opencv stereo vision depth map, code does not work

Question

I am studying on stereo vision depth map and I am using the opencv library.I wrote a program to obtain depth map. But when program was run I obtained an empty depth map frame.can anybody help me please, what is wrong ? code are shown in below;

#include <opencv/highgui.h>
#include <opencv/cv.h>
#include <stdio.h>
#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>
#include <math.h>
#include <opencv2/calib3d/calib3d.hpp>
#include <opencv2/imgproc/imgproc.hpp>
#include <opencv2/contrib/contrib.hpp>
int main()
{
IplImage* img1 = cvLoadImage("/home/sezen/Masaüstü/imR.png");
IplImage* img2 = cvLoadImage("/home/sezen/Masaüstü/imL.png");

IplImage *rimage = cvCreateImage(
cvSize( img1->width, img1->height ), IPL_DEPTH_8U, 1 );
cvCvtColor( img1, rimage, CV_RGB2GRAY );

IplImage *limage = cvCreateImage(
cvSize( img2->width, img2->height ), IPL_DEPTH_8U, 1 );
cvCvtColor( img2, limage, CV_RGB2GRAY );

cvNamedWindow( "Right", CV_WINDOW_AUTOSIZE );
cvShowImage( "Right", rimage );

cvNamedWindow( "Left", CV_WINDOW_AUTOSIZE );
cvShowImage("Left", limage);

CvMat *matr = cvCreateMat(rimage->height,rimage->width,CV_8UC1 );
CvMat *matl = cvCreateMat(limage->height,limage->width,CV_8UC1 );
CvMat* disp = cvCreateMat(rimage->height,rimage->width,CV_16S);
CvMat* vdisp = cvCreateMat(rimage->height,rimage->width,CV_16S);

cvConvert( rimage, matr );
cvConvert( limage, matl );

CvStereoBMState *BMState = cvCreateStereoBMState();
assert(BMState != 0);
BMState->preFilterSize=21;
BMState->preFilterCap=31;
BMState->SADWindowSize=21;
BMState->minDisparity=0;
BMState->numberOfDisparities=128;
BMState->textureThreshold=10;
BMState->uniquenessRatio=15;


cvFindStereoCorrespondenceBM( matr, matl, disp, BMState);
cvNormalize(disp, vdisp, 0, 255, CV_MINMAX);

cvShowImage("depthmap", vdisp);
cvWaitKey(0);
return 0;
}

Answer 1

Here's a code for disparity map using C++ API. Final image that you normalize should be of type CV_8UC1.

Mat img1, img2, g1, g2;
Mat disp, disp8;

img1 = imread("leftImage.jpg");
img2 = imread("rightImage.jpg");

cvtColor(img1, g1, CV_BGR2GRAY);
cvtColor(img2, g2, CV_BGR2GRAY);

StereoBM sbm;
sbm.state->SADWindowSize = 9;
sbm.state->numberOfDisparities = 112;
sbm.state->preFilterSize = 5;
sbm.state->preFilterCap = 61;
sbm.state->minDisparity = -39;
sbm.state->textureThreshold = 507;
sbm.state->uniquenessRatio = 0;
sbm.state->speckleWindowSize = 0;
sbm.state->speckleRange = 8;
sbm.state->disp12MaxDiff = 1;

sbm(g1, g2, disp);
normalize(disp, disp8, 0, 255, CV_MINMAX, CV_8U);

imshow("left", img1);
imshow("right", img2);
imshow("disp", disp8);