IOS生成二维码、扫二维码

有好多生成二维码以及扫二维码的第三方库，我这种方法是用系统自带的，他有个缺点就是生成的二维码太模糊，我这里进行了处理，遍历整个像素，对二维码进行颜色填充，使黑色加深

一、生成二维码

//1. 创建二维码滤镜
CIFilter *filer = [CIFilter filterWithName:@"CIQRCodeGenerator"];

//2.还原滤镜的初始设置
[filer setDefaults];

//3.将要隐藏在二维码中的字符串变成data
NSData *data = [@"123456" dataUsingEncoding:NSUTF8StringEncoding];

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

//5.生成二维码
CIImage *outputImage = [filer outputImage];
UIImage *image=[self createNonInterpolatedUIImageFormCIImage:outputImage withSize:250.0f];
//6.填充颜色后的二维码
codeImage =[self imageBlackToTransparent:image];

下面两个方法是处理二维码颜色的

#pragma mark - 二维码图片
//返回需要大小的UIImage
- (UIImage *)createNonInterpolatedUIImageFormCIImage:(CIImage *)image withSize:(CGFloat) size {
CGRect extent = CGRectIntegral(image.extent);
CGFloat scale = MIN(size/CGRectGetWidth(extent), size/CGRectGetHeight(extent));
// 创建bitmap
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);
return [UIImage imageWithCGImage:scaledImage];
}
void ProviderReleaseData (void *info, const void *data, size_t size){
free((void*)data);
}
//对二维码进行颜色填充
- (UIImage*)imageBlackToTransparent:(UIImage*)image{
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);
// 输出图片
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];
return resultUIImage;
}

运行效果：



中间的头像是叠在二维码上的，不会影响扫描结果，这里很简单就不共享代码了

二、扫二维码

导入

#import <AVFoundation/AVFoundation.h>

遵守协议

<AVCaptureMetadataOutputObjectsDelegate>

//
//  ScanQRCodeViewController.h
//  IM
//
//  Created by admin on 15/12/18.
//  Copyright © 2015年 ZBY. All rights reserved.
//

#import "BaseViewController.h"
#import <AVFoundation/AVFoundation.h>

@interface ScanQRCodeViewController : BaseViewController
<AVCaptureMetadataOutputObjectsDelegate>

@property (strong, nonatomic)  UIView *viewPreview;
@property (strong, nonatomic)  UILabel *lblStatus;
@property (strong, nonatomic)  UIButton *startBtn;

@property (strong, nonatomic) UIView *boxView;
@property (nonatomic) BOOL isReading;
@property (strong, nonatomic) CALayer *scanLayer;

-(BOOL)startReading;
-(void)stopReading;

//捕捉会话
@property (nonatomic, strong) AVCaptureSession *captureSession;
//展示layer
@property (nonatomic, strong) AVCaptureVideoPreviewLayer *videoPreviewLayer;

@end

//
//  ScanQRCodeViewController.m
//  IM
//
//  Created by admin on 15/12/18.
//  Copyright © 2015年 ZBY. All rights reserved.
//

#import "ScanQRCodeViewController.h"
#import "AddContactsViewController.h"

#define SCANVIEW_EdgeTop 50.0
#define SCANVIEW_EdgeLeft 50.0

#define TINTCOLOR_ALPHA 0.4  //浅色透明度
#define DARKCOLOR_ALPHA 1  //深色透明度
@interface ScanQRCodeViewController ()

@end

@implementation ScanQRCodeViewController

- (void)viewDidLoad {
[super viewDidLoad];

[self initBar:@"设置" titleName:@"扫描二维码"];

_viewPreview = [[UIView alloc]initWithFrame:CGRectMake(0, 64, WIDTH, HEIGHT-204)];
[self.view addSubview:_viewPreview];
_startBtn = [[UIButton alloc] initWithFrame:CGRectMake(0, HEIGHT-140, WIDTH, 40)];
[_startBtn setTitle:@"开始扫描" forState:UIControlStateNormal];
_startBtn.backgroundColor = MYCOLOR;
[_startBtn addTarget:self action:@selector(startStopReading:) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:_startBtn];
_lblStatus = [[UILabel alloc] initWithFrame:CGRectMake(10, HEIGHT-100, WIDTH-20, 100)];
//_lblStatus.backgroundColor = [UIColor whiteColor];
_lblStatus.numberOfLines = 0;
_lblStatus.textAlignment = NSTextAlignmentCenter;
_lblStatus.font = [UIFont systemFontOfSize:15];
[self.view addSubview:_lblStatus];

_captureSession = nil;
_isReading = NO;

[self startReading];
}

- (BOOL)startReading {
NSError *error;
//1.初始化捕捉设备（AVCaptureDevice），类型为AVMediaTypeVideo
AVCaptureDevice *captureDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
//2.用captureDevice创建输入流
AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:captureDevice error:&error];
if (!input) {
NSLog(@"%@", [error localizedDescription]);
return NO;
}
//3.创建媒体数据输出流
AVCaptureMetadataOutput *captureMetadataOutput = [[AVCaptureMetadataOutput alloc] init];
//4.实例化捕捉会话
_captureSession = [[AVCaptureSession alloc] init];
//4.1.将输入流添加到会话
[_captureSession addInput:input];
//4.2.将媒体输出流添加到会话中
[_captureSession addOutput:captureMetadataOutput];
//5.创建串行队列，并加媒体输出流添加到队列当中
dispatch_queue_t dispatchQueue;
dispatchQueue = dispatch_queue_create("myQueue", NULL);
//5.1.设置代理
[captureMetadataOutput setMetadataObjectsDelegate:self queue:dispatchQueue];
//5.2.设置输出媒体数据类型为QRCode
[captureMetadataOutput setMetadataObjectTypes:[NSArray arrayWithObject:AVMetadataObjectTypeQRCode]];
//6.实例化预览图层
_videoPreviewLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:_captureSession];
//7.设置预览图层填充方式
[_videoPreviewLayer setVideoGravity:AVLayerVideoGravityResizeAspectFill];
//8.设置图层的frame
[_videoPreviewLayer setFrame:_viewPreview.layer.bounds];
//9.将图层添加到预览view的图层上
[_viewPreview.layer addSublayer:_videoPreviewLayer];
//10.设置扫描范围
captureMetadataOutput.rectOfInterest = CGRectMake(0.2f, 0.2f, 0.8f, 0.8f);
//10.1.扫描框
_boxView = [[UIView alloc] initWithFrame:CGRectMake(40, (HEIGHT-204)/4, WIDTH-80, (HEIGHT-204)/2)];
_boxView.layer.borderColor = [UIColor greenColor].CGColor;
_boxView.layer.borderWidth = 1.0f;
[_viewPreview addSubview:_boxView];
//10.2.扫描线
_scanLayer = [[CALayer alloc] init];
_scanLayer.frame = CGRectMake(0, 0, _boxView.bounds.size.width, 1);
_scanLayer.backgroundColor = [UIColor brownColor].CGColor;
[_boxView.layer addSublayer:_scanLayer];
NSTimer *timer = [NSTimer scheduledTimerWithTimeInterval:0.2f target:self selector:@selector(moveScanLayer:) userInfo:nil repeats:YES];
[timer fire];

//10.开始扫描
[_captureSession startRunning];
return YES;
}

//实现AVCaptureMetadataOutputObjectsDelegate协议方法

#pragma mark - AVCaptureMetadataOutputObjectsDelegate
- (void)captureOutput:(AVCaptureOutput *)captureOutput didOutputMetadataObjects:(NSArray *)metadataObjects fromConnection:(AVCaptureConnection *)connection
{
//判断是否有数据
if (metadataObjects != nil && [metadataObjects count] > 0) {
AVMetadataMachineReadableCodeObject *metadataObj = [metadataObjects objectAtIndex:0];
//停止扫描
[self performSelectorOnMainThread:@selector(stopReading) withObject:nil waitUntilDone:NO];
NSLog(@"账号=%@",[metadataObj stringValue]);
//扫一扫加好友
//判断回传的数据类型
if ([[metadataObj type] isEqualToString:AVMetadataObjectTypeQRCode]) {
[_lblStatus performSelectorOnMainThread:@selector(setText:) withObject:@"正在添加好友" waitUntilDone:NO];
_isReading = NO;

//添加联系人
dispatch_async(dispatch_get_main_queue(), ^{
[self addContacts:[metadataObj stringValue]];

});

}

}
}
#pragma mark  添加联系人
-(void)addContacts:(NSString *)account{
AddContactsViewController *addController=[[AddContactsViewController alloc]init];
addController.userAccount=account;
addController.onControllerTitle=@"扫一扫";
[self.navigationController pushViewController:addController animated:YES];
}

- (void)moveScanLayer:(NSTimer *)timer
{
CGRect frame = _scanLayer.frame;
if (_boxView.frame.size.height < _scanLayer.frame.origin.y) {
frame.origin.y = 0;
_scanLayer.frame = frame;
}else{
frame.origin.y += 5;
[UIView animateWithDuration:0.1 animations:^{
_scanLayer.frame = frame;
}];
}
}

- (void)startStopReading:(id)sender {
if (!_isReading) {
if ([self startReading]) {
[_startBtn setTitle:@"停止扫描" forState:UIControlStateNormal];
[_lblStatus setText:@"正在扫描..."];
}
}
else{
[self stopReading];
[_startBtn setTitle:@"开始扫描" forState:UIControlStateNormal];
}
_isReading = !_isReading;
}

-(void)stopReading{
[_captureSession stopRunning];
_captureSession = nil;
[_scanLayer removeFromSuperlayer];
[_videoPreviewLayer removeFromSuperlayer];
}

-(void)viewWillAppear:(BOOL)animated{
[_startBtn setTitle:@"开始扫描" forState:UIControlStateNormal];
[_lblStatus performSelectorOnMainThread:@selector(setText:) withObject:@"" waitUntilDone:NO];
}

@end