iOS comes with scan and generate QR code

1. Two-dimensional code generation

Libqrencode Introduction: is a C language to parse the two-dimensional barcode (QRCode) library, Libqrencode through the mobile phone's CCD camera to scan the two-dimensional barcode.

To import the Libqrencode library, the following direct code:

#import <Foundation/Foundation.h> @interface qrcodegenerator:nsobject+ (UIImage *) qrimageforstring: (NSString * ) string imageSize: (cgfloat) size;+ (UIImage *) Twodimensioncodeimage: (UIImage *) Twodimensioncode withavatarimage: ( UIImage *) Avatarimage; @end

#import "QRCodeGenerator.h" #import "Qrencode.h" enum {qr_margin = 3}; @implementation qrcodegenerator+ (void) Drawqrcode :(QRCode *) Code context: (CGCONTEXTREF) CTX Size: (cgfloat) Size {unsigned char *data = 0;int Width;data = Code->data;widt H = code->width;float Zoom = (double) size/(code->width + 2.0 * qr_margin); CGRect Rectdraw = CGRectMake (0, 0, zoom, zoom);//Drawcgcontextsetfillcolor (CTX, cgcolorgetcomponents ([Uicolor Blackcolor]. Cgcolor)) (int i = 0; i < width; ++i) {for (int j = 0; J < width; ++j) {if (*data & 1) {Rectdraw.origin = Cgpoi Ntmake ((j + qr_margin) * Zoom, (i + qr_margin) * zoom); Cgcontextaddrect (CTX, Rectdraw);} ++data;}} Cgcontextfillpath (CTX);} + (UIImage *) qrimageforstring: (NSString *) string imageSize: (cgfloat) Size {if (![ String length]) {return nil;} QRCode *code = qrcode_encodestring ([string utf8string], 0, qr_eclevel_l, qr_mode_8, 1); if (!code) {return nil;} Create Contextcgcolorspaceref colorspace = Cgcolorspacecreatedevicergb (); Cgcontextref CTX =Cgbitmapcontextcreate (0, size, size, 8, size * 4, colorspace, kcgimagealphapremultipliedlast); Cgaffinetransform TranslateTransform = cgaffinetransformmaketranslation (0,-size); Cgaffinetransform ScaleTransform = Cgaffinetransformmakescale (1,-1); CGCONTEXTCONCATCTM (CTX, Cgaffinetransformconcat (TranslateTransform, ScaleTransform));//Draw QR on this context[ Qrcodegenerator drawqrcode:code context:ctx size:size];//get imagecgimageref qrcgimage = CGBitmapContextCreateImage ( CTX); UIImage * Qrimage = [UIImage imagewithcgimage:qrcgimage];//some releasescgcontextrelease (CTX); Cgimagerelease (Qrcgimage); Cgcolorspacerelease (ColorSpace); Qrcode_free (code); return qrimage;} + (UIImage *) Twodimensioncodeimage: (UIImage *) Twodimensioncode withavatarimage: (UIImage *) avatarimage{//Two-dime        Nsion code QR code cgsize size = twodimensioncode.size;                Cgsize size2 =cgsizemake (1.0/5.5 * size.width, 1.0/5.5 * size.height);                Uigraphicsbeginimagecontext (size); [TwodiMensioncode drawinrect:cgrectmake (0, 0, Size.width, size.height)]; [Self avatarimage:avatarimage] Drawinrect:cgrectmake ((size.width-size2.width)/2.0, (Size.height-size2.height)/2.                0, Size2.width, size2.height)];        UIImage *resultingimage =uigraphicsgetimagefromcurrentimagecontext ();        Uigraphicsendimagecontext ();    return resultingimage; }+ (UIImage *) Avatarimage: (UIImage *) avatarimage{UIImage * avatarbackgroudimage = [UIImage imagenamed:@ "Icon.png"        ];        Cgsize size = avatarbackgroudimage.size;                Uigraphicsbeginimagecontext (size);        [Avatarbackgroudimage drawinrect:cgrectmake (0, 0, Size.width, size.height)];                [Avatarimage Drawinrect:cgrectmake (Ten, size.width-20, size.height-20)];        UIImage *resultingimage =uigraphicsgetimagefromcurrentimagecontext ();        Uigraphicsendimagecontext ();    return resultingimage; } @end

2. Scanning

IOS7 Apple introduced its own scanning function, the following direct code:

-(void) Viewwillappear: (BOOL) animated{[self setupcamera];}        -(void) setupcamera{//Device _device = [Avcapturedevice defaultdevicewithmediatype:avmediatypevideo];        Input _input = [Avcapturedeviceinput deviceInputWithDevice:self.device error:nil];    Output _output = [[Avcapturemetadataoutput alloc]init];        [_output setmetadataobjectsdelegate:self Queue:dispatch_get_main_queue ()];    Session _session = [[Avcapturesession alloc]init];    [_session Setsessionpreset:avcapturesessionpresethigh];    if ([_session canAddInput:self.input]) {[_session addInput:self.input];    } if ([_session canAddOutput:self.output]) {[_session addOutput:self.output]; }//barcode type Avmetadataobjecttypeqrcode _output.metadataobjecttypes [Email protected][avmetadataobjecttypecode 128code,avmetadataobjecttypeupcecode,avmetadataobjecttypecode39code,avmetadataobjecttypecode39mod43code, Avmetadataobjecttypeean13code,avmetadataobjecttypEean8code,avmetadataobjecttypecode93code,avmetadataobjecttypepdf417code,avmetadataobjecttypeqrcode, Avmetadataobjecttypeazteccode,avmetadataobjecttypeinterleaved2of5code,avmetadataobjecttypeitf14code,        Avmetadataobjecttypedatamatrixcode];    Preview _preview =[avcapturevideopreviewlayer layerWithSession:self.session];    _preview.videogravity = Avlayervideogravityresizeaspectfill;    _preview.frame =cgrectmake (20,110,280,280);            [Self.view.layer InsertSublayer:self.preview atindex:0]; Start [_session startrunning];} #pragma mark avcapturemetadataoutputobjectsdelegate-(void) Captureoutput: (Avcaptureoutput *) captureoutput Didoutputmetadataobjects: (Nsarray *) metadataobjects fromconnection: (avcaptureconnection *) connection{NSString *str        Ingvalue; if ([metadataobjects count] >0) {avmetadatamachinereadablecodeobject * metadataobject = [Metadataobjects obj        ECTATINDEX:0];    StringValue = Metadataobject.stringvalue; } [_session SToprunning]; Uialertview * alert = [[Uialertview alloc]initwithtitle:@ "Prompt" message:[nsstring stringwithformat:@ "Result:%@", StringValue    ] delegate:self cancelbuttontitle:nil otherbuttontitles:@ "Know", @ "rescan", nil]; [Alert show];}        -(void) Alertview: (Uialertview *) Alertview Clickedbuttonatindex: (Nsinteger) buttonindex{if (Buttonindex = = 0) {         [Self dismissviewcontrolleranimated:yes completion:^ {[timer invalidate];    }];    } else {[_session startrunning]; }}

iOS comes with scan and generate QR code