pub struct MatExpr { /* private fields */ }Expand description
Matrix expression representation @anchor MatrixExpressions 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 AT) - 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
- 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_
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);
Implementations§
source§impl MatExpr
impl MatExpr
pub fn default() -> Result<MatExpr>
pub fn from_mat(m: &impl MatTraitConst) -> Result<MatExpr>
sourcepub fn new(
_op: &impl MatOpTraitConst,
_flags: i32,
_a: &impl MatTraitConst,
_b: &impl MatTraitConst,
_c: &impl MatTraitConst,
_alpha: f64,
_beta: f64,
_s: Scalar
) -> Result<MatExpr>
pub fn new( _op: &impl MatOpTraitConst, _flags: i32, _a: &impl MatTraitConst, _b: &impl MatTraitConst, _c: &impl MatTraitConst, _alpha: f64, _beta: f64, _s: Scalar ) -> Result<MatExpr>
§C++ default parameters
- _a: Mat()
- _b: Mat()
- _c: Mat()
- _alpha: 1
- _beta: 1
- _s: Scalar()
Trait Implementations§
source§impl Boxed for MatExpr
impl Boxed for MatExpr
source§unsafe fn from_raw(ptr: <MatExpr as OpenCVFromExtern>::ExternReceive) -> Self
unsafe fn from_raw(ptr: <MatExpr as OpenCVFromExtern>::ExternReceive) -> Self
Wrap the specified raw pointer Read more
source§fn into_raw(self) -> <MatExpr as OpenCVTypeExternContainer>::ExternSendMut
fn into_raw(self) -> <MatExpr as OpenCVTypeExternContainer>::ExternSendMut
Return the underlying raw pointer while consuming this wrapper. Read more
source§fn as_raw(&self) -> <MatExpr as OpenCVTypeExternContainer>::ExternSend
fn as_raw(&self) -> <MatExpr as OpenCVTypeExternContainer>::ExternSend
Return the underlying raw pointer. Read more
source§fn as_raw_mut(
&mut self
) -> <MatExpr as OpenCVTypeExternContainer>::ExternSendMut
fn as_raw_mut( &mut self ) -> <MatExpr as OpenCVTypeExternContainer>::ExternSendMut
Return the underlying mutable raw pointer Read more
source§impl ElemMul<MatExprResult<&Mat>> for &MatExpr
impl ElemMul<MatExprResult<&Mat>> for &MatExpr
type Output = MatExprResult<MatExpr>
fn elem_mul(self, rhs: MatExprResult<&Mat>) -> Self::Output
source§impl ElemMul<MatExprResult<&Mat>> for MatExpr
impl ElemMul<MatExprResult<&Mat>> for MatExpr
type Output = MatExprResult<MatExpr>
fn elem_mul(self, rhs: MatExprResult<&Mat>) -> Self::Output
source§impl ElemMul<MatExprResult<&MatExpr>> for &MatExpr
impl ElemMul<MatExprResult<&MatExpr>> for &MatExpr
type Output = MatExprResult<MatExpr>
fn elem_mul(self, rhs: MatExprResult<&MatExpr>) -> Self::Output
source§impl ElemMul<MatExprResult<&MatExpr>> for MatExpr
impl ElemMul<MatExprResult<&MatExpr>> for MatExpr
type Output = MatExprResult<MatExpr>
fn elem_mul(self, rhs: MatExprResult<&MatExpr>) -> Self::Output
source§impl ElemMul<MatExprResult<Mat>> for &MatExpr
impl ElemMul<MatExprResult<Mat>> for &MatExpr
type Output = MatExprResult<MatExpr>
fn elem_mul(self, rhs: MatExprResult<Mat>) -> Self::Output
source§impl ElemMul<MatExprResult<Mat>> for MatExpr
impl ElemMul<MatExprResult<Mat>> for MatExpr
type Output = MatExprResult<MatExpr>
fn elem_mul(self, rhs: MatExprResult<Mat>) -> Self::Output
source§impl ElemMul<MatExprResult<MatExpr>> for &MatExpr
impl ElemMul<MatExprResult<MatExpr>> for &MatExpr
type Output = MatExprResult<MatExpr>
fn elem_mul(self, rhs: MatExprResult<MatExpr>) -> Self::Output
source§impl ElemMul<MatExprResult<MatExpr>> for MatExpr
impl ElemMul<MatExprResult<MatExpr>> for MatExpr
type Output = MatExprResult<MatExpr>
fn elem_mul(self, rhs: MatExprResult<MatExpr>) -> Self::Output
source§impl MatExprTrait for MatExpr
impl MatExprTrait for MatExpr
fn as_raw_mut_MatExpr(&mut self) -> *mut c_void
fn set_flags(&mut self, val: i32)
fn set_a(&mut self, val: Mat)
fn set_b(&mut self, val: Mat)
fn set_c(&mut self, val: Mat)
fn set_alpha(&mut self, val: f64)
fn set_beta(&mut self, val: f64)
fn set_s(&mut self, val: Scalar)
fn swap(&mut self, b: &mut impl MatExprTrait) -> Result<()>
source§impl MatExprTraitConst for MatExpr
impl MatExprTraitConst for MatExpr
fn as_raw_MatExpr(&self) -> *const c_void
fn flags(&self) -> i32
fn a(&self) -> Mat
fn b(&self) -> Mat
fn c(&self) -> Mat
fn alpha(&self) -> f64
fn beta(&self) -> f64
fn s(&self) -> Scalar
fn to_mat(&self) -> Result<Mat>
fn size(&self) -> Result<Size>
fn typ(&self) -> Result<i32>
fn row(&self, y: i32) -> Result<MatExpr>
fn col(&self, x: i32) -> Result<MatExpr>
fn rowscols( &self, row_range: &impl RangeTraitConst, col_range: &impl RangeTraitConst ) -> Result<MatExpr>
fn roi(&self, roi: Rect) -> Result<MatExpr>
fn t(&self) -> Result<MatExpr>
source§fn mul_matexpr(&self, e: &impl MatExprTraitConst, scale: f64) -> Result<MatExpr>
fn mul_matexpr(&self, e: &impl MatExprTraitConst, scale: f64) -> Result<MatExpr>
C++ default parameters Read more
source§fn mul_matexpr_def(&self, e: &impl MatExprTraitConst) -> Result<MatExpr>
fn mul_matexpr_def(&self, e: &impl MatExprTraitConst) -> Result<MatExpr>
Note Read more
source§fn mul(&self, m: &impl MatTraitConst, scale: f64) -> Result<MatExpr>
fn mul(&self, m: &impl MatTraitConst, scale: f64) -> Result<MatExpr>
C++ default parameters Read more
fn cross(&self, m: &impl MatTraitConst) -> Result<Mat>
fn dot(&self, m: &impl MatTraitConst) -> Result<f64>
source§impl ToInputArray for &MatExpr
impl ToInputArray for &MatExpr
fn input_array(&self) -> Result<BoxedRef<'_, _InputArray>>
source§impl ToInputArray for MatExpr
impl ToInputArray for MatExpr
fn input_array(&self) -> Result<BoxedRef<'_, _InputArray>>
impl Send for MatExpr
Auto Trait Implementations§
impl Freeze for MatExpr
impl RefUnwindSafe for MatExpr
impl !Sync for MatExpr
impl Unpin for MatExpr
impl UnwindSafe for MatExpr
Blanket Implementations§
source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more
source§impl<Mat> ModifyInplace for Matwhere
Mat: Boxed,
impl<Mat> ModifyInplace for Matwhere
Mat: Boxed,
source§unsafe fn modify_inplace<Res>(
&mut self,
f: impl FnOnce(&Mat, &mut Mat) -> Res
) -> Res
unsafe fn modify_inplace<Res>( &mut self, f: impl FnOnce(&Mat, &mut Mat) -> Res ) -> Res
Helper function to call OpenCV functions that allow in-place modification of a
Mat or another similar object. By passing
a mutable reference to the Mat to this function your closure will get called with the read reference and a write references
to the same Mat. This is of course unsafe as it breaks the Rust aliasing rules, but it might be useful for some performance
sensitive operations. One example of an OpenCV function that allows such in-place modification is imgproc::threshold. Read more