HVTCameraDelegate Protocol Reference

Conforms to NSObject
Declared in HVTCamera.h

Overview

The HVTCameraDelegate protocol defines delegate methods you should implement in order to get updates from an HVTCamera instance about the running state, recording status, handle errors and update the UI.

All the delegate methods are invoked in the main thread.

Interface Delegate Method

– hvtCamera:didUpdateParams: required method

Implement this method to be notified of the updated device angle and computed scale factors in order to adjust your interface elements (i.e. rotate your UI elements).

- (void)hvtCamera:(HVTCamera *)hvtCamera didUpdateParams:(HVTParams)params

Parameters

hvtCamera

The HVTCamera object calling the delegate method.
params

The angle (physical yaw) of the device in rads and scale values.

Discussion

The angle represents the yaw of the device (in the real world) at the time the latest video frame was received by the device’s camera.

The scale represents the scale that has to be applied to the frame depending on the active levelerCropMode and the angle of the device.

You may want to rotate your UI elements to match the attached HVTView(s) appearence as illustrated in the following code fragment:

- (void)hvtCamera:(HVTCamera *)hvtCamera didUpdateParams:(HVTParams)params
{
    [_uiElement setTransform:CGAffineTransformMakeRotation(params.angle)];
}

The calling frequency matches the frame rate of the HVTCamera instance.

Declared In

HVTCamera.h

Running State Delegate Method

– hvtCameraDidStartRunning:

Called when HVTcamera starts running.

- (void)hvtCameraDidStartRunning:(HVTCamera *)hvtCamera

Parameters

hvtCamera

The HVTCamera object calling the delegate method.

Declared In

HVTCamera.h

– hvtCamera:didStopRunningWithError:

Called when HVTcamera stops running due to an error.

- (void)hvtCamera:(HVTCamera *)hvtCamera didStopRunningWithError:(NSError *)error

Parameters

hvtCamera

The HVTCamera object calling the delegate method.
error

The error occured.

Declared In

HVTCamera.h

Recording Delegate Methods

– hvtCameraRecordingDidStart:

Called when video recording has begun.

- (void)hvtCameraRecordingDidStart:(HVTCamera *)hvtCamera

Parameters

hvtCamera

The HVTCamera object calling the delegate method.

Declared In

HVTCamera.h

– hvtCamera:didUpdateRecordingDuration:

Implement this method to get the updated recording duration in order to update duration counters in your interface.

- (void)hvtCamera:(HVTCamera *)hvtCamera didUpdateRecordingDuration:(NSTimeInterval)duration

Parameters

hvtCamera

The HVTCamera object calling the delegate method.
duration

The video duration up until this point as a NSTimeInterval variable.

Discussion

This method is called for every recorded frame when recording a video.

Declared In

HVTCamera.h

– hvtCameraRecordingWillStop:

Called when video recording is going to stop.

- (void)hvtCameraRecordingWillStop:(HVTCamera *)hvtCamera

Parameters

hvtCamera

The HVTCamera object calling the delegate method.

Declared In

HVTCamera.h

– hvtCamera:didStopRecordingWithMetadata:

Called when video recording has stopped successfully. You can access the recorded video’s properties through the metadata NSDictionary.

- (void)hvtCamera:(HVTCamera *)hvtCamera didStopRecordingWithMetadata:(NSDictionary *)metadata

Parameters

hvtCamera

The HVTCamera object calling the delegate method.
metadata

The NSDictionary containing information of the recorded video.

Declared In

HVTCamera.h

– hvtCamera:recordingDidFailWithError:

Called when video recording has stopped due to an error.

- (void)hvtCamera:(HVTCamera *)hvtCamera recordingDidFailWithError:(NSError *)error

Parameters

hvtCamera

The HVTCamera object calling the delegate method.
error

The error occured

Declared In

HVTCamera.h

Photo Capturing Delegate Methods

– hvtCamera:didCapturePhotoData:metadata:

Called when a photo has been captured

- (void)hvtCamera:(HVTCamera *)hvtCamera didCapturePhotoData:(NSData *)photo metadata:(NSDictionary *)metadata

Parameters

hvtCamera

The HVTCamera object calling the delegate method.
photo

The photo captured as NSData (JPEG representation)
metadata

The photo metadata (already passed inside the NSData structure)

Declared In

HVTCamera.h

– hvtCamera:didCapturePhotoImageRef:metadata:

Called when a photo has been captured

- (void)hvtCamera:(HVTCamera *)hvtCamera didCapturePhotoImageRef:(CGImageRef)photo metadata:(NSDictionary *)metadata

Parameters

hvtCamera

The HVTCamera object calling the delegate method.
photo

The photo captured as CGImageRef
metadata

The photo metadata

Declared In

HVTCamera.h

– hvtCamera:photoCapturingDidFailWithError:

Called when photo capturing has not been completed successfully due to an error.

- (void)hvtCamera:(HVTCamera *)hvtCamera photoCapturingDidFailWithError:(NSError *)error

Parameters

hvtCamera

The HVTCamera object calling the delegate method.
error

The error occured

Declared In

HVTCamera.h