Configuration and face recognition technology for iOS OPENCV

<span id="Label3"></p><p><p>As a very curious person, the face of the unknown world all want to Explore. So I did a personal face recognition demo. At present, the domestic about OPENCV technical articles are very few, are copying each other, the key is to copy a small part is not Complete. Time is long ago, and now some things do not. nothing, I am a real person, not much to say, directly on the Beginning. During the reference to the domestic many OPENCV articles, Code section Reference http://m.blog.csdn.net/blog/u013810454/27868973, you can VIEW. But he had a problem downloading the Project. I have this fusion of all the advantages, more comprehensive, from configuration to Use.</p></p><p><p>First let's configure OpenCV in the Xcode project.</p></p><p><p>1.OPENCV Download the framework under iOS and download the opencv2.framework First. Then drag directly into the previously created Project.</p></p><p><p><br></p></p><p><p>And then</p></p><p><p><br></p></p><p><p>And then</p></p><p><p><br></p></p><p><p>Now that the basic configuration is complete, it's time to show the real technology. Of course, don't forget to change. m to. mm in order to use C + +.</p></p><p><p></p></p><pre name="code" class="objc">#import "ViewController.h" #import <foundation/foundation.h>int currentvalue = 9; @interface viewcontroller () <uiimagepickercontrollerdelegate,uinavigationcontrollerdelegate>{//display Picture Uiimageview *_imageView; UIImage *image;} @end @implementation viewcontroller-(void) viewdidload {[super viewdidload]; Do any additional setup after loading the VIEW. [self createbutton]; Create a Uiimagepickercontroller object Uiimagepickercontroller *ctrl = [[uiimagepickercontroller alloc] init]; Set type Ctrl.sourcetype = uiimagepickercontrollersourcetypephotolibrary; Set Proxy ctrl.delegate = self; Show [self Presentviewcontroller:ctrl Animated:yes completion:nil]; Self.view.backgroundColor = [uicolor whitecolor]; Create a Uiimageview to display the selected picture _imageview = [[uiimageview alloc] initwithframe:cgrectmake (50, 100, 300, 400)]; [self.view addsubview:_imageview]; } #pragma mark-uiimagepickercontroller Agent-(void) imagepickercontroller: (uiimagEpickercontroller *) Picker didfinishpickingmediawithinfo: (nsdictionary *) info{//fetch to Selected picture image = Info[uiimagepickerc ontrolleroriginalimage]; Uiimageorientation imageorientation=image.imageorientation; If (imageorientation!=uiimageorientationup) {//the original picture can be displayed according to the angle of the camera, but UIImage cannot be judged, so the image obtained will turn left 90 degrees. The following is a partial uigraphicsbeginimagecontext (image.size) that adjusts the angle of the picture; [image drawinrect:cgrectmake (0, 0, image.size.width, image.size.height)]; Image = Uigraphicsgetimagefromcurrentimagecontext (); Uigraphicsendimagecontext (); Adjust picture angle finished}//processing picture _imageview.image = image; [picker Dismissviewcontrolleranimated:yes completion:nil]; }-(void) imagepickercontrollerdidcancel: (uiimagepickercontroller *) picker{[picker dismissviewcontrolleranimated: YES completion:nil];} Convert image to OpenCV image format-(iplimage *) createiplimagefromuiimage: (UIImage *) image {cgimageref Imageref = Image. cgimage; Cgcolorspaceref ColorSpace =Cgcolorspacecreatedevicergb (); Iplimage *iplimage = cvcreateimage (cvsize (image.size.width, image.size.height), ipl_depth_8u, 4); Cgcontextref contextref = cgbitmapcontextcreate (iplimage->imagedata, iplimage->width, iplimage->height, iplimage->depth, iplimage->widthstep, colorspace, kcgimagealphapremultipliedlast|kcgbitmapbyteorderdefault); Cgcontextdrawimage (contextref, cgrectmake (0, 0, image.size.width, image.size.height), imageref); Cgcontextrelease (contextref); Cgcolorspacerelease (colorspace); Iplimage *ret = cvcreateimage (cvgetsize (iplimage), ipl_depth_8u, 3); Cvcvtcolor (iplimage, ret, cv_rgba2bgr); Cvreleaseimage (&iplimage); Return ret;} -(void) opencvfacedetect {uiimage* img = [image copy]; If (img) {cvseterrmode (cv_errmodeparent); Iplimage *image = [self createiplimagefromuiimage:img]; Iplimage *grayimg = cvcreateimage (cvgetsize (image), ipl_depth_8u, 1); First to grayscale image Cvcvtcolor (image, grayimg, cv_bgr2gray); Reduce the input image by 4 times times to speed up the processing speed int scale = 4; Iplimage *small_image = cvcreateimage (cvsize (image->width/scale,image->height/scale), IPL_DEPTH_8U, 1); Cvresize (grayimg, small_image); Load classifier nsstring *path = [[nsbundle mainbundle] pathforresource:@ "haarcascade_frontalface_alt2" ofType:@ "xml"]; cvhaarclassifiercascade* cascade = (cvhaarclassifiercascade*) cvload ([path cstringusingencoding: nsasciistringencoding], null, null, null); cvmemstorage* storage = Cvcreatememstorage (0); Cvclearmemstorage (storage); Key section, using cvhaardetectobjects for detection, get a series of boxes cvseq* faces = cvhaardetectobjects (small_image, cascade, storage, 1.1, cur rentvalue, cv_haar_do_canny_pruning, cvsize (0,0), cvsize (0, 0)); NSLog (@ "faces:%d", faces->total); Create a canvas to mark a part of a human face Cgimageref Imageref = Img. cgimage; Cgcolorspaceref colorspace = Cgcolorspacecreatedevicergb (); Cgcontextref contextref = cgbitmapcontextcreate (NULL, img.size.width, img.size.height,8, img.size.width * 4,colorspace , kcgimagealphapremultipliedlast|kcgbitmapbyteorderdefault); Cgcontextdrawimage (contextref, cgrectmake (0, 0, img.size.width, img.size.height), imageref); Cgcontextsetlinewidth (contextref, 4); Cgcontextsetrgbstrokecolor (contextref, 1.0, 0.0, 0.0, 1); Mark the face for (int i = 0; i < faces->total; i++) {//Calc The rect of faces Cvrect Cvre CT = * (cvrect*) cvgetseqelem (faces, i); CGRect face_rect = cgcontextconvertrecttodevicespace (contextref, cgrectmake (cvrect.x*scale, cvrect.y*scale, cvrect.width*scale, cvrect.height*scale)); Cgcontextstrokerect (contextref, face_rect); } _imageview.image = [UIImage imaGewithcgimage:cgbitmapcontextcreateimage (contextref)]; }//detection is a bit time-consuming, open a new thread to handle It-(void) btn{[nsthread detachnewthreadselector: @selector (opencvfacedetect) totarget:self withob ject:nil];} -(void) Createbutton{UIButton *btn = [[UIButton alloc]init]; Btn.backgroundcolor = [uicolor redcolor]; Btn.frame = CGRectMake (0, 100, 30, 30); [BTN addtarget:self action: @selector (btn) forcontrolevents:uicontroleventtouchupinside]; [self.view addsubview:btn]; } @end</pre><br>ok, Now you can detect the face,<p><p></p></p><p><p><br></p></p><p><p>Isn't it magical, it's fun? Give it a try.</p></p> <p style="font-size:12px;"><p style="font-size:12px;">Copyright Notice: This article for Bo Master original article, without Bo Master permission not Reproduced.</p></p> <p><p>Configuration and face recognition technology for iOS OPENCV</p></p></span>