     

    
    

     

      #pragma mark - InterpolatedUIImage
     
    
   

    

     

    
    

     

      - (UIImage *)createNonInterpolatedUIImageFormCIImage:(CIImage *)image withSize:(CGFloat) size {
     
    
   

    

     

    
    

     
    CGRect extent = CGRectIntegral(image.extent);
     
    
   

    

     

    
    

     
    CGFloat scale = MIN(size/CGRectGetWidth(extent), size/CGRectGetHeight(extent));
     
    
   

    

     

    
    

     
    // create a bitmap image that we'll draw into a bitmap context at the desired size;
     
    
   

    

     

    
    

     

          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);
     
    
   

    

     

    
    

     
    // Create an image with the contents of our bitmap
     
    
   

    

     

    
    

     
    CGImageRef scaledImage = CGBitmapContextCreateImage(bitmapRef);
     
    
   

    

     

    
    

     
    // Cleanup
     
    
   

    

     

    
    

     
    CGContextRelease(bitmapRef);
     
    
   

    

     

    
    

     
    CGImageRelease(bitmapImage);
     
    
   

    

     

    
    

     
    return [UIImage imageWithCGImage:scaledImage];
     
    
   

    

     

    
    

     

      }
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      #pragma mark - QRCodeGenerator
     
    
   

    

     

    
    

     

      - (CIImage *)createQRForString:(NSString *)qrString {
     
    
   

    

     

    
    

     
    // Need to convert the string to a UTF-8 encoded NSData object
     
    
   

    

     

    
    

     
    NSData *stringData = [qrString dataUsingEncoding:NSUTF8StringEncoding];
     
    
   

    

     

    
    

     
    // Create the filter
     
    
   

    

     

    
    

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

    

     

    
    

     
    // Set the message content and error-correction level
     
    
   

    

     

    
    

     

          [qrFilter setValue:stringData forKey:@"inputMessage"];
     
    
   

    

     

    
    

     

          [qrFilter setValue:@"M" forKey:@"inputCorrectionLevel"];
     
    
   

    

     

    
    

     
    // Send the image back
     
    
   

    

     

    
    

     
    return qrFilter.outputImage;
     
    
   

    

     

    
    

     

      }
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      #pragma mark - imageToTransparent
     
    
   

    

     

    
    

     

      void ProviderReleaseData (void *info, const void *data, size_t size){
     
    
   

    

     

    
    

     

          free((void*)data);
     
    
   

    

     

    
    

     

      }
     
    
   

    

     

    
    

     

      - (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);
     
    
   

    

     

    
    

     
    // create context
     
    
   

    

     

    
    

     
    CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
     
    
   

    

     

    
    

     
    CGContextRef context = CGBitmapContextCreate(rgbImageBuf, imageWidth, imageHeight, 8, bytesPerRow, colorSpace,
     
    
   

    

     

    
    

     

                                                       kCGBitmapByteOrder32Little | kCGImageAlphaNoneSkipLast);
     
    
   

    

     

    
    

     
    CGContextDrawImage(context, CGRectMake(0, 0, imageWidth, imageHeight), image.CGImage);
     
    
   

    

     

    
    

     
    // traverse pixe
     
    
   

    

     

    
    

     
    int pixelNum = imageWidth * imageHeight;
     
    
   

    

     

    
    

     

          uint32_t* pCurPtr = rgbImageBuf;
     
    
   

    

     

    
    

     
    for (int i = 0; i < pixelNum; i++, pCurPtr++){
     
    
   

    

     

    
    

     
        if ((*pCurPtr & 0xFFFFFF00) < 0x99999900){
     
    
   

    

     

    
    

     
            // change color
     
    
   

    

     

    
    

     

                  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;
     
    
   

    

     

    
    

     

              }
     
    
   

    

     

    
    

     

          }
     
    
   

    

     

    
    

     
    // context to image
     
    
   

    

     

    
    

     
    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];
     
    
   

    

     

    
    

     
    // release
     
    
   

    

     

    
    

     
    CGImageRelease(imageRef);
     
    
   

    

     

    
    

     
    CGContextRelease(context);
     
    
   

    

     

    
    

     
    CGColorSpaceRelease(colorSpace);
     
    
   

    

     

    
    

     
    return resultUIImage;
     
    
   

    

     

    
    

     

      }
     
    
  
 

  
 
 

文章来源: zzzili.blog.csdn.net，作者：清雨小竹，版权归原作者所有，如需转载，请联系作者。

原文链接：zzzili.blog.csdn.net/article/details/49759121