cv::MatExpr Class Reference

Matrix expression representation. More...

#include <opencv2/core/mat.hpp>

Public Member Functions
	MatExpr ()
	MatExpr (const Mat &m)
	MatExpr (const MatOp *_op, int _flags, const Mat &_a=Mat(), const Mat &_b=Mat(), const Mat &_c=Mat(), double _alpha=1, double _beta=1, const Scalar &_s=Scalar())
MatExpr	col (int x) const
Mat	cross (const Mat &m) const
MatExpr	diag (int d=0) const
double	dot (const Mat &m) const
MatExpr	inv (int method=DECOMP_LU) const
MatExpr	mul (const MatExpr &e, double scale=1) const
MatExpr	mul (const Mat &m, double scale=1) const
	operator Mat () const
template<typename _Tp >
	operator Mat_< _Tp > () const
MatExpr	operator() (const Range &rowRange, const Range &colRange) const
MatExpr	operator() (const Rect &roi) const
MatExpr	row (int y) const
Size	size () const
MatExpr	t () const
int	type () const

Public Attributes
Mat	a
double	alpha
Mat	b
double	beta
Mat	c
int	flags
const MatOp *	op
Scalar	s

Related Functions
(Note that these are not member functions.)
MatExpr	operator+ (const Mat &a, const Mat &b)
MatExpr	operator+ (const Mat &a, const Scalar &s)
MatExpr	operator+ (const Scalar &s, const Mat &a)
MatExpr	operator+ (const MatExpr &e, const Mat &m)
MatExpr	operator+ (const Mat &m, const MatExpr &e)
MatExpr	operator+ (const MatExpr &e, const Scalar &s)
MatExpr	operator+ (const Scalar &s, const MatExpr &e)
MatExpr	operator+ (const MatExpr &e1, const MatExpr &e2)
template<typename _Tp , int m, int n>
static MatExpr	operator+ (const Mat &a, const Matx< _Tp, m, n > &b)
template<typename _Tp , int m, int n>
static MatExpr	operator+ (const Matx< _Tp, m, n > &a, const Mat &b)
MatExpr	operator- (const Mat &a, const Mat &b)
MatExpr	operator- (const Mat &a, const Scalar &s)
MatExpr	operator- (const Scalar &s, const Mat &a)
MatExpr	operator- (const MatExpr &e, const Mat &m)
MatExpr	operator- (const Mat &m, const MatExpr &e)
MatExpr	operator- (const MatExpr &e, const Scalar &s)
MatExpr	operator- (const Scalar &s, const MatExpr &e)
MatExpr	operator- (const MatExpr &e1, const MatExpr &e2)
template<typename _Tp , int m, int n>
static MatExpr	operator- (const Mat &a, const Matx< _Tp, m, n > &b)
template<typename _Tp , int m, int n>
static MatExpr	operator- (const Matx< _Tp, m, n > &a, const Mat &b)
MatExpr	operator- (const Mat &m)
MatExpr	operator- (const MatExpr &e)
MatExpr	operator* (const Mat &a, const Mat &b)
MatExpr	operator* (const Mat &a, double s)
MatExpr	operator* (double s, const Mat &a)
MatExpr	operator* (const MatExpr &e, const Mat &m)
MatExpr	operator* (const Mat &m, const MatExpr &e)
MatExpr	operator* (const MatExpr &e, double s)
MatExpr	operator* (double s, const MatExpr &e)
MatExpr	operator* (const MatExpr &e1, const MatExpr &e2)
template<typename _Tp , int m, int n>
static MatExpr	operator* (const Mat &a, const Matx< _Tp, m, n > &b)
template<typename _Tp , int m, int n>
static MatExpr	operator* (const Matx< _Tp, m, n > &a, const Mat &b)
MatExpr	operator/ (const Mat &a, const Mat &b)
MatExpr	operator/ (const Mat &a, double s)
MatExpr	operator/ (double s, const Mat &a)
MatExpr	operator/ (const MatExpr &e, const Mat &m)
MatExpr	operator/ (const Mat &m, const MatExpr &e)
MatExpr	operator/ (const MatExpr &e, double s)
MatExpr	operator/ (double s, const MatExpr &e)
MatExpr	operator/ (const MatExpr &e1, const MatExpr &e2)
template<typename _Tp , int m, int n>
static MatExpr	operator/ (const Mat &a, const Matx< _Tp, m, n > &b)
template<typename _Tp , int m, int n>
static MatExpr	operator/ (const Matx< _Tp, m, n > &a, const Mat &b)
MatExpr	operator< (const Mat &a, const Mat &b)
MatExpr	operator< (const Mat &a, double s)
MatExpr	operator< (double s, const Mat &a)
template<typename _Tp , int m, int n>
static MatExpr	operator< (const Mat &a, const Matx< _Tp, m, n > &b)
template<typename _Tp , int m, int n>
static MatExpr	operator< (const Matx< _Tp, m, n > &a, const Mat &b)
MatExpr	operator<= (const Mat &a, const Mat &b)
MatExpr	operator<= (const Mat &a, double s)
MatExpr	operator<= (double s, const Mat &a)
template<typename _Tp , int m, int n>
static MatExpr	operator<= (const Mat &a, const Matx< _Tp, m, n > &b)
template<typename _Tp , int m, int n>
static MatExpr	operator<= (const Matx< _Tp, m, n > &a, const Mat &b)
MatExpr	operator== (const Mat &a, const Mat &b)
MatExpr	operator== (const Mat &a, double s)
MatExpr	operator== (double s, const Mat &a)
template<typename _Tp , int m, int n>
static MatExpr	operator== (const Mat &a, const Matx< _Tp, m, n > &b)
template<typename _Tp , int m, int n>
static MatExpr	operator== (const Matx< _Tp, m, n > &a, const Mat &b)
MatExpr	operator!= (const Mat &a, const Mat &b)
MatExpr	operator!= (const Mat &a, double s)
MatExpr	operator!= (double s, const Mat &a)
template<typename _Tp , int m, int n>
static MatExpr	operator!= (const Mat &a, const Matx< _Tp, m, n > &b)
template<typename _Tp , int m, int n>
static MatExpr	operator!= (const Matx< _Tp, m, n > &a, const Mat &b)
MatExpr	operator>= (const Mat &a, const Mat &b)
MatExpr	operator>= (const Mat &a, double s)
MatExpr	operator>= (double s, const Mat &a)
template<typename _Tp , int m, int n>
static MatExpr	operator>= (const Mat &a, const Matx< _Tp, m, n > &b)
template<typename _Tp , int m, int n>
static MatExpr	operator>= (const Matx< _Tp, m, n > &a, const Mat &b)
MatExpr	operator> (const Mat &a, const Mat &b)
MatExpr	operator> (const Mat &a, double s)
MatExpr	operator> (double s, const Mat &a)
template<typename _Tp , int m, int n>
static MatExpr	operator> (const Mat &a, const Matx< _Tp, m, n > &b)
template<typename _Tp , int m, int n>
static MatExpr	operator> (const Matx< _Tp, m, n > &a, const Mat &b)
MatExpr	operator& (const Mat &a, const Mat &b)
MatExpr	operator& (const Mat &a, const Scalar &s)
MatExpr	operator& (const Scalar &s, const Mat &a)
template<typename _Tp , int m, int n>
static MatExpr	operator& (const Mat &a, const Matx< _Tp, m, n > &b)
template<typename _Tp , int m, int n>
static MatExpr	operator& (const Matx< _Tp, m, n > &a, const Mat &b)
MatExpr	operator| (const Mat &a, const Mat &b)
MatExpr	operator| (const Mat &a, const Scalar &s)
MatExpr	operator| (const Scalar &s, const Mat &a)
template<typename _Tp , int m, int n>
static MatExpr	operator| (const Mat &a, const Matx< _Tp, m, n > &b)
template<typename _Tp , int m, int n>
static MatExpr	operator| (const Matx< _Tp, m, n > &a, const Mat &b)
MatExpr	operator^ (const Mat &a, const Mat &b)
MatExpr	operator^ (const Mat &a, const Scalar &s)
MatExpr	operator^ (const Scalar &s, const Mat &a)
template<typename _Tp , int m, int n>
static MatExpr	operator^ (const Mat &a, const Matx< _Tp, m, n > &b)
template<typename _Tp , int m, int n>
static MatExpr	operator^ (const Matx< _Tp, m, n > &a, const Mat &b)
MatExpr	operator~ (const Mat &m)
MatExpr	min (const Mat &a, const Mat &b)
MatExpr	min (const Mat &a, double s)
MatExpr	min (double s, const Mat &a)
template<typename _Tp , int m, int n>
static MatExpr	min (const Mat &a, const Matx< _Tp, m, n > &b)
template<typename _Tp , int m, int n>
static MatExpr	min (const Matx< _Tp, m, n > &a, const Mat &b)
MatExpr	max (const Mat &a, const Mat &b)
MatExpr	max (const Mat &a, double s)
MatExpr	max (double s, const Mat &a)
template<typename _Tp , int m, int n>
static MatExpr	max (const Mat &a, const Matx< _Tp, m, n > &b)
template<typename _Tp , int m, int n>
static MatExpr	max (const Matx< _Tp, m, n > &a, const Mat &b)
MatExpr	abs (const Mat &m)
	Calculates an absolute value of each matrix element.
MatExpr	abs (const MatExpr &e)

Detailed Description

Matrix expression representation.

This is a list of implemented matrix operations that can be combined in arbitrary complex expressions (here A, B stand for matrices ( Mat ), s for a scalar ( Scalar ), alpha for a real-valued scalar ( double )):

• Addition, subtraction, negation: A+B, A-B, A+s, A-s, s+A, s-A, -A
• Scaling: A*alpha
• Per-element multiplication and division: A.mul(B), A/B, alpha/A
• Matrix multiplication: A*B
• Transposition: A.t() (means A^T)
• Matrix inversion and pseudo-inversion, solving linear systems and least-squares problems: A.inv([method]) (~ A<sup>-1</sup>), A.inv([method])*B (~ X: AX=B)
• Comparison: A cmpop B, A cmpop alpha, alpha cmpop A, where cmpop is one of >, >=, ==, !=, <=, <. The result of comparison is an 8-bit single channel mask whose elements are set to 255 (if the particular element or pair of elements satisfy the condition) or 0.
• Bitwise logical operations: A logicop B, A logicop s, s logicop A, ~A, where logicop is one of &, |, ^.
• Element-wise minimum and maximum: min(A, B), min(A, alpha), max(A, B), max(A, alpha)
• Element-wise absolute value: abs(A)
• Cross-product, dot-product: A.cross(B), A.dot(B)
• Any function of matrix or matrices and scalars that returns a matrix or a scalar, such as norm, mean, sum, countNonZero, trace, determinant, repeat, and others.
• Matrix initializers ( Mat::eye(), Mat::zeros(), Mat::ones() ), matrix comma-separated initializers, matrix constructors and operators that extract sub-matrices (see Mat description).
• Mat_<destination_type>() constructors to cast the result to the proper type.

  Note

  Comma-separated initializers and probably some other operations may require additional explicit Mat() or Mat_<T>() constructor calls to resolve a possible ambiguity.

  Here are examples of matrix expressions:

  // compute pseudo-inverse of A, equivalent to A.inv(DECOMP_SVD)
  SVD svd(A);
  Mat pinvA = svd.vt.t()*Mat::diag(1./svd.w)*svd.u.t();
  
  // compute the new vector of parameters in the Levenberg-Marquardt algorithm
  x -= (A.t()*A + lambda*Mat::eye(A.cols,A.cols,A.type())).inv(DECOMP_CHOLESKY)*(A.t()*err);
  
  // sharpen image using "unsharp mask" algorithm
  Mat blurred; double sigma = 1, threshold = 5, amount = 1;
  GaussianBlur(img, blurred, Size(), sigma, sigma);
  Mat lowContrastMask = abs(img - blurred) < threshold;
  Mat sharpened = img*(1+amount) + blurred*(-amount);
  img.copyTo(sharpened, lowContrastMask);

Constructor & Destructor Documentation

cv::MatExpr::MatExpr

(

)

cv::MatExpr::MatExpr ( const Mat &  m )

explicit

cv::MatExpr::MatExpr	(	const MatOp *	_op,
		int	_flags,
		const Mat &	_a = Mat(),
		const Mat &	_b = Mat(),
		const Mat &	_c = Mat(),
		double	_alpha = 1,
		double	_beta = 1,
		const Scalar &	_s = Scalar()
	)

Member Function Documentation

MatExpr cv::MatExpr::col

(

int

x

)

const

Mat cv::MatExpr::cross

(

const Mat &

m

)

const

MatExpr cv::MatExpr::diag

(

int

d = 0

)

const

double cv::MatExpr::dot

(

const Mat &

m

)

const

MatExpr cv::MatExpr::inv

(

int

method = DECOMP_LU

)

const

MatExpr cv::MatExpr::mul	(	const MatExpr &	e,
		double	scale = 1
	)		const

MatExpr cv::MatExpr::mul	(	const Mat &	m,
		double	scale = 1
	)		const

cv::MatExpr::operator Mat

(

)

const

template<typename _Tp >

cv::MatExpr::operator Mat_< _Tp >

(

)

const

MatExpr cv::MatExpr::operator()	(	const Range &	rowRange,
		const Range &	colRange
	)		const

MatExpr cv::MatExpr::operator()

(

const Rect &

roi

)

const

MatExpr cv::MatExpr::row

(

int

y

)

const

Size cv::MatExpr::size

(

)

const

MatExpr cv::MatExpr::t

(

)

const

Examples:

samples/cpp/tutorial_code/features2D/Homography/decompose_homography.cpp.

int cv::MatExpr::type

(

)

const

Friends And Related Function Documentation

MatExpr abs ( const Mat &  m )

related

Calculates an absolute value of each matrix element.

abs is a meta-function that is expanded to one of absdiff or convertScaleAbs forms:

• C = abs(A-B) is equivalent to absdiff(A, B, C)
• C = abs(A) is equivalent to absdiff(A, Scalar::all(0), C)
• C = Mat_<Vec<uchar,n> >(abs(A*alpha + beta)) is equivalent to convertScaleAbs(A, C, alpha, beta)

The output matrix has the same size and the same type as the input one except for the last case, where C is depth=CV_8U .

Parameters

m

matrix.

See Also

MatrixExpressions, absdiff, convertScaleAbs

MatExpr abs ( const MatExpr &  e )

related

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Parameters

e	matrix expression.

MatExpr max ( const Mat &  a, const Mat &  b  )

related

MatExpr max ( const Mat &  a, double  s  )

related

MatExpr max ( double  s, const Mat &  a  )

related

template<typename _Tp , int m, int n>

static MatExpr max ( const Mat &  a, const Matx< _Tp, m, n > &  b  )

related

template<typename _Tp , int m, int n>

static MatExpr max ( const Matx< _Tp, m, n > &  a, const Mat &  b  )

related

MatExpr min ( const Mat &  a, const Mat &  b  )

related

MatExpr min ( const Mat &  a, double  s  )

related

MatExpr min ( double  s, const Mat &  a  )

related

template<typename _Tp , int m, int n>

static MatExpr min ( const Mat &  a, const Matx< _Tp, m, n > &  b  )

related

template<typename _Tp , int m, int n>

static MatExpr min ( const Matx< _Tp, m, n > &  a, const Mat &  b  )

related

MatExpr operator!= ( const Mat &  a, const Mat &  b  )

related

MatExpr operator!= ( const Mat &  a, double  s  )

related

MatExpr operator!= ( double  s, const Mat &  a  )

related

template<typename _Tp , int m, int n>

static MatExpr operator!= ( const Mat &  a, const Matx< _Tp, m, n > &  b  )

related

template<typename _Tp , int m, int n>

static MatExpr operator!= ( const Matx< _Tp, m, n > &  a, const Mat &  b  )

related

MatExpr operator& ( const Mat &  a, const Mat &  b  )

related

MatExpr operator& ( const Mat &  a, const Scalar &  s  )

related

MatExpr operator& ( const Scalar &  s, const Mat &  a  )

related

template<typename _Tp , int m, int n>

static MatExpr operator& ( const Mat &  a, const Matx< _Tp, m, n > &  b  )

related

template<typename _Tp , int m, int n>

static MatExpr operator& ( const Matx< _Tp, m, n > &  a, const Mat &  b  )

related

MatExpr operator* ( const Mat &  a, const Mat &  b  )

related

MatExpr operator* ( const Mat &  a, double  s  )

related

MatExpr operator* ( double  s, const Mat &  a  )

related

MatExpr operator* ( const MatExpr &  e, const Mat &  m  )

related

MatExpr operator* ( const Mat &  m, const MatExpr &  e  )

related

MatExpr operator* ( const MatExpr &  e, double  s  )

related

MatExpr operator* ( double  s, const MatExpr &  e  )

related

MatExpr operator* ( const MatExpr &  e1, const MatExpr &  e2  )

related

template<typename _Tp , int m, int n>

static MatExpr operator* ( const Mat &  a, const Matx< _Tp, m, n > &  b  )

related

template<typename _Tp , int m, int n>

static MatExpr operator* ( const Matx< _Tp, m, n > &  a, const Mat &  b  )

related

MatExpr operator+ ( const Mat &  a, const Mat &  b  )

related

MatExpr operator+ ( const Mat &  a, const Scalar &  s  )

related

MatExpr operator+ ( const Scalar &  s, const Mat &  a  )

related

MatExpr operator+ ( const MatExpr &  e, const Mat &  m  )

related

MatExpr operator+ ( const Mat &  m, const MatExpr &  e  )

related

MatExpr operator+ ( const MatExpr &  e, const Scalar &  s  )

related

MatExpr operator+ ( const Scalar &  s, const MatExpr &  e  )

related

MatExpr operator+ ( const MatExpr &  e1, const MatExpr &  e2  )

related

template<typename _Tp , int m, int n>

static MatExpr operator+ ( const Mat &  a, const Matx< _Tp, m, n > &  b  )

related

template<typename _Tp , int m, int n>

static MatExpr operator+ ( const Matx< _Tp, m, n > &  a, const Mat &  b  )

related

MatExpr operator- ( const Mat &  a, const Mat &  b  )

related

MatExpr operator- ( const Mat &  a, const Scalar &  s  )

related

MatExpr operator- ( const Scalar &  s, const Mat &  a  )

related

MatExpr operator- ( const MatExpr &  e, const Mat &  m  )

related

MatExpr operator- ( const Mat &  m, const MatExpr &  e  )

related

MatExpr operator- ( const MatExpr &  e, const Scalar &  s  )

related

MatExpr operator- ( const Scalar &  s, const MatExpr &  e  )

related

MatExpr operator- ( const MatExpr &  e1, const MatExpr &  e2  )

related

template<typename _Tp , int m, int n>

static MatExpr operator- ( const Mat &  a, const Matx< _Tp, m, n > &  b  )

related

template<typename _Tp , int m, int n>

static MatExpr operator- ( const Matx< _Tp, m, n > &  a, const Mat &  b  )

related

MatExpr operator- ( const Mat &  m )

related

MatExpr operator- ( const MatExpr &  e )

related

MatExpr operator/ ( const Mat &  a, const Mat &  b  )

related

MatExpr operator/ ( const Mat &  a, double  s  )

related

MatExpr operator/ ( double  s, const Mat &  a  )

related

MatExpr operator/ ( const MatExpr &  e, const Mat &  m  )

related

MatExpr operator/ ( const Mat &  m, const MatExpr &  e  )

related

MatExpr operator/ ( const MatExpr &  e, double  s  )

related

MatExpr operator/ ( double  s, const MatExpr &  e  )

related

MatExpr operator/ ( const MatExpr &  e1, const MatExpr &  e2  )

related

template<typename _Tp , int m, int n>

static MatExpr operator/ ( const Mat &  a, const Matx< _Tp, m, n > &  b  )

related

template<typename _Tp , int m, int n>

static MatExpr operator/ ( const Matx< _Tp, m, n > &  a, const Mat &  b  )

related

MatExpr operator< ( const Mat &  a, const Mat &  b  )

related

MatExpr operator< ( const Mat &  a, double  s  )

related

MatExpr operator< ( double  s, const Mat &  a  )

related

template<typename _Tp , int m, int n>

static MatExpr operator< ( const Mat &  a, const Matx< _Tp, m, n > &  b  )

related

template<typename _Tp , int m, int n>

static MatExpr operator< ( const Matx< _Tp, m, n > &  a, const Mat &  b  )

related

MatExpr operator<= ( const Mat &  a, const Mat &  b  )

related

MatExpr operator<= ( const Mat &  a, double  s  )

related

MatExpr operator<= ( double  s, const Mat &  a  )

related

template<typename _Tp , int m, int n>

static MatExpr operator<= ( const Mat &  a, const Matx< _Tp, m, n > &  b  )

related

template<typename _Tp , int m, int n>

static MatExpr operator<= ( const Matx< _Tp, m, n > &  a, const Mat &  b  )

related

MatExpr operator== ( const Mat &  a, const Mat &  b  )

related

MatExpr operator== ( const Mat &  a, double  s  )

related

MatExpr operator== ( double  s, const Mat &  a  )

related

template<typename _Tp , int m, int n>

static MatExpr operator== ( const Mat &  a, const Matx< _Tp, m, n > &  b  )

related

template<typename _Tp , int m, int n>

static MatExpr operator== ( const Matx< _Tp, m, n > &  a, const Mat &  b  )

related

MatExpr operator> ( const Mat &  a, const Mat &  b  )

related

MatExpr operator> ( const Mat &  a, double  s  )

related

MatExpr operator> ( double  s, const Mat &  a  )

related

template<typename _Tp , int m, int n>

static MatExpr operator> ( const Mat &  a, const Matx< _Tp, m, n > &  b  )

related

template<typename _Tp , int m, int n>

static MatExpr operator> ( const Matx< _Tp, m, n > &  a, const Mat &  b  )

related

MatExpr operator>= ( const Mat &  a, const Mat &  b  )

related

MatExpr operator>= ( const Mat &  a, double  s  )

related

MatExpr operator>= ( double  s, const Mat &  a  )

related

template<typename _Tp , int m, int n>

static MatExpr operator>= ( const Mat &  a, const Matx< _Tp, m, n > &  b  )

related

template<typename _Tp , int m, int n>

static MatExpr operator>= ( const Matx< _Tp, m, n > &  a, const Mat &  b  )

related

MatExpr operator^ ( const Mat &  a, const Mat &  b  )

related

MatExpr operator^ ( const Mat &  a, const Scalar &  s  )

related

MatExpr operator^ ( const Scalar &  s, const Mat &  a  )

related

template<typename _Tp , int m, int n>

static MatExpr operator^ ( const Mat &  a, const Matx< _Tp, m, n > &  b  )

related

template<typename _Tp , int m, int n>

static MatExpr operator^ ( const Matx< _Tp, m, n > &  a, const Mat &  b  )

related

MatExpr operator| ( const Mat &  a, const Mat &  b  )

related

MatExpr operator| ( const Mat &  a, const Scalar &  s  )

related

MatExpr operator| ( const Scalar &  s, const Mat &  a  )

related

template<typename _Tp , int m, int n>

static MatExpr operator| ( const Mat &  a, const Matx< _Tp, m, n > &  b  )

related

template<typename _Tp , int m, int n>

static MatExpr operator| ( const Matx< _Tp, m, n > &  a, const Mat &  b  )

related

MatExpr operator~ ( const Mat &  m )

related

Member Data Documentation

Mat cv::MatExpr::a

double cv::MatExpr::alpha

Mat cv::MatExpr::b

double cv::MatExpr::beta

Mat cv::MatExpr::c

int cv::MatExpr::flags

const MatOp* cv::MatExpr::op

Scalar cv::MatExpr::s

---

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

• core/include/opencv2/core/mat.hpp