#pragma mark - 生成二维码图片
+ (UIImage *)qrImageForString:(NSString *)string imageSize:(CGFloat)Imagesize logoImageSize:(CGFloat)waterImagesize{
CIFilter *filter = [CIFilter filterWithName:@"CIQRCodeGenerator"];
[filter setDefaults];
NSData *data = [string dataUsingEncoding:NSUTF8StringEncoding];
[filter setValue:data forKey:@"inputMessage"];//通过kvo方式给一个字符串,生成二维码
[filter setValue:@"H" forKey:@"inputCorrectionLevel"];//设置二维码的纠错水平,越高纠错水平越高,可以污损的范围越大
CIImage *outPutImage = [filter outputImage];//拿到二维码图片
return [[self alloc] createNonInterpolatedUIImageFormCIImage:outPutImage withSize:Imagesize waterImageSize:waterImagesize];
}
- (UIImage *)createNonInterpolatedUIImageFormCIImage:(CIImage *)image withSize:(CGFloat) size waterImageSize:(CGFloat)waterImagesize{
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;
//创建一个DeviceGray颜色空间
CGColorSpaceRef cs = CGColorSpaceCreateDeviceGray();
//CGBitmapContextCreate(void * _Nullable data, size_t width, size_t height, size_t bitsPerComponent, size_t bytesPerRow, CGColorSpaceRef _Nullable space, uint32_t bitmapInfo)
//width:图片宽度像素
//height:图片高度像素
//bitsPerComponent:每个颜色的比特值,例如在rgba-32模式下为8
//bitmapInfo:指定的位图应该包含一个alpha通道。
CGContextRef bitmapRef = CGBitmapContextCreate(nil, width, height, 8, 0, cs, (CGBitmapInfo)kCGImageAlphaNone);
CIContext *context = [CIContext contextWithOptions:nil];
//创建CoreGraphics image
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);
//原图
UIImage *outputImage = [UIImage imageWithCGImage:scaledImage];
outputImage = [UIImage specialColorImage:outputImage withRed:102 green:102 blue:102];
//给二维码加 logo 图
UIGraphicsBeginImageContextWithOptions(outputImage.size, NO, [[UIScreen mainScreen] scale]);
[outputImage drawInRect:CGRectMake(0,0 , size, size)];
//logo图
UIImage *waterimage = [UIImage imageNamed:@"applogo"];
//把logo图画到生成的二维码图片上,注意尺寸不要太大(最大不超过二维码图片的%30),太大会造成扫不出来
[waterimage drawInRect:CGRectMake((size-waterImagesize)/2.0, (size-waterImagesize)/2.0, waterImagesize, waterImagesize)];
UIImage *newPic = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return newPic;
}
void ProviderReleaseData (void *info, const void *data, size_t size){
free((void*)data);
}
//改变二维码颜色
+ (UIImage *)specialColorImage:(UIImage *)image withRed:(CGFloat)red green:(CGFloat)green blue:(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 colorSpaceRef = CGColorSpaceCreateDeviceRGB();
CGContextRef contextRef = CGBitmapContextCreate(rgbImageBuf, imageWidth, imageHeight, 8, bytesPerRow, colorSpaceRef, kCGBitmapByteOrder32Little | kCGImageAlphaNoneSkipLast);
CGContextDrawImage(contextRef, 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;
}
}
CGDataProviderRef dataProviderRef = CGDataProviderCreateWithData(NULL, rgbImageBuf, bytesPerRow * imageHeight,ProviderReleaseData);
CGImageRef imageRef = CGImageCreate(imageWidth, imageHeight, 8, 32, bytesPerRow, colorSpaceRef,
kCGImageAlphaLast | kCGBitmapByteOrder32Little, dataProviderRef,
NULL, true, kCGRenderingIntentDefault);
CGDataProviderRelease(dataProviderRef);
UIImage* img = [UIImage imageWithCGImage:imageRef];
//Release
CGImageRelease(imageRef);
CGContextRelease(contextRef);
CGColorSpaceRelease(colorSpaceRef);
return img;
}