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मैं स्टीरियो दृष्टि के लिए अपने दो प्वाइंट ग्रे (ब्लैकफ्लाई) कैमरों को कैलिब्रेट करने की कोशिश कर रहा हूं। मैं ट्यूटोरियल stereo_calib.cpp का उपयोग कर रहा हूं जो OpenCV (नीचे कोड) के साथ आता है। किसी कारण से, मुझे वास्तव में खराब परिणाम मिल रहे हैं (आरएमएस त्रुटि = 4.4 9 756 और औसत reprojection त्रुटि = 8.06533) और मेरी सभी संशोधित छवियां ग्रे बाहर आती हैं। मुझे लगता है कि मेरी समस्या यह है कि मैं स्टीरियो कैलिब्रेट() फ़ंक्शन के लिए सही झंडे नहीं चुन रहा हूं, लेकिन मैंने कई अलग-अलग संयोजनों की कोशिश की है और सबसे अच्छी तरह से संशोधित छवियों को तोड़ दिया जाएगा।ओपनसीवी स्टीरियो कैमरा अंशांकन/छवि संशोधन
यहां छवियों मैं प्रयोग किया जाता के लिए एक लिंक और एक नमूना सुधारा जोड़ी है: https://www.dropbox.com/sh/5wp31o8xcn6vmjl/AAADAfGiaT_NyXEB3zMpcEvVa#/
किसी भी मदद की सराहना की जाएगी !!
static void
StereoCalib(const vector<string>& imagelist, Size boardSize, bool useCalibrated=true, bool showRectified=true)
{
if(imagelist.size() % 2 != 0)
{
cout << "Error: the image list contains odd (non-even) number of elements\n";
return;
}
bool displayCorners = true;//false;//true;
const int maxScale = 1;//2;
const float squareSize = 1.8;
//const float squareSize = 1.f; // Set this to your actual square size
// ARRAY AND VECTOR STORAGE:
vector<vector<Point2f> > imagePoints[2];
vector<vector<Point3f> > objectPoints;
Size imageSize;
//int i, j, k, nimages = (int)imagelist.size()/2;
int i, j, k, nimages = (int)imagelist.size();
cout << "nimages: " << nimages << "\n";
imagePoints[0].resize(nimages);
imagePoints[1].resize(nimages);
vector<string> goodImageList;
for(i = j = 0; i < nimages; i++)
{
for(k = 0; k < 2; k++)
{
const string& filename = imagelist[i*2+k];
Mat img = imread(filename, 0);
if(img.empty()) {
break;
}
if(imageSize == Size()) {
imageSize = img.size();
} else if(img.size() != imageSize)
{
cout << "The image " << filename << " has the size different from the first image size. Skipping the pair\n";
break;
}
bool found = false;
vector<Point2f>& corners = imagePoints[k][j];
for(int scale = 1; scale <= maxScale; scale++)
{
Mat timg;
if(scale == 1)
timg = img;
else
resize(img, timg, Size(), scale, scale);
found = findChessboardCorners(timg, boardSize, corners,
CV_CALIB_CB_ADAPTIVE_THRESH | CV_CALIB_CB_NORMALIZE_IMAGE);
if(found)
{
if(scale > 1)
{
Mat cornersMat(corners);
cornersMat *= 1./scale;
}
break;
}
}
if(displayCorners)
{
cout << filename << endl;
Mat cimg, cimg1;
cvtColor(img, cimg, COLOR_GRAY2BGR);
drawChessboardCorners(cimg, boardSize, corners, found);
double sf = 1280./MAX(img.rows, img.cols);
resize(cimg, cimg1, Size(), sf, sf);
imshow("corners", cimg1);
char c = (char)waitKey(500);
if(c == 27 || c == 'q' || c == 'Q') //Allow ESC to quit
exit(-1);
}
else
putchar('.');
if(!found) {
cout << "!found\n";
break;
}
cornerSubPix(img, corners, Size(11,11), Size(-1,-1),
TermCriteria(CV_TERMCRIT_ITER+CV_TERMCRIT_EPS,
30, 0.01));
}
if(k == 2)
{
goodImageList.push_back(imagelist[i*2]);
goodImageList.push_back(imagelist[i*2+1]);
j++;
}
}
cout << j << " pairs have been successfully detected.\n";
nimages = j;
if(nimages < 2)
{
cout << "Error: too little pairs to run the calibration\n";
return;
}
imagePoints[0].resize(nimages);
imagePoints[1].resize(nimages);
objectPoints.resize(nimages);
for(i = 0; i < nimages; i++)
{
for(j = 0; j < boardSize.height; j++)
for(k = 0; k < boardSize.width; k++)
objectPoints[i].push_back(Point3f(j*squareSize, k*squareSize, 0));
}
cout << "Running stereo calibration ...\n";
Mat cameraMatrix[2], distCoeffs[2];
cameraMatrix[0] = Mat::eye(3, 3, CV_64F);
cameraMatrix[1] = Mat::eye(3, 3, CV_64F);
Mat R, T, E, F;
double rms = stereoCalibrate(objectPoints, imagePoints[0], imagePoints[1],
cameraMatrix[0], distCoeffs[0],
cameraMatrix[1], distCoeffs[1],
imageSize, R, T, E, F,
//TermCriteria(CV_TERMCRIT_ITER+CV_TERMCRIT_EPS, 100, 1e-5));
TermCriteria(CV_TERMCRIT_ITER+CV_TERMCRIT_EPS, 100, 1e-5),
CV_CALIB_FIX_ASPECT_RATIO +
//CV_CALIB_ZERO_TANGENT_DIST +
CV_CALIB_SAME_FOCAL_LENGTH +
CV_CALIB_RATIONAL_MODEL +
//CV_CALIB_FIX_K3);
//CV_CALIB_FIX_K2);
CV_CALIB_FIX_K3 + CV_CALIB_FIX_K4 + CV_CALIB_FIX_K5);
//CV_CALIB_FIX_K1 + CV_CALIB_FIX_K2 + CV_CALIB_FIX_K3 + CV_CALIB_FIX_K4 + CV_CALIB_FIX_K5);
cout << "done with RMS error=" << rms << endl;
double err = 0;
int npoints = 0;
vector<Vec3f> lines[2];
for(i = 0; i < nimages; i++)
{
int npt = (int)imagePoints[0][i].size();
Mat imgpt[2];
for(k = 0; k < 2; k++)
{
imgpt[k] = Mat(imagePoints[k][i]);
undistortPoints(imgpt[k], imgpt[k], cameraMatrix[k], distCoeffs[k], Mat(), cameraMatrix[k]);
computeCorrespondEpilines(imgpt[k], k+1, F, lines[k]);
}
for(j = 0; j < npt; j++)
{
double errij = fabs(imagePoints[0][i][j].x*lines[1][j][0] +
imagePoints[0][i][j].y*lines[1][j][1] + lines[1][j][2]) +
fabs(imagePoints[1][i][j].x*lines[0][j][0] +
imagePoints[1][i][j].y*lines[0][j][1] + lines[0][j][2]);
err += errij;
}
npoints += npt;
}
cout << "average reprojection err = " << err/npoints << endl;
// save intrinsic parameters
FileStorage fs("intrinsics.yml", CV_STORAGE_WRITE);
if(fs.isOpened())
{
fs << "M1" << cameraMatrix[0] << "D1" << distCoeffs[0] <<
"M2" << cameraMatrix[1] << "D2" << distCoeffs[1];
fs.release();
}
else
cout << "Error: can not save the intrinsic parameters\n";
Mat R1, R2, P1, P2, Q;
Rect validRoi[2];
stereoRectify(cameraMatrix[0], distCoeffs[0],
cameraMatrix[1], distCoeffs[1],
imageSize, R, T, R1, R2, P1, P2, Q,
//CALIB_ZERO_DISPARITY, 1, imageSize, &validRoi[0], &validRoi[1]);
CALIB_ZERO_DISPARITY, 0, imageSize, &validRoi[0], &validRoi[1]);
fs.open("extrinsics.yml", CV_STORAGE_WRITE);
if(fs.isOpened())
{
fs << "R" << R << "T" << T << "R1" << R1 << "R2" << R2 << "P1" << P1 << "P2" << P2 << "Q" << Q;
fs.release();
}
else
cout << "Error: can not save the intrinsic parameters\n";
// OpenCV can handle left-right
// or up-down camera arrangements
//bool isVerticalStereo = fabs(P2.at<double>(1, 3)) > fabs(P2.at<double>(0, 3));
bool isVerticalStereo = false;
// COMPUTE AND DISPLAY RECTIFICATION
if(!showRectified)
return;
Mat rmap[2][2];
// IF BY CALIBRATED (BOUGUET'S METHOD)
if(useCalibrated)
{
// we already computed everything
}
// OR ELSE HARTLEY'S METHOD
else
// use intrinsic parameters of each camera, but
// compute the rectification transformation directly
// from the fundamental matrix
{
vector<Point2f> allimgpt[2];
for(k = 0; k < 2; k++)
{
for(i = 0; i < nimages; i++)
std::copy(imagePoints[k][i].begin(), imagePoints[k][i].end(), back_inserter(allimgpt[k]));
}
F = findFundamentalMat(Mat(allimgpt[0]), Mat(allimgpt[1]), FM_8POINT, 0, 0);
Mat H1, H2;
stereoRectifyUncalibrated(Mat(allimgpt[0]), Mat(allimgpt[1]), F, imageSize, H1, H2, 3);
R1 = cameraMatrix[0].inv()*H1*cameraMatrix[0];
R2 = cameraMatrix[1].inv()*H2*cameraMatrix[1];
P1 = cameraMatrix[0];
P2 = cameraMatrix[1];
}
//Precompute maps for cv::remap()
initUndistortRectifyMap(cameraMatrix[0], distCoeffs[0], R1, P1, imageSize, CV_16SC2, rmap[0][0], rmap[0][1]);
initUndistortRectifyMap(cameraMatrix[1], distCoeffs[1], R2, P2, imageSize, CV_16SC2, rmap[1][0], rmap[1][1]);
Mat canvas;
double sf;
int w, h;
if(!isVerticalStereo)
{
sf = 600./MAX(imageSize.width, imageSize.height);
w = cvRound(imageSize.width*sf);
h = cvRound(imageSize.height*sf);
canvas.create(h, w*2, CV_8UC3);
}
else
{
sf = 600./MAX(imageSize.width, imageSize.height);
w = cvRound(imageSize.width*sf);
h = cvRound(imageSize.height*sf);
canvas.create(h*2, w, CV_8UC3);
}
for(i = 0; i < nimages; i++)
{
for(k = 0; k < 2; k++)
{
Mat img = imread(goodImageList[i*2+k], 0), rimg, cimg;
remap(img, rimg, rmap[k][0], rmap[k][1], CV_INTER_LINEAR);
cvtColor(rimg, cimg, COLOR_GRAY2BGR);
Mat canvasPart = !isVerticalStereo ? canvas(Rect(w*k, 0, w, h)) : canvas(Rect(0, h*k, w, h));
resize(cimg, canvasPart, canvasPart.size(), 0, 0, CV_INTER_AREA);
if(useCalibrated)
{
Rect vroi(cvRound(validRoi[k].x*sf), cvRound(validRoi[k].y*sf),
cvRound(validRoi[k].width*sf), cvRound(validRoi[k].height*sf));
rectangle(canvasPart, vroi, Scalar(0,0,255), 3, 8);
}
}
if(!isVerticalStereo)
for(j = 0; j < canvas.rows; j += 16)
line(canvas, Point(0, j), Point(canvas.cols, j), Scalar(0, 255, 0), 1, 8);
else
for(j = 0; j < canvas.cols; j += 16)
line(canvas, Point(j, 0), Point(j, canvas.rows), Scalar(0, 255, 0), 1, 8);
imshow("rectified", canvas);
char c = (char)waitKey();
if(c == 27 || c == 'q' || c == 'Q')
break;
}
}