相机视图作为iOS中的子视图

Question

I'll start with saying that I am new to objective-c and iOS-programming.

What I want to do is to display camera as a part of a view, like a rectangle in the upper part of a screen, where should I start?

(What GUI-component for the "camera view"? AVCamCaptureManager or UIImagePickerController ?)

Answer 1

You can use the AVFoundation to do that. A good starting point is to see the WWDC videos (since 2011) related with AVFoundation and Camera.

The Apple's example code for AVCam project is a very good starting point.

Here's an example of what you can do.

First you need to instantiate a capture session:

AVCaptureSession *session = [[AVCaptureSession alloc] init];
session.sessionPreset = AVCaptureSessionPreset1280x720;

Then you must create the input and add it to the session in order to get images from your device camera:

AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];

    NSError *error = nil;
    AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:device error:&error];

    if (!input) {
        NSLog(@"Couldn't create video capture device");
    }
    [session addInput:input];

Then you make use of AVCaptureVideoPreviewLayer to present in a Layer the images from your device camera:

AVCaptureVideoPreviewLayer *newCaptureVideoPreviewLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:session];

Finally you just need to set the frame (portion of UI you need) of that specific layer and add it to the desired view and start the session capture.