Hough transform old opencv convert into new opencv - c++

Question

i am trying to make hough transformation to parallel programming this is a code that i found online and i am new in using opencv2 in c++ anyone know how to convert this code into new open cv code?
//Next do the Canney and Hough transforms on the smaller image
IplImage* src;
src=cvLoadImage(fileName, 0);
IplImage* dst = cvCreateImage( cvGetSize(src), 8, 1 );
IplImage* color_dst = cvCreateImage( cvGetSize(src), 8, 3 );
IplImage* final_dst = cvCreateImage( cvGetSize(src), 8, 1 );
CvMemStorage* storage = cvCreateMemStorage(0);
CvSeq* lines = 0;
int i;
cvCanny( src, dst, 50, 200, 3 );
cvCvtColor( dst, color_dst, CV_GRAY2BGR );
lines = cvHoughLines2( dst,
storage,
CV_HOUGH_STANDARD,
1,
CV_PI/180,
100,
0,
0 );
for( i = 0; i < MIN(lines->total,100); i++ )
{
float* line = (float*)cvGetSeqElem(lines,i);
float rho = line[0];
float theta = line[1];
CvPoint pt1, pt2;
double a = cos(theta), b = sin(theta);
double x0 = a*rho, y0 = b*rho;
pt1.x = cvRound(x0 + 1000*(-b));
pt1.y = cvRound(y0 + 1000*(a));
pt2.x = cvRound(x0 - 1000*(-b));
pt2.y = cvRound(y0 - 1000*(a));
cvLine( color_dst, pt1, pt2, CV_RGB(255,0,0), 2, 8 );
}
cvCvtColor(color_dst, final_dst, CV_BGR2GRAY);
cvSaveImage(fileName, final_dst);
i have tried a bit but i think i fail
//Next do the Hough transforms on the smaller image
cv::Mat src = cv::imread(fileName);
cv::Mat dst;
cv::Mat color_dst;
cv::Mat final_dst;
//IplImage src;
//src=cvLoadImage(fileName, 0);
//IplImage* dst = cvCreateImage( cvGetSize(src), 8, 1 );
//IplImage* color_dst = cvCreateImage( cvGetSize(src), 8, 3 );
//IplImage* final_dst = cvCreateImage( cvGetSize(src), 8, 1 );
//CvMemStorage* storage = cvCreateMemStorage(0);
cv::namedWindow(CW_IMG_ORIGINAL, cv::WINDOW_NORMAL);
cv::resizeWindow(CW_IMG_ORIGINAL, 1280, 720);
cv::moveWindow(CW_IMG_ORIGINAL, 10, 10);
cv::Mat lines;
//CvSeq* lines = 0;
//cv::Seq<linesTp>;
int i;
cvHoughLines2;
cv::Canny( src, dst, 50, 200, 3 );
cv::cvtColor( dst, color_dst, CV_GRAY2BGR );
cv::HoughLines( dst,lines,
CV_HOUGH_STANDARD,
1,
CV_PI/180,
100,
0,
0 );
for( i = 0; i < 100; i++ )
{
//float* line = (float*)cv::getSeqElem(lines, i);
float* line = lines.at(i);
float rho = line[0];
float theta = line[1];
cv::Point pt1, pt2;
double a = cos(theta), b = sin(theta);
double x0 = a*rho, y0 = b*rho;
pt1.x = cvRound(x0 + 1000*(-b));
pt1.y = cvRound(y0 + 1000*(a));
pt2.x = cvRound(x0 - 1000*(-b));
pt2.y = cvRound(y0 - 1000*(a));
cv::line(color_dst, pt1, pt2, CV_RGB(255, 0, 0), 2, 8);
}
cv::cvtColor(color_dst, final_dst, CV_BGR2GRAY);
cv::imshow(CW_IMG_ORIGINAL,final_dst);
I fail due to i dono how to implement the hough lines into the line to do the iteration of the formula previously using cvhoughlines2 but cvhoughlines2 need to insert as cvArr but the cvLoadImage is not currently working in opencv4.1.2 so that I cant use IplImage and cvLoadImage to run this code.