public ProjectorCalibrationResult ToProjectorCalibration(CameraCalibrationResult cameraCalibration)
{
//TODO
return(null);
}
// Original method http://docs.opencv.org/2.4/modules/calib3d/doc/camera_calibration_and_3d_reconstruction.html
//// An example of the code working can be found in VVVV
//// vvvv git https://github.com/elliotwoods/VVVV.Nodes.EmguCV/blob/master/src/CameraCalibration/CalibrateCamera.cs
//// to see it working in vvvv, check "{vvvv}\packs\{vvvv.imagepack}\nodes\modules\Image\OpenCV\CalibrateProjector (CV.Transform).v4p"
//// The general idea is to take the camera calibration and use it for a projector, by adding near/far planes
//// The code might be outdated, since they changed the EmguCV interface
// Returns CalibrationCameraResult with the calibration parameters if callibration was possible, null otherwise
public static CameraCalibrationResult ComputeCameraCalibration(
Vector3[] inObjectPoints, // N Points in space(x,y,z)
// * when computing intrinsics, use the checkerboard as reference frame (that means the corners won't move)
// * when computing extrinsics, you can use the checkerboard corners in world coordinates for global position estimation
Vector2[] inImagePoints, // N*S points on the image plane(u,v) matching the N points in space, where
// * for intrinsic computation, S = number of samples
// * for extrinsic computation, S = 1
Size sensorSize, // Size of the image, used only to initialize intrinsic camera matrix
Matrix <double> IntrinsicMatrix, // The output camera matrix(A)[fx 0 cx; 0 fy cy; 0 0 1]. If CV_CALIB_USE_INTRINSIC_GUESS and / or CV_CALIB_FIX_ASPECT_RATION are specified, some or all of fx, fy, cx, cy must be initialized
out string status, // OK if everything went well, verbse error description otherwise
bool intrinsicGuess = true, // If intrinsicGuess is true, the intrinsic matrix will be initialized with default values
bool normalizedImageCoordinates = true, // if true, the image coordinates are normalized between 0-1
CalibType flags = CalibType.UseIntrinsicGuess) // Different flags:
// * If Emgu.CV.CvEnum.CalibType == CV_CALIB_USE_INTRINSIC_GUESS and/or CV_CALIB_FIX_ASPECT_RATIO are specified, some or all of fx, fy, cx, cy must be initialized before calling the function
// * if you use FIX_ASPECT_RATIO and FIX_FOCAL_LEGNTH options, these values needs to be set in the intrinsic parameters before the CalibrateCamera function is called. Otherwise 0 values are used as default.
// flags |= CalibType.UseIntrinsicGuess; // uses the intrinsicMatrix as initial estimation, or generates an initial estimation using imageSize
// flags |= CalibType.FixFocalLength; // if (CV_CALIB_USE_INTRINSIC_GUESS) then: {fx,fy} are constant
// flags |= CalibType.FixAspectRatio; // if (CV_CALIB_USE_INTRINSIC_GUESS) then: fy is a free variable, fx/fy stays constant
// flags |= CalibType.FixPrincipalPoint; // if (CV_CALIB_USE_INTRINSIC_GUESS) then: {cx,cy} are constant
// flags |= (CalibType.FixK1 // Given CalibType.FixK{i}: if (CV_CALIB_USE_INTRINSIC_GUESS) then: K{i} = distortionCoefficents[i], else:k ki = 0
// | CalibType.FixK2
// | CalibType.FixK3
// | CalibType.FixK4
// | CalibType.FixK5
// | CalibType.FixK6);
// flags |= CalibType.ZeroTangentDist; // tangential distortion is zero: {P1,P2} = {0,0}
// flags |= CalibType.RationalModel; // enable K4,k5,k6, disabled by default
{
int nPointsPerImage = inObjectPoints.Length;
if (nPointsPerImage == 0)
{
status = "Insufficient points";
return(null);
}
int nImages = inImagePoints.Length / nPointsPerImage;
Debug.Log("point/images" + nPointsPerImage + "/" + nImages);
//Intrinsics: an inout intrisic matrix, and depending on the calibrationType, the distortion Coefficients
if (intrinsicGuess)
{
IntrinsicMatrix = new Matrix <double>(3, 3);
// NOTE: A possible cause of failure is that this matrix might be transposed (given how openCV handles indexes)
IntrinsicMatrix[0, 0] = sensorSize.Width;
IntrinsicMatrix[1, 1] = sensorSize.Height;
IntrinsicMatrix[0, 2] = sensorSize.Width / 2.0d;
IntrinsicMatrix[1, 2] = sensorSize.Height / 2.0d;
IntrinsicMatrix[2, 2] = 1;
}
Emgu.CV.IInputOutputArray distortionCoeffs = new Matrix <double>(1, 8); // The output 4x1 or 1x4 vector of distortion coefficients[k1, k2, p1, p2]
// Matching world points (3D) to image points (2D), with the accompaining size of the image in pixels
MCvPoint3D32f[][] objectPoints = new MCvPoint3D32f[nImages][]; //The joint matrix of object points, 3xN or Nx3, where N is the total number of points in all views
PointF[][] imagePoints = new PointF[nImages][]; //The joint matrix of corresponding image points, 2xN or Nx2, where N is the total number of points in all views
for (int i = 0; i < nImages; i++)
{
objectPoints[i] = new MCvPoint3D32f[nPointsPerImage];
imagePoints[i] = new PointF[nPointsPerImage];
for (int j = 0; j < nPointsPerImage; j++)
{
objectPoints[i][j].X = inObjectPoints[j].x;
objectPoints[i][j].Y = inObjectPoints[j].y;
objectPoints[i][j].Z = inObjectPoints[j].z;
if (normalizedImageCoordinates)
{
imagePoints[i][j].X = inImagePoints[i * nPointsPerImage + j].x * (sensorSize.Width - 1);
imagePoints[i][j].Y = (1 - inImagePoints[i * nPointsPerImage + j].y) * (sensorSize.Height - 1);
}
else
{
imagePoints[i][j].X = inImagePoints[i * nPointsPerImage + j].x;
imagePoints[i][j].Y = (1 - inImagePoints[i * nPointsPerImage + j].y);
}
}
}
//Extrinsics: they are decomposed in position and orientation
Mat[] rotationVectors; //The output 3xM or Mx3 array of rotation vectors(compact representation of rotation matrices, see cvRodrigues2).
Mat[] translationVectors; //The output 3xM or Mx3 array of translation vectors
// When to end: 10 iterations
Emgu.CV.Structure.MCvTermCriteria termCriteria = new Emgu.CV.Structure.MCvTermCriteria(10); //The termination criteria
try
{
// To make this method work it was necessary to patch it (see below)
double reprojectionError = CalibrateCamera(
objectPoints,
imagePoints,
sensorSize,
IntrinsicMatrix,
distortionCoeffs,
flags,
termCriteria,
out rotationVectors,
out translationVectors);
var rotation = new Matrix <double>(rotationVectors[0].Rows, rotationVectors[0].Cols, rotationVectors[0].DataPointer);
CameraCalibrationResult calibration = new CameraCalibrationResult(
sensorSize.Width, sensorSize.Height,
new CameraCalibrationResult.Extrinsics(MatToVector3(translationVectors[0]), MatToVector3(rotationVectors[0])),
new CameraCalibrationResult.Intrinsics(IntrinsicMatrix, sensorSize),
new CameraCalibrationResult.Distortion(distortionCoeffs),
reprojectionError
);
DebugMatrix(IntrinsicMatrix);
status = "OK! " + reprojectionError;
return(calibration);
}
catch (Exception e)
{ // Error
status = e.Message;
return(null);
}
}
