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我正在实现立体视觉深度映射，如 O'reilly 书的 opencv 教科书中的示例所示。

在实现此代码时，我的相机都是水平的并且两者都不相同。执行代码后，我得到了非常奇怪的结果。我想验证这些奇怪的结果是只是因为相机迷失方向还是代码中有任何问题，请帮助我。

#include "cv.h"
#include "cxmisc.h"
#include "highgui.h"
//#include "cvaux.h"
#include <vector>
#include <string>
#include <algorithm>
#include <stdio.h>
#include <ctype.h>
#define WIDTH 426
#define HEIGHT 320


using namespace std;
int main()
{
    //---------Initial--------
    int  nx=7, ny=7, frame = 0, n_boards =20, N;
    int count1 = 0,count2 = 0, result1=0, result2=0;
    int showUndistorted = 1, successes1 = 0,successes2 = 0 ;
    const int maxScale = 1;
    const float squareSize = 2.f;        //Set this to your actual square size
    CvSize imageSize = {WIDTH,HEIGHT};
    CvCapture *capture1= NULL, *capture2= NULL;
    CvSize board_sz = cvSize( nx,ny );

    int i, j, n = nx*ny, N1 = 0, N2 = 0;
    vector<CvPoint2D32f> points[2];
    vector<int> npoints;
    vector<CvPoint3D32f> objectPoints;
    vector<CvPoint2D32f> temp1(n);
    vector<CvPoint2D32f> temp2(n);

    double M1[3][3], M2[3][3], D1[5], D2[5];
    double R[3][3], T[3], E[3][3], F[3][3];
    double Q[4][4];
    CvMat _Q = cvMat(4,4, CV_64F, Q);
    CvMat _M1 = cvMat(3, 3, CV_64F, M1 );
    CvMat _M2 = cvMat(3, 3, CV_64F, M2 );
    CvMat _D1 = cvMat(1, 5, CV_64F, D1 );
    CvMat _D2 = cvMat(1, 5, CV_64F, D2 );
    CvMat _R = cvMat(3, 3, CV_64F, R );
    CvMat _T = cvMat(3, 1, CV_64F, T );
    CvMat _E = cvMat(3, 3, CV_64F, E );
    CvMat _F = cvMat(3, 3, CV_64F, F );

    //---------Starting WebCam----------
    capture1= cvCaptureFromCAM(0);
    assert(capture1!=NULL); cvWaitKey(0);
    capture2= cvCaptureFromCAM(1);
    assert(capture2!=NULL);

    //assure capture size is correct...
    int res=cvSetCaptureProperty(capture1,CV_CAP_PROP_FRAME_WIDTH,WIDTH);
    printf("%d",res);
    res=cvSetCaptureProperty(capture1,CV_CAP_PROP_FRAME_HEIGHT,HEIGHT);
    printf("%d",res);
    res=cvSetCaptureProperty(capture2,CV_CAP_PROP_FRAME_WIDTH,WIDTH);
    printf("%d",res);
    res=cvSetCaptureProperty(capture2,CV_CAP_PROP_FRAME_HEIGHT,HEIGHT);
    printf("%d",res); fflush(stdout);


    IplImage *frame1 = cvQueryFrame( capture1 );
    IplImage* gray_fr1 = cvCreateImage( cvGetSize(frame1), 8, 1 );
    IplImage *frame2 = cvQueryFrame( capture2 );
    IplImage* gray_fr2 = cvCreateImage( cvGetSize(frame1), 8, 1 );
    //imageSize = cvGetSize(frame1);

    //Show Window
    cvNamedWindow( "camera2", 1 );
    cvNamedWindow( "camera1", 1 );
    cvNamedWindow("corners camera1",1);
    cvNamedWindow("corners camera2",1);
    while((successes1<n_boards)||(successes2<n_boards))
    {

        //--------Find chessboard corner--------------------------------------------------

        if((frame++ % 20) == 0)
        {
            //----------------CAM1-------------------------------------------------------------------------------------------------------
            result1 = cvFindChessboardCorners( frame1, board_sz,&temp1[0], &count1,CV_CALIB_CB_ADAPTIVE_THRESH|CV_CALIB_CB_FILTER_QUADS);
            cvCvtColor( frame1, gray_fr1, CV_BGR2GRAY );


            //----------------CAM2--------------------------------------------------------------------------------------------------------
            result2 = cvFindChessboardCorners( frame2, board_sz,&temp2[0], &count2,CV_CALIB_CB_ADAPTIVE_THRESH|CV_CALIB_CB_FILTER_QUADS);
            cvCvtColor( frame2, gray_fr2, CV_BGR2GRAY );


            if(count1==n&&count2==n&&result1&&result2)
            {
                cvFindCornerSubPix( gray_fr1, &temp1[0], count1,cvSize(11, 11), cvSize(-1,-1),cvTermCriteria(CV_TERMCRIT_ITER+CV_TERMCRIT_EPS,30, 0.01) );
                cvDrawChessboardCorners( frame1, board_sz, &temp1[0], count1, result1 );
                cvShowImage( "corners camera1", frame1 );
                N1 = points[0].size();
                points[0].resize(N1 + n, cvPoint2D32f(0,0));
                copy( temp1.begin(), temp1.end(), points[0].begin() + N1 );
                ++successes1;

                cvFindCornerSubPix( gray_fr2, &temp2[0], count2,cvSize(11, 11), cvSize(-1,-1),cvTermCriteria(CV_TERMCRIT_ITER+CV_TERMCRIT_EPS,30, 0.01) );
                cvDrawChessboardCorners( frame2, board_sz, &temp2[0], count2, result2 );
                cvShowImage( "corners camera2", frame2 );
                N2 = points[1].size();
                points[1].resize(N2 + n, cvPoint2D32f(0,0));
                copy( temp2.begin(), temp2.end(), points[1].begin() + N2 );
                ++successes2;

                putchar('$');
            }

            else
            {        cvShowImage( "corners camera2", gray_fr2 );
                cvShowImage( "corners camera1", gray_fr1 );
            }

            frame1 = cvQueryFrame( capture1 );
            cvShowImage("camera1", frame1);
            frame2 = cvQueryFrame( capture2 );
            cvShowImage("camera2", frame2);

            if(cvWaitKey(15)==27) break;
        }
    }
    cvReleaseCapture( &capture1 );
    cvReleaseCapture( &capture2 );
    cvDestroyWindow("camera1");
    cvDestroyWindow("camera2");
    cvDestroyWindow("corners camera1");
    cvDestroyWindow("corners camera2");
    printf("\n");


    //--------------Calibaration-------------------
    N = n_boards*n;
    objectPoints.resize(N);
    for( i = 0; i < ny; i++ )
    for(j = 0; j < nx; j++ )   objectPoints[i*nx + j] = cvPoint3D32f(i*squareSize, j*squareSize, 0);
    for( i = 1; i < n_boards; i++ ) copy( objectPoints.begin(), objectPoints.begin() + n, objectPoints.begin() + i*n );
    npoints.resize(n_boards,n);

    CvMat _objectPoints = cvMat(1, N, CV_32FC3, &objectPoints[0] );
    CvMat _imagePoints1 = cvMat(1, N, CV_32FC2, &points[0][0] );
    CvMat _imagePoints2 = cvMat(1, N, CV_32FC2, &points[1][0] );
    CvMat _npoints = cvMat(1, npoints.size(), CV_32S, &npoints[0] );
    cvSetIdentity(&_M1);
    cvSetIdentity(&_M2);
    cvZero(&_D1);
    cvZero(&_D2);

    printf("Running stereo calibration ...");
    fflush(stdout);
    cvStereoCalibrate( &_objectPoints, &_imagePoints1, &_imagePoints2, &_npoints,&_M1, &_D1, &_M2, &_D2,imageSize, &_R, &_T, &_E, &_F,
    cvTermCriteria(CV_TERMCRIT_ITER+CV_TERMCRIT_EPS, 100, 1e-5),
    CV_CALIB_FIX_ASPECT_RATIO+CV_CALIB_ZERO_TANGENT_DIST + CV_CALIB_SAME_FOCAL_LENGTH );
    printf("done\n");
    //-------------Undistort------------------------------------------
    cvUndistortPoints( &_imagePoints1, &_imagePoints1,&_M1, &_D1, 0, &_M1 );
    cvUndistortPoints( &_imagePoints2, &_imagePoints2,&_M2, &_D2, 0, &_M2 );

    //--------Using bouguet algorithm-------------------
    CvMat* mx1 = cvCreateMat( imageSize.height,imageSize.width, CV_32F );
    CvMat* my1 = cvCreateMat( imageSize.height,imageSize.width, CV_32F );
    CvMat* mx2 = cvCreateMat( imageSize.height,imageSize.width, CV_32F );
    CvMat* my2 = cvCreateMat( imageSize.height,imageSize.width, CV_32F );
    CvMat* frame1r = cvCreateMat( imageSize.height,imageSize.width, CV_8U );
    CvMat* frame2r = cvCreateMat( imageSize.height,imageSize.width, CV_8U );
    CvMat* disp = cvCreateMat( imageSize.height, imageSize.width, CV_16S );
    CvMat* vdisp = cvCreateMat( imageSize.height,imageSize.width, CV_8U );
    CvMat* Image3D = cvCreateMat(imageSize.height, imageSize.width, CV_32FC3);
    CvMat* pair;
    double R1[3][3], R2[3][3], P1[3][4], P2[3][4];
    CvMat _R1 = cvMat(3, 3, CV_64F, R1);
    CvMat _R2 = cvMat(3, 3, CV_64F, R2);
    //Calib with Bouguet algrithm
    CvMat _P1 = cvMat(3, 4, CV_64F, P1);
    CvMat _P2 = cvMat(3, 4, CV_64F, P2);
    cvStereoRectify( &_M1, &_M2, &_D1, &_D2, imageSize,&_R, &_T,&_R1, &_R2, &_P1, &_P2, &_Q,0/*CV_CALIB_ZERO_DISPARITY*/ );
    //Find matrix for cvRemap()
    cvInitUndistortRectifyMap(&_M1,&_D1,&_R1,&_P1,mx1,my1);
    cvInitUndistortRectifyMap(&_M2,&_D2,&_R2,&_P2,mx2,my2);


    pair = cvCreateMat( imageSize.height, imageSize.width*2,CV_8UC3 );
    //Paramater for stereo corrrespondences
    CvStereoBMState *BMState = cvCreateStereoBMState();
    assert(BMState != 0);
    BMState->preFilterSize=31;
    BMState->preFilterCap=31;
    BMState->SADWindowSize=35;
    BMState->minDisparity= 0;
    BMState->numberOfDisparities=48;
    BMState->textureThreshold=20;        //reduce noise
    BMState->uniquenessRatio=15;        // uniquenessRatio > (match_val–min_match)/min_match.
    /*    CvStereoBMState *state = cvCreateStereoBMState(CV_STEREO_BM_BASIC);
    BMState->speckleRange = 50;
    BMState->textureThreshold = 400;*/

    //Bat camera va hien thi
    //cvNamedWindow( "camera2", 1 );
    //cvNamedWindow( "camera1", 1 );
    cvNamedWindow( "rectified",1 );
    cvNamedWindow( "disparity",1);
    cvNamedWindow("depthmap",1);

    capture1= cvCaptureFromCAM(0);
    assert(capture1!=NULL); cvWaitKey(10);
    capture2= cvCaptureFromCAM(1);
    assert(capture2!=NULL);
    res=cvSetCaptureProperty(capture1,CV_CAP_PROP_FRAME_WIDTH,WIDTH);
    printf("%d",res);
    res=cvSetCaptureProperty(capture1,CV_CAP_PROP_FRAME_HEIGHT,HEIGHT);
    printf("%d",res);
    res=cvSetCaptureProperty(capture2,CV_CAP_PROP_FRAME_WIDTH,WIDTH);
    printf("%d",res);
    res=cvSetCaptureProperty(capture2,CV_CAP_PROP_FRAME_HEIGHT,HEIGHT);
    printf("%d",res); fflush(stdout);

    frame1 = cvQueryFrame( capture1 );
    frame2 = cvQueryFrame( capture2 );


    while(1)
    {
        CvMat part;
        cvCvtColor( frame1, gray_fr1, CV_BGR2GRAY );
        cvCvtColor( frame2, gray_fr2, CV_BGR2GRAY );
        cvRemap( gray_fr1, frame1r, mx1, my1 );
        cvRemap( gray_fr2, frame2r, mx2, my2 );
        cvFindStereoCorrespondenceBM( frame1r, frame2r, disp, BMState);

        /*        cvShowImage("camera1", frame1);
        cvShowImage("camera2", frame2);            */
        //        cvConvertScale( disp, disp, 16, 0 );
        cvNormalize( disp, vdisp, 0, 256, CV_MINMAX );
        cvShowImage( "disparity", vdisp );
        cvReprojectImageTo3D(disp, Image3D, &_Q);
        cvShowImage("depthmap",Image3D);




        //Hien thi anh da rectify
        cvGetCols( pair, &part, 0, imageSize.width );
        cvCvtColor( frame1r, &part, CV_GRAY2BGR );
        cvGetCols( pair, &part, imageSize.width, imageSize.width*2 );
        cvCvtColor( frame2r, &part, CV_GRAY2BGR ); //CV_GRAY2BGR
        for( j = 0; j < imageSize.height; j += 16 )
        cvLine( pair, cvPoint(0,j), cvPoint(imageSize.width*2,j), CV_RGB(0,255,0));
        cvShowImage( "rectified", pair );
        frame1 = cvQueryFrame( capture1 );
        frame2 = cvQueryFrame( capture2 );
        if( cvWaitKey(15) == 27 )  break;
    }
    while( 1 ) { if((cvWaitKey(10)&0x7f) == 27 ) break; }
    cvReleaseStereoBMState(&BMState);
    cvReleaseMat( &mx1 );
    cvReleaseMat( &my1 );
    cvReleaseMat( &mx2 );
    cvReleaseMat( &my2 );
    cvReleaseCapture( &capture1 );
    cvReleaseCapture( &capture2 );
    cvReleaseMat( &frame1r );
    cvReleaseMat( &frame2r );
    cvReleaseMat( &disp );
    cvReleaseMat(&Image3D);

}

这个链接中给出了视差图的照片 一个是网络摄像头另一个是USB摄像头

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1 回答 1

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拥有不同的相机将使您的生活更加困难。首先，我怀疑相机的焦距是否相同，因此CV_CALIB_SAME_FOCAL_LENGTH设置的参数会导致您对这对相机进行错误校准（将其作为固定参数删除，因为它几乎肯定会有所不同）。

此外，在相关参数说明中，您通过径向失真参数 k1 - k6 为校准算法提供了很大的灵活性，因为这些参数都不是固定的。首先尝试使用最少数量的参数来获得良好的拟合。例如，修复除 k1 和 k2 之外的所有内容（即使用CV_CALIB_FIX_K3 + CV_CALIB_FIX_K4 + CV_CALIB_FIX_K5 + CV_CALIB_FIX_K6）。如果这不起作用，请允许 k3 可变等...

编辑： 另一个提示，考虑分别校准每个相机，然后传递CV_CALIB_FIX_INTRINSIC两个相机内在矩阵以缩小搜索空间，这将有望使算法收敛到全局而不是局部校准最小值。

希望有帮助！

于 2012-05-22T15:57:27.023 回答