Opencv matrix operations (3), opencv matrix operations

Opencv matrix operations (3), opencv matrix operations
Introduction

This article undertakes the previous article and continues to use matrix computing functions under opencv.

Specific Code for Matrix Replication

    printf("mat1:\n");    showMatdate(mat1);     mat3 = Mat(3, 3, CV_64FC1);    src3 = mat3;     cvRepeat(&src1, &src3);    printf("cvRepeat(mat1):\n");    showMatdate(mat3);

Result Display

Code for adding matrix proportions

    printf("mat1:\n");    showMatdate(mat1);    printf("mat2:\n");    showMatdate(mat2);     mat3 = Mat(3, 3, CV_64FC1);    src3 = mat3;     tmp.val[0] = 1.5;    cvScaleAdd(&src1, tmp, &src2, &src3);    printf("cvScaleAdd(mat1, tmp, mat2):\n");    showMatdate(mat3);

Note: mat3 = mat1 * tmp + mat2;

Result Display

Code for initializing the diagonal element of a Matrix

    printf("mat1:\n");    showMatdate(mat1);     mat3 = Mat(3, 3, CV_64FC1);    src3 = mat3;     tmp.val[0] = 1.5;    cvSetIdentity(&src1, tmp);    printf("cvSetIdentity(mat1, tmp):\n");                                                                                               showMatdate(mat1);

Note: The diagonal element is initially tmp, and the other elements are 0.

Result Display

Cubic Curve Equation solid root code

    printf("mat2:\n");    showMatdate(mat2);     mat3 = Mat(1, 3, CV_64FC1);    src3 = mat3;     CvMat tmp1 = mat2;    CvMat tmp2 = mat3;     cvSolveCubic(&tmp1, &tmp2);    printf("cvSolveCubic(mat2):\n");    showMatdate(mat3);

Note: there can be one or three solid roots.

Result Display

Code for Matrix Subtraction

    printf("mat1:\n");    showMatdate(mat1);    printf("mat2:\n");    showMatdate(mat2);     mat3 = Mat(3, 3, CV_64FC1);    src3 = mat3;     cvSub(&src1, &src2, &src3);    printf("cvSub(mat1, mat2):\n");                                                                                                      showMatdate(mat3);

Note: 1. You can select mask control at the end of void cvSub (const CvArr * src1, const CvArr * src2, CvArr * dst, and const CvArr * mask = NULL. 2. void cvSubRS (const CvArr * src, CvScalar value, CvArr * dst, const CvArr * mask = NULL) dst = value-src. 3. cvSubS (const CvArr * src, CvScalar value, CvArr * dst, const CvArr * mask = NULL) dst = src-val.

Result Display

Code for calculating the sum of Matrix Elements

    printf("mat1:\n");    showMatdate(mat1);     tmp = cvSum(&src1);    printf("cvSum(mat1);%lf\n", tmp.val[0]);

Result Display

Code for the sum of diagonal elements

    printf("mat1:\n");    showMatdate(mat1);     tmp = cvTrace(&src1);    printf("cvTrace(mat1);%lf\n", tmp.val[0]);

Result Display

Code for converting a computing matrix

    printf("mat1:\n");    showMatdate(mat1);     cvTranspose(&src1, &src3);    printf("cvTranspose(mat1);\n");    showMatdate(mat3);

Result Display

Other matrix operations
1. covariance of the calculated vector: calcCovarMatrix
2. Calculate the two-dimensional vector size and angle: cartToPolar
3. Check the invalid value in the input matrix: checkRange
4. convert other matrix formats to Mat: C ++: Mat cvarrToMat (const CvArr * arr, bool copyData = false, bool allowND = true, int coiMode = 0)
5. Perform a one-dimensional or two-dimensional array cosine transformation: C ++: void dct (InputArray src, OutputArray dst, int flags = 0)
6. Execute the forward and inverse Fourier transformation of one-dimensional or two-dimensional arrays: C ++: void dft (InputArray src, OutputArray dst, int flags = 0, int nonzeroRows = 0)
7. Calculate the feature values and feature vectors of the symmetric matrix: void cvEigenVV (CvArr * mat, CvArr * evects, CvArr * evals, double eps = 0, int lowindex =-1, int highindex =-1)
8. Extract the selected image channel: void extractImageCOI (const CvArr * arr, OutputArray coiimg, int coi =-1)
9. Copy an image channel data to the old channel: void insertImageCOI (InputArray coiimg, CvArr * arr, int coi =-1)
10. Perform generalized matrix multiplication: void cvGEMM (const CvArr * src1, const CvArr * src2, double alpha, const CvArr * src3, double beta, CvArr * dst, int tABC = 0)
11. Return the optimal DFT size of the given vector: C ++: int getOptimalDFTSize (int vecsize)
12. Returns a single pixel Conversion Function: C ++: ConvertData getConvertElem (int fromType, int toType)
13. Calculate the inverse Discrete Cosine transformation of one or two dimensions: C ++: void idct (InputArray src, OutputArray dst, int flags = 0)
14. Calculate one-dimensional or inverse Discrete Fourier Transformation: C ++: void idft (InputArray src, OutputArray dst, int flags = 0, int nonzeroRows = 0)
15. Check whether the array element is located between other array elements: C ++: void inRange (InputArray src, InputArray lowerb, InputArray upperb, OutputArray dst)
16. Vector perspective matrix transformation void cvPerspectiveTransform (const CvArr * src, CvArr * dst, const CvMat * mat)
17. Solves the least square method of one or more linear systems. Int cvSolve (const CvArr * src1, const CvArr * src2, CvArr * dst, int method = CV_LU)
18. Perform matrix transformation for each array element (which can be used for image rotation ). Void cvTransform (const CvArr * src, CvArr * dst, const CvMat * transmat, const CvMat * shiftvec = NULL)

Copyright Disclaimer: This article is an original article by the blogger and cannot be reproduced without the permission of the blogger.