QRCode&Barcode

CodeGenerator.h

#import <UIKit/UIKit.h>

@interface CodeGenerator : NSObject
+ (UIImage *)qrCodeForString:(NSString *)string;
+ (UIImage *)barCodeForString:(NSString *)string;
@end

CodeGenerator.m

#pragma mark - QRCode

+ (UIImage *)qrCodeForString:(NSString *)string {
    if (!string.length) return nil;

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

    NSData *data = [string dataUsingEncoding:NSUTF8StringEncoding];
    [filter setValue:data forKey:@"inputMessage"];

    CIImage *outputImage = [filter outputImage];

    CIContext *context = [CIContext contextWithOptions:nil];
    CGImageRef cgImage = [context createCGImage:outputImage
                                       fromRect:[outputImage extent]];

    UIImage *image = [UIImage imageWithCGImage:cgImage
                                         scale:1.
                                   orientation:UIImageOrientationUp];

    UIImage *resizedImage = [CodeGenerator resizeImage:image
                                                  rate:5.0];

    CGImageRelease(cgImage);

    return resizedImage;
}

#pragma mark - Barcode

+ (UIImage *)barCodeForString:(NSString *)string {
    if (!string.length) return nil;

    CIFilter *barCodeFilter = [CIFilter filterWithName:@"CICode128BarcodeGenerator"];
    [barCodeFilter setDefaults];

    NSData *barCodeData = [string dataUsingEncoding:NSASCIIStringEncoding];

    [barCodeFilter setValue:barCodeData forKey:@"inputMessage"];
    [barCodeFilter setValue:[NSNumber numberWithFloat:0] forKey:@"inputQuietSpace"];

    CIImage *outputImage = [barCodeFilter outputImage];
    CIContext *context = [CIContext contextWithOptions:nil];
    CGImageRef cgImage = [context createCGImage:outputImage
                                       fromRect:[outputImage extent]];

    UIImage *image = [UIImage imageWithCGImage:cgImage
                                         scale:1.
                                   orientation:UIImageOrientationUp];

    UIImage *resizedImage = [CodeGenerator resizeImage:image
                                                  rate:5.0];
    CGImageRelease(cgImage);

    return resizedImage;
}

#pragma mark - Util

+ (UIImage *)resizeImage:(UIImage *)image rate:(CGFloat)rate {
    UIImage *resized = nil;
    CGFloat width = image.size.width * rate;
    CGFloat height = image.size.height * rate;
    CGInterpolationQuality quality = kCGInterpolationNone;

    UIGraphicsBeginImageContext(CGSizeMake(width, height));
    CGContextRef context = UIGraphicsGetCurrentContext();
    CGContextSetInterpolationQuality(context, quality);
    [image drawInRect:CGRectMake(0, 0, width, height)];
    resized = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();

    return resized;
}