mx::MXCapture Class Reference

OpenCV video capture source that renders via an OpenGL sprite. More...

#include <gl_cv.hpp>

Collaboration diagram for mx::MXCapture:

Public Member Functions
	MXCapture ()=default
	Default constructor.
	~MXCapture ()=default
	Destructor.
MXCapture &	operator= (const MXCapture &)=delete
MXCapture &	operator= (MXCapture &&)=delete
	MXCapture (const MXCapture &)=delete
	MXCapture (MXCapture &&)=delete
bool	open (const std::string &filename)
	Open a video file for capture.
bool	open (int id, int mode=0)
	Open a camera device for capture.
void	close ()
	Close the video source.
bool	is_open () const
	Check whether the capture source is open.
bool	createImage (gl::GLWindow *window, size_t width, size_t height, const std::string &vert, const std::string &frag)
	Create the backing sprite/texture for displaying frames.
gl::GLSprite *	getSprite ()
	Access the internal sprite.
void	draw (int x, int y, int width, int height)
	Draw the most recently captured frame.
void	draw (int x, int y)
	Draw using the sprite's native dimensions.
bool	reload (const std::string &vert, const std::string &frag)
	Replace the shader pair without reopening the source.
bool	read ()
	Grab and decode the next frame from the source.
bool	read (cv::Mat &frame)
	Grab and decode the next frame into a cv::Mat.
void	set (unsigned int option, double value)
	Set a VideoCapture property.
double	get (unsigned int option)
	Query a VideoCapture property.
	MXCapture ()=default
	Default constructor.
	~MXCapture ()=default
	Destructor.
MXCapture &	operator= (const MXCapture &)=delete
MXCapture &	operator= (MXCapture &&)=delete
	MXCapture (const MXCapture &)=delete
	MXCapture (MXCapture &&)=delete
bool	open (const std::string &filename)
	Open a video file.
bool	open (int id, int mode=0)
	Open a camera device.
void	close ()
	Close the capture device.
bool	is_open () const
	Check whether the capture device is open.
bool	createImage (VKWindow *window, size_t width, size_t height, const std::string &vert, const std::string &frag)
	Allocate the VKSprite and upload the initial texture.
VKSprite *	getSprite ()
	Access the backing sprite.
void	draw (int x, int y, int width, int height)
	Draw the current frame at a specified position and size.
void	draw (int x, int y)
	Draw using the sprite's native dimensions.
bool	reload (size_t width, size_t height, const std::string &vert, const std::string &frag)
	Replace the vertex/fragment shaders.
bool	read ()
	Capture and upload the next video frame.
bool	read (cv::Mat &frame)
	Capture the next frame into a cv::Mat.
void	set (unsigned int option, double value)
	Set a VideoCapture property.
double	get (unsigned int option)
	Query a VideoCapture property.

Private Attributes
gl::GLSprite	sprite
	Rendering sprite.
std::unique_ptr< gl::ShaderProgram >	shader
	Active shader program.
gl::GLWindow *	window = nullptr
	Parent GL window.
cv::VideoCapture	cap
	OpenCV capture device.
cv::Mat	frame
	Most recent decoded frame.
VKSprite *	sprite = nullptr
	Backing Vulkan sprite.

Detailed Description

OpenCV video capture source that renders via an OpenGL sprite.

Vulkan OpenCV video capture source.

Opens a video file or camera device, reads frames frame-by-frame, and uploads each frame to a gl::GLSprite texture for display inside a gl::GLWindow with a custom GLSL shader.

Opens a video file or camera, decodes frames, and uploads them to a VKSprite texture for Vulkan-accelerated rendering inside a VKWindow.

Definition at line 26 of file gl_cv.hpp.

Constructor & Destructor Documentation

MXCapture() [1/6]

mx::MXCapture::MXCapture ( )

default

Default constructor.

Referenced by MXCapture(), MXCapture(), operator=(), and operator=().

~MXCapture() [1/2]

mx::MXCapture::~MXCapture ( )

default

Destructor.

MXCapture() [2/6]

mx::MXCapture::MXCapture ( const MXCapture & )

delete

References MXCapture().

MXCapture() [3/6]

mx::MXCapture::MXCapture ( MXCapture && )

delete

References MXCapture().

MXCapture() [4/6]

mx::MXCapture::MXCapture ( )

default

Default constructor.

~MXCapture() [2/2]

mx::MXCapture::~MXCapture ( )

default

Destructor.

MXCapture() [5/6]

mx::MXCapture::MXCapture ( const MXCapture & )

delete

References MXCapture().

MXCapture() [6/6]

mx::MXCapture::MXCapture ( MXCapture && )

delete

References MXCapture().

Member Function Documentation

close() [1/2]

void mx::MXCapture::close

(

)

Close the video source.

Definition at line 25 of file gl_cv.cpp.

References cap.

close() [2/2]

void mx::MXCapture::close

(

)

Close the capture device.

createImage() [1/2]

bool mx::MXCapture::createImage	(	gl::GLWindow *	window,
		size_t	width,
		size_t	height,
		const std::string &	vert,
		const std::string &	frag )

Create the backing sprite/texture for displaying frames.

Parameters

window	OpenGL window context.
width	Frame display width.
height	Frame display height.
vert	Path to the vertex shader GLSL file.
frag	Path to the fragment shader GLSL file.

Returns

true on success.

Definition at line 29 of file gl_cv.cpp.

References gl::createTexture(), shader, sprite, and window.

createImage() [2/2]

bool mx::MXCapture::createImage	(	VKWindow *	window,
		size_t	width,
		size_t	height,
		const std::string &	vert,
		const std::string &	frag )

Allocate the VKSprite and upload the initial texture.

Parameters

window	Parent VKWindow.
width	Display width.
height	Display height.
vert	Vertex shader path.
frag	Fragment shader path.

Returns

true on success.

Definition at line 28 of file vk_cv.cpp.

References sprite, and window.

draw() [1/4]

void mx::MXCapture::draw	(	int	x,
		int	y )

Draw using the sprite's native dimensions.

Parameters

x	Destination X position.
y	Destination Y position.

Definition at line 74 of file gl_cv.cpp.

References sprite, and window.

draw() [2/4]

void mx::MXCapture::draw	(	int	x,
		int	y )

Draw using the sprite's native dimensions.

Parameters

x	Destination X.
y	Destination Y.

draw() [3/4]

void mx::MXCapture::draw	(	int	x,
		int	y,
		int	width,
		int	height )

Draw the most recently captured frame.

Parameters

x	Destination X position.
y	Destination Y position.
width	Display width.
height	Display height.

Definition at line 67 of file gl_cv.cpp.

References sprite, and window.

draw() [4/4]

void mx::MXCapture::draw	(	int	x,
		int	y,
		int	width,
		int	height )

Draw the current frame at a specified position and size.

Parameters

x	Width destination X.
y	Width destination Y.
width	Display width.
height	Display height.

get() [1/2]

double mx::MXCapture::get

(

unsigned int

option

)

Query a VideoCapture property.

Parameters

option

cv::VideoCaptureProperties constant.

Returns

Current property value.

Definition at line 85 of file gl_cv.cpp.

References cap.

get() [2/2]

double mx::MXCapture::get

(

unsigned int

option

)

Query a VideoCapture property.

Parameters

option

cv::VideoCaptureProperties constant.

Returns

Current value.

getSprite() [1/2]

gl::GLSprite * mx::MXCapture::getSprite ( )

inline

Access the internal sprite.

Returns

Pointer to the backing gl::GLSprite.

Definition at line 76 of file gl_cv.hpp.

References sprite.

getSprite() [2/2]

VKSprite * mx::MXCapture::getSprite ( )

inline

Access the backing sprite.

Returns

Pointer to the VKSprite.

Definition at line 75 of file vk_cv.hpp.

References sprite.

is_open() [1/2]

bool mx::MXCapture::is_open ( ) const

inline

Check whether the capture source is open.

Returns

true if the VideoCapture is opened.

Definition at line 59 of file gl_cv.hpp.

References cap.

is_open() [2/2]

bool mx::MXCapture::is_open ( ) const

inline

Check whether the capture device is open.

Returns

true if the VideoCapture is opened.

Definition at line 58 of file vk_cv.hpp.

References cap.

open() [1/4]

bool mx::MXCapture::open

(

const std::string &

filename

)

Open a video file for capture.

Parameters

filename

Path to the video file.

Returns

true on success.

Definition at line 11 of file gl_cv.cpp.

References cap.

open() [2/4]

bool mx::MXCapture::open

(

const std::string &

filename

)

Open a video file.

Parameters

filename

Path to the video file.

Returns

true on success.

open() [3/4]

bool mx::MXCapture::open	(	int	id,
		int	mode = 0 )

Open a camera device for capture.

Parameters

id	Camera device index.
mode	Optional backend hint (0 = auto).

Returns

true on success.

Definition at line 15 of file gl_cv.cpp.

References cap.

open() [4/4]

bool mx::MXCapture::open	(	int	id,
		int	mode = 0 )

Open a camera device.

Parameters

id	Camera index.
mode	Backend hint (0 = auto).

Returns

true on success.

operator=() [1/4]

MXCapture & mx::MXCapture::operator= ( const MXCapture & )

delete

References MXCapture().

operator=() [2/4]

MXCapture & mx::MXCapture::operator= ( const MXCapture & )

delete

References MXCapture().

operator=() [3/4]

MXCapture & mx::MXCapture::operator= ( MXCapture && )

delete

References MXCapture().

operator=() [4/4]

MXCapture & mx::MXCapture::operator= ( MXCapture && )

delete

References MXCapture().

read() [1/4]

bool mx::MXCapture::read

(

)

Grab and decode the next frame from the source.

Returns

true if a new frame was available.

Definition at line 56 of file gl_cv.cpp.

References cap, frame, and sprite.

read() [2/4]

bool mx::MXCapture::read

(

)

Capture and upload the next video frame.

Returns

true if a frame was available.

read() [3/4]

bool mx::MXCapture::read

(

cv::Mat &

frame

)

Grab and decode the next frame into a cv::Mat.

Parameters

frame

Output matrix.

Returns

true if a new frame was available.

Definition at line 52 of file gl_cv.cpp.

References cap, and frame.

read() [4/4]

bool mx::MXCapture::read

(

cv::Mat &

frame

)

Capture the next frame into a cv::Mat.

Parameters

frame

Output matrix.

Returns

true if a frame was available.

References frame.

reload() [1/2]

bool mx::MXCapture::reload	(	const std::string &	vert,
		const std::string &	frag )

Replace the shader pair without reopening the source.

Parameters

vert	New vertex shader path.
frag	New fragment shader path.

Returns

true on success.

Definition at line 44 of file gl_cv.cpp.

References shader.

reload() [2/2]

bool mx::MXCapture::reload	(	size_t	width,
		size_t	height,
		const std::string &	vert,
		const std::string &	frag )

Replace the vertex/fragment shaders.

Parameters

width	Display width.
height	Display height.
vert	New vertex shader path.
frag	New fragment shader path.

Returns

true on success.

Definition at line 40 of file vk_cv.cpp.

References sprite.

set() [1/2]

void mx::MXCapture::set	(	unsigned int	option,
		double	value )

Set a VideoCapture property.

Parameters

option	cv::VideoCaptureProperties constant.
value	Desired value.

Definition at line 81 of file gl_cv.cpp.

References cap.

set() [2/2]

void mx::MXCapture::set	(	unsigned int	option,
		double	value )

Set a VideoCapture property.

Parameters

option	cv::VideoCaptureProperties constant.
value	Desired value.

Member Data Documentation

cap

cv::VideoCapture mx::MXCapture::cap

private

OpenCV capture device.

Definition at line 132 of file gl_cv.hpp.

Referenced by close(), get(), is_open(), open(), open(), read(), read(), and set().

frame

cv::Mat mx::MXCapture::frame

private

Most recent decoded frame.

Definition at line 133 of file gl_cv.hpp.

Referenced by read(), and read().

shader

std::unique_ptr<gl::ShaderProgram> mx::MXCapture::shader

private

Active shader program.

Definition at line 130 of file gl_cv.hpp.

Referenced by createImage(), and reload().

sprite [1/2]

gl::GLSprite mx::MXCapture::sprite

private

Rendering sprite.

Definition at line 129 of file gl_cv.hpp.

Referenced by createImage(), createImage(), draw(), draw(), getSprite(), read(), and reload().

sprite [2/2]

VKSprite* mx::MXCapture::sprite = nullptr

private

Backing Vulkan sprite.

Definition at line 130 of file vk_cv.hpp.

window

gl::GLWindow* mx::MXCapture::window = nullptr

private

Parent GL window.

Definition at line 131 of file gl_cv.hpp.

Referenced by createImage(), createImage(), draw(), and draw().

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

• gl_cv.hpp
• vk_cv.hpp
• gl_cv.cpp
• vk_cv.cpp