ARCameraStream Class Reference

#import <ARCameraStream.h>

Inherits NSObject, and <AVCaptureVideoDataOutputSampleBufferDelegate>.

Instance Methods
(ARColour *)	- averageColourFromData:withChannels:downsamplingWidth:height:
(void)	- initialise
(void)	- deinitialise
(void)	- start
(void)	- stop
(void)	- addDelegate:
(void)	- removeDelegate:
(void)	- removeDelegates

Class Methods
(ARCameraStream *)	+ getInstance

Properties
float	width
float	height
float	padding
ARTexture *	cameraTexture
ARTexture *	cameraTextureY
ARTexture *	cameraTextureUV
NSArray *	delegates

Detailed Description

The ARCameraStream is a singleton manager class for handling the camera stream. It can be used to gain access to the background camera texture or to provide camera events.

Method Documentation

addDelegate:

- (void) addDelegate:

(id<ARCameraStreamEvent>)

delegate

Parameters

delegate

The delegate to add. Add a delegate for camera update event notifications.

averageColourFromData:withChannels:downsamplingWidth:height:

- (ARColour *) averageColourFromData:		(NSData *)	data
withChannels:		(int)	channels
downsamplingWidth:		(int)	width
height:		(int)	height

Returns the average colour of an image expressed as a byte array. The image will be downsized before computation of the average. Smaller images will compute faster at the expense of accuracy. It is recommended to reduce image size as much as possible.

Example of use:

ARCameraStream *cameraStream = [ARCameraStream getInstance];
ARColour *averageColour = [cameraStream averageColourFromData:cameraStream.cameraTexture._rawImage withChannels:3 downSamplingWidth:64 height:64];

Parameters

data	NSData object containing the image data.
channels	The number of channels contained within the image data. For example, RGB data would contain 3 channels.
width	The width, in pixels, to which the image will be scaled before computing the average.
height	The height, in pixels, to which the image will be scaled before computing the average.

Returns

Average colour of the image as an ARColour object.

deinitialise

- (void) deinitialise

Deinitialise the camera. This is handled automatically when your view controller is a subclass of the ARCameraViewController.

Example of use:

[[ARCameraStream getInstance] deinitialise];

getInstance

+ (ARCameraStream *) getInstance

Gets the instance of the camera stream singleton.

Example of use:

ARCameraStream *cameraStream = [ARCameraStream getInstance];

Returns

The singleton instance.

initialise

- (void) initialise

Initialise the camera. This is handled automatically when your view controller is a subclass of the ARCameraViewController. When the ARCameraStream instance is initialised, it performs the following: Creates a reference to the renderer's texture cache. Creates a reference to a valid camera device. Sets up a new capture session with a valid camera input device. Sets the camera to "continous autofocus" mode, if supported.

Example of use:

[[ARCameraStream getInstance] initialise];

removeDelegate:

- (void) removeDelegate:

(id<ARCameraStreamEvent>)

delegate

Parameters

delegate

The delegate to remove. Remove a delegate from camera update event notifications.

removeDelegates

- (void) removeDelegates

Removes all ARCameraStreamEvent delegates currently associated with this singleton.

start

- (void) start

Start the camera stream. This is handled automatically when your view controller is a subclass of the ARCameraViewController.

Example of use:

[[ARCameraStream getInstance] start];

stop

- (void) stop

Stop the camera stream. This is handled automatically when your view controller is a subclass of the ARCameraViewController.

Example of use:

[[ARCameraStream getInstance] stop];

Property Documentation

cameraTexture

- (ARTexture*) cameraTexture

readwritenonatomicassign

The full-colour camera texture, including all 3 channels.

cameraTextureUV

- (ARTexture*) cameraTextureUV

readwritenonatomicassign

Camera chroma texture. This texture includes both the U and V channels, which contain the colour information of the image. The is not a full colour texture, as the U and V channels are colour differences that depend on the luminance values of the Y channel to be correct.

cameraTextureY

- (ARTexture*) cameraTextureY

readwritenonatomicassign

Camera luma texture. This texture only includes the Y(Luma) colour channel, meaning it will appear as a black-and-white image.

delegates

- (NSArray*) delegates

readwritenonatomicassign

Array containing all ARCameraStreamEvent delegates that have been added to this singleton.

height

- (float) height

readwritenonatomicassign

The height of the camera image, in pixels.

padding

- (float) padding

readwritenonatomicassign

The thickness of padding around the camera image, in pixels. This effectively creates a border around the camera stream.

width

- (float) width

readwritenonatomicassign

The width of the camera image, in pixels.

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The documentation for this class was generated from the following files:

• ARCameraStream.h
• ARCameraStream.mm