iOS taking photo programmatically

Question

I know this is possible, saw this in some apps (iGotYa is I believe the most famous). I know how to set up everything for taking photos, saving it and everything. But how ca

Answer 1

This is very simple, just use the AVFoundation reference guide:

https://developer.apple.com/library/ios/#documentation/AudioVideo/Conceptual/AVFoundationPG/Articles/04_MediaCapture.html

If you don't want the user to see the preview input you can just skip the set preview layer part of the code.

Edit: To be more detailed.

1)You set your capture configuration using the AVFoundation.

• Set the camera input to frontal, turn off flash etc etc.

2)You SKIP the part where the video preview layer is set.

3)You call the captureStillImageAsynchronouslyFromConnection:completionHandler: method whenever you want the picture to be taken.

Note: If you want the flash to not be heard and such then you might be violating the user rights in some countries (japan for example). One workaround I know of to do so is by capturing a frame of a video (does not trigger flash).

Answer 2

You can also do it without AVFoundation and it is in my opinion an easier way to implement it using only the UIImagePickerController. There are 3 conditions:

1. Obviously the device needs to have a camera
2. You must hide the camera controls
3. Then simply use the takePicture method from UIImagePickerController

Below is a simple example that you woul typically trigger after a button push

- (IBAction)takePhoto:(id)sender 
{
    UIImagePickerController *picker = [[UIImagePickerController alloc] init];
    picker.delegate = self;
    picker.sourceType = UIImagePickerControllerSourceTypeCamera;
    picker.cameraDevice = UIImagePickerControllerCameraDeviceFront;
    picker.showsCameraControls = NO;
    [self presentViewController:picker animated:YES
                     completion:^ {
                         [picker takePicture];
                     }];
}

Answer 3

Swift 5.2

For reference https://gist.github.com/hadanischal/33054429b18287c12ed4f4b8d45a1701

Info.plist

<key>NSCameraUsageDescription</key>
<string>Access camera</string>
<key>NSPhotoLibraryUsageDescription</key>
<string>Access PhotoLibrary</string>

AVFoundationHelper

import AVFoundation

enum CameraStatus {
    case notDetermined
    case restricted
    case denied
    case authorized
}

protocol AVFoundationHelperProtocol: AnyObject {
    // MARK: - Check and Respond to Camera Authorization Status

    var authorizationStatus: CameraStatus { get }

    // MARK: - Request Camera Permission

    func requestAccess(completionHandler handler: @escaping (Bool) -> Void)
}

final class AVFoundationHelper: AVFoundationHelperProtocol {
    // MARK: - Check and Respond to Camera Authorization Status

    var authorizationStatus: CameraStatus {
        let cameraAuthorizationStatus = AVCaptureDevice.authorizationStatus(for: .video)
        switch cameraAuthorizationStatus {
        case .notDetermined:
            return CameraStatus.notDetermined
        case .authorized:
            return CameraStatus.authorized
        case .restricted:
            return CameraStatus.restricted
        case .denied:
            return CameraStatus.denied
        @unknown default:
            return CameraStatus.notDetermined
        }
    }

    // MARK: - Request Camera Permission

    func requestAccess(completionHandler handler: @escaping (Bool) -> Void) {
        AVCaptureDevice.requestAccess(for: .video, completionHandler: { accessGranted in
            handler(accessGranted)
        })
    }
}

ViewController

import UIKit

final class ViewController: UIViewController {
    @IBOutlet var cameraAccessButton: UIButton!
    @IBOutlet var photoImageView: UIImageView!

    private var model: AVFoundationHelperProtocol = AVFoundationHelper()

    override func viewDidLoad() {
        super.viewDidLoad()
    }

    @IBAction func cameraButtonPressed(_: Any) {
        let status = model.authorizationStatus
        switch status {
        case .notDetermined:
            model.requestAccess { hasAccess in
                if hasAccess {
                    DispatchQueue.main.async {
                        self.showCameraReader()
                    }
                } else {
                    self.alertCameraAccessNeeded()
                }
            }
        case .restricted, .denied:
            alertCameraAccessNeeded()

        case .authorized:
            showCameraReader()
        }
    }

    private func alertCameraAccessNeeded() {
        let appName = "This app Name"

        let alert = UIAlertController(title: "This feature requires Camera Access",
                                      message: "In iPhone settings, tap \(appName) and turn on Camera access",
                                      preferredStyle: UIAlertController.Style.alert)

        let actionSettings = UIAlertAction(title: "Settings", style: .default, handler: { _ -> Void in
            guard let settingsAppURL = URL(string: UIApplication.openSettingsURLString) else { return }
            UIApplication.shared.open(settingsAppURL)
        })

        let actionCancel = UIAlertAction(title: "Cancel", style: .destructive, handler: { _ -> Void in
        })

        alert.addAction(actionSettings)
        alert.addAction(actionCancel)

        present(alert, animated: true, completion: nil)
    }
}

extension ViewController: UIImagePickerControllerDelegate, UINavigationControllerDelegate {
    private func showCameraReader() {
        if UIImagePickerController.isSourceTypeAvailable(.camera) {
            let imagePicker = UIImagePickerController()
            imagePicker.sourceType = .camera
            imagePicker.allowsEditing = true
            imagePicker.delegate = self
            present(imagePicker, animated: true)

        } else if UIImagePickerController.isSourceTypeAvailable(.photoLibrary) {
            let imagePicker = UIImagePickerController()
            imagePicker.sourceType = .photoLibrary
            imagePicker.allowsEditing = true
            imagePicker.delegate = self
            present(imagePicker, animated: true)

        } else {
            // TODO: Implement proper alert
            alertCameraAccessNeeded()
        }
    }

    func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey: Any]) {
        picker.dismiss(animated: true)

        guard let image = info[.editedImage] as? UIImage else {
            print("No image found")
            return
        }
        photoImageView.image = image
        // print out the image size as a test
        print(image.size)
    }
}

Objective C

In .h file

@interface ABCViewController : UIViewController

@property (strong, nonatomic) IBOutlet UIImageView *imageView;

- (IBAction)takePhoto:  (UIButton *)sender;
- (IBAction)selectPhoto:(UIButton *)sender;

@end

In .m file

@interface ABCViewController : UIViewController <UIImagePickerControllerDelegate, UINavigationControllerDelegate>

- (IBAction)takePhoto:(UIButton *)sender {


if (![UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]) {
    
        UIAlertView *myAlertView = [[UIAlertView alloc] initWithTitle:@"Error"
                                                        message:@"Device has no camera"
                                                        delegate:nil
                                                        cancelButtonTitle:@"OK"
                                                        otherButtonTitles: nil];
        
        [myAlertView show];
        
    } else {
    
    UIImagePickerController *picker = [[UIImagePickerController alloc] init];
    picker.delegate = self;
    picker.allowsEditing = YES;
    picker.sourceType = UIImagePickerControllerSourceTypeCamera;
    
    [self presentViewController:picker animated:YES completion:NULL];

}
    
}

- (IBAction)selectPhoto:(UIButton *)sender {
    
    UIImagePickerController *picker = [[UIImagePickerController alloc] init];
    picker.delegate = self;
    picker.allowsEditing = YES;
    picker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
    
    [self presentViewController:picker animated:YES completion:NULL];

    
}

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {
    
    UIImage *chosenImage = info[UIImagePickerControllerEditedImage];
    self.imageView.image = chosenImage;
    
    [picker dismissViewControllerAnimated:YES completion:NULL];
    
}


- (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker {

    [picker dismissViewControllerAnimated:YES completion:NULL];
    
}

Answer 4

VLBCameraView is a library that uses AVFoundation to take photo.

A preview is shown in the view, which you can then call the method VLBCameraView#takePicture programmatically to take a photo.

Comes with CocoaPods.

Answer 5

Here is the code for Objective -C Custom Camera. You can add features, buttons according to your wish.

#import "CustomCameraVC.h"

@interface CustomCameraVC ()  {
    BOOL frontCamera;
}
@property (strong,nonatomic) AVCaptureSession *captureSession;
@property (strong,nonatomic) AVCaptureStillImageOutput *stillImageOutput;
@property (strong,nonatomic) AVCaptureVideoPreviewLayer *videoPreviewLayer;
@property (weak, nonatomic) IBOutlet UIView *viewCamera;


@end

@implementation CustomCameraVC

- (void)viewDidLoad {
    [super viewDidLoad];        
}

-(void)viewWillAppear:(BOOL)animated  {
    [super viewWillAppear:YES];
    frontCamera = NO;
    [self showCameraWithFrontCamera:frontCamera];

}

-(void)showCameraWithFrontCamera:(BOOL)flag {
    self.captureSession = [[AVCaptureSession alloc]init];
    self.captureSession.sessionPreset = AVCaptureSessionPresetPhoto;
    AVCaptureDevice *captureDevice;
    if(flag)  {
      captureDevice= [self frontCamera];
    }
    else {
      captureDevice= [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
    }
    NSError *error = nil;
    AVCaptureDeviceInput *input =   [AVCaptureDeviceInput deviceInputWithDevice:captureDevice error:&error];

    [self.captureSession addInput:input];
    self.stillImageOutput = [AVCaptureStillImageOutput new];
    self.stillImageOutput.outputSettings = @{AVVideoCodecKey:AVVideoCodecJPEG};
    [self.captureSession addOutput:_stillImageOutput];
    self.videoPreviewLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:self.captureSession];

    self.videoPreviewLayer.videoGravity = AVLayerVideoGravityResizeAspectFill;
    self.videoPreviewLayer.connection.videoOrientation = AVCaptureVideoOrientationPortrait;
    [self.viewCamera.layer addSublayer:self.videoPreviewLayer];
    [self.captureSession startRunning];
    self.videoPreviewLayer.frame = self.viewCamera.bounds;
}


- (AVCaptureDevice *)frontCamera {
    NSArray *devices = [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo];
    for (AVCaptureDevice *device in devices) {
        if ([device position] == AVCaptureDevicePositionFront) {
            return device;
        }
    }
    return nil;
}


- (IBAction)btnCaptureImagePressed:(id)sender {

     AVCaptureConnection * videoConnection =  [_stillImageOutput connectionWithMediaType:AVMediaTypeVideo];

    [_stillImageOutput captureStillImageAsynchronouslyFromConnection:videoConnection completionHandler:^(CMSampleBufferRef  _Nullable sampleBuffer, NSError * _Nullable error) {
       NSData *imageData =  [AVCaptureStillImageOutput jpegStillImageNSDataRepresentation:sampleBuffer];
        UIImage *image = [[UIImage alloc]initWithData: imageData];
        UIImageWriteToSavedPhotosAlbum(image, nil, nil, nil);
    }];

}

@end