Face Detection Example in iOS

Here in this Example i will show how to detect face on image.

Here we need two framework CoreImage & QuartzCore.
Let Start.
.h

#import <UIKit/UIKit.h>

@interface ViewController : UIViewController

@property (retain, nonatomic) IBOutlet UIButton *btnScanFace;

- (IBAction)btnScanFace:(id)sender;

@property (retain, nonatomic) IBOutlet UIImageView *imgView;

@end

.m

#import "ViewController.h"

#import <CoreImage/CoreImage.h>

#import <QuartzCore/QuartzCore.h>

- (void)viewDidLoad

{

    [super viewDidLoad];

    self.imgView.image=[UIImage imageNamed:@"family.png"];

}

- (IBAction)btnScanFace:(id)sender {

 // draw a CI image with the previously loaded picture

    CIImage* image1=[CIImage imageWithCGImage:self.imgView.image.CGImage];

 // create a face detector - since speed is not an issue we'll use a high accuracy

    // detector

    CIDetector* detector1=[CIDetector detectorOfType:CIDetectorTypeFace context:nil options:[NSDictionary dictionaryWithObject:CIDetectorAccuracyHigh forKey:CIDetectorAccuracy]];

// create an array containing all the detected faces from the detector  

    NSArray *feature1=[detector1 featuresInImage:image1];

    NSLog(@"%d",[feature1 count]);

// Here i use frameview because ciimage and uiimage are inversely if we leave as it is than detection will occur but show in different direction. 

    UIView *frameview=[[UIView alloc] initWithFrame:CGRectMake(self.imgView.bounds.origin.x, self.imgView.bounds.origin.y, self.imgView.image.size.width, self.imgView.image.size.height)];

 // we'll iterate through every detected face.  CIFaceFeature provides us

    // with the width for the entire face, and the coordinates of each eye

    // and the mouth if detected.  Also provided are BOOL's for the eye's and

    // mouth so we can check if they already exist.

    for (CIFaceFeature * faceFeature1 in feature1) {

// create a UIView using the bounds of the face

        //UIView* faceView1 = [[UIView alloc] initWithFrame:faceFeature.bounds];

UIView *faceView1=[[UIView alloc]initWithFrame:CGRectMake(faceFeature1.bounds.origin.x, faceFeature1.bounds.origin.y-15, faceFeature1.bounds.size.width, faceFeature1.bounds.size.height + 40)];

// Border is set

faceView1.layer.borderWidth=1;

faceView1.layer.borderColor=[[UIColor blackColor] CGColor];

[frameview addSubview:faceView1];

}

    [frameview setTransform:CGAffineTransformMakeScale(1, -1)];

    [self.view addSubview:frameview];

}