/// <summary>
/// computes various useful camera (sensor/lens) characteristics using the computed camera calibration matrix, image frame resolution in pixels and the physical aperture size
/// </summary>
/// <param name="imgWidth">Image width in pixels</param>
/// <param name="imgHeight">Image height in pixels</param>
/// <param name="apertureWidth">Aperture width in realworld units (optional input parameter). Set it to 0 if not used</param>
/// <param name="apertureHeight">Aperture width in realworld units (optional input parameter). Set it to 0 if not used</param>
/// <param name="fovx">Field of view angle in x direction in degrees</param>
/// <param name="fovy">Field of view angle in y direction in degrees </param>
/// <param name="focalLength">Focal length in realworld units </param>
/// <param name="principalPoint">The principal point in realworld units </param>
/// <param name="pixelAspectRatio">The pixel aspect ratio ~ fy/f</param>
public void GetIntrinsicMatrixValues(
int imgWidth,
int imgHeight,
double apertureWidth,
double apertureHeight,
out double fovx,
out double fovy,
out double focalLength,
out MCvPoint2D64f principalPoint,
out double pixelAspectRatio)
{
fovx = 0;
fovy = 0;
focalLength = 0;
principalPoint = new MCvPoint2D64f();
pixelAspectRatio = 0;
CvInvoke.CalibrationMatrixValues(_intrinsicMatrix, new Size(imgWidth, imgHeight), apertureWidth, apertureHeight, ref fovx, ref fovy, ref focalLength, ref principalPoint, ref pixelAspectRatio);
}