cv::Rect_< _Tp > Class Template Reference

Template class for 2D rectangles. More...

#include "types.hpp"

Public Types
typedef _Tp	value_type

Public Member Functions
	Rect_ ()
	various constructors More...
	Rect_ (_Tp _x, _Tp _y, _Tp _width, _Tp _height)
	Rect_ (const Rect_ &r)
	Rect_ (const Point_< _Tp > &org, const Size_< _Tp > &sz)
	Rect_ (const Point_< _Tp > &pt1, const Point_< _Tp > &pt2)
_Tp	area () const
	area (width*height) of the rectangle More...
Point_< _Tp >	br () const
	the bottom-right corner More...
bool	contains (const Point_< _Tp > &pt) const
	checks whether the rectangle contains the point More...
template<typename _Tp2 >
	operator Rect_< _Tp2 > () const
	conversion to another data type More...
Rect_ &	operator= (const Rect_ &r)
Size_< _Tp >	size () const
	size (width, height) of the rectangle More...
Point_< _Tp >	tl () const
	the top-left corner More...

Public Attributes
_Tp	height
_Tp	width
_Tp	x
_Tp	y

Detailed Description

template<typename _Tp>
class cv::Rect_< _Tp >

Template class for 2D rectangles.

described by the following parameters:

• Coordinates of the top-left corner. This is a default interpretation of Rect_::x and Rect_::y in OpenCV. Though, in your algorithms you may count x and y from the bottom-left corner.
• Rectangle width and height.

OpenCV typically assumes that the top and left boundary of the rectangle are inclusive, while the right and bottom boundaries are not. For example, the method Rect_::contains returns true if

\[x \leq pt.x < x+width, y \leq pt.y < y+height\]

Virtually every loop over an image ROI in OpenCV (where ROI is specified by Rect_<int> ) is implemented as:

for(int y = roi.y; y < roi.y + roi.height; y++)
    for(int x = roi.x; x < roi.x + roi.width; x++)
    {
        // ...
    }

In addition to the class members, the following operations on rectangles are implemented:

• \(\texttt{rect} = \texttt{rect} \pm \texttt{point}\) (shifting a rectangle by a certain offset)
• \(\texttt{rect} = \texttt{rect} \pm \texttt{size}\) (expanding or shrinking a rectangle by a certain amount)
• rect += point, rect -= point, rect += size, rect -= size (augmenting operations)
• rect = rect1 & rect2 (rectangle intersection)
• rect = rect1 | rect2 (minimum area rectangle containing rect1 and rect2 )
• rect &= rect1, rect |= rect1 (and the corresponding augmenting operations)
• rect == rect1, rect != rect1 (rectangle comparison)

This is an example how the partial ordering on rectangles can be established (rect1 \(\subseteq\) rect2):

template<typename _Tp> inline bool
operator <= (const Rect_<_Tp>& r1, const Rect_<_Tp>& r2)
{
    return (r1 & r2) == r1;
}

For your convenience, the Rect_<> alias is available: cv::Rect

Examples:

ffilldemo.cpp, and grabcut.cpp.

Member Typedef Documentation

template<typename _Tp>

typedef _Tp cv::Rect_< _Tp >::value_type

Constructor & Destructor Documentation

template<typename _Tp>

cv::Rect_< _Tp >::Rect_

(

)

various constructors

template<typename _Tp>

cv::Rect_< _Tp >::Rect_	(	_Tp	_x,
		_Tp	_y,
		_Tp	_width,
		_Tp	_height
	)

template<typename _Tp>

cv::Rect_< _Tp >::Rect_

(

const Rect_< _Tp > &

r

)

template<typename _Tp>

cv::Rect_< _Tp >::Rect_	(	const Point_< _Tp > &	org,
		const Size_< _Tp > &	sz
	)

template<typename _Tp>

cv::Rect_< _Tp >::Rect_	(	const Point_< _Tp > &	pt1,
		const Point_< _Tp > &	pt2
	)

Member Function Documentation

template<typename _Tp>

_Tp cv::Rect_< _Tp >::area

(

)

const

area (width*height) of the rectangle

template<typename _Tp>

Point_<_Tp> cv::Rect_< _Tp >::br

(

)

const

the bottom-right corner

template<typename _Tp>

bool cv::Rect_< _Tp >::contains

(

const Point_< _Tp > &

pt

)

const

checks whether the rectangle contains the point

template<typename _Tp>

template<typename _Tp2 >

cv::Rect_< _Tp >::operator Rect_< _Tp2 >

(

)

const

conversion to another data type

template<typename _Tp>

Rect_& cv::Rect_< _Tp >::operator=

(

const Rect_< _Tp > &

r

)

template<typename _Tp>

Size_<_Tp> cv::Rect_< _Tp >::size

(

)

const

size (width, height) of the rectangle

template<typename _Tp>

Point_<_Tp> cv::Rect_< _Tp >::tl

(

)

const

the top-left corner

Member Data Documentation

template<typename _Tp>

_Tp cv::Rect_< _Tp >::height

template<typename _Tp>

_Tp cv::Rect_< _Tp >::width

template<typename _Tp>

_Tp cv::Rect_< _Tp >::x

template<typename _Tp>

_Tp cv::Rect_< _Tp >::y

---

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

• core/include/opencv2/core/types.hpp