VAIRMAP

vairmap − maps image file containing airway to cylindrical model polygon file point

vairmap [if=<image file in short format>] [sf=<cylindrical model polygon file>] [of=<mapped polygon file>] [x=<polynomial coefficients for ’x(t)’>] [y=<polynomial coefficients for ’y(t)’>] [z=<polynomial coefficients for ’z(t)’>] [si=<sampling interval (mm)>] [sd=<sampling distance (mm)>] [tf=<temporary (debugging) vector file>]

vairmap maps image intensity information onto cylindrical model polygon file.

Intensity information is sampled around the parametric polynomial in 3D space (fitted using vfitpoly). Parameters x, y, z are used to specify the coefficients of polynomials, which are the output of vfitpoly. If, the equation of the curve is defined as: x(t) = 50*t^3 + 50*t - 25; y(t) = 50*t^2 - 25; z(t) = 60*t^2 + 60*t - 60, parameters should be set up as: x=50,0,50,-25 y=0,50,0,-25 z=0,60,60,-60. The part of the curve used for sampling is bounded in the interval of parameter t = (0...1).

In the model space, for each triangle of the cylindrical model polygon file, parameter ’t’ is equal to ’z’ coordinate of the polygon’s center point. Direction of the polygon is computed as the angle between direction of ’x’ axis and the vector connecting the axis and the center of the polygon.

For each value of ’t’, corresponding cross-sectional plane is sampled. This plane is perpendicular to the tangent vector of the curve and intersects it at the tangent point x(t), y(t), z(t). Then rays lying on this plane are casted from the tangent point in the precomputed directions of polygons.

The values of image intensity are sampled in the interval ’si’ and recorded to the floating point vector format. Last sampling point is located at distance sampled values is anchored to the corresponding polygon of the model.

Only cubic polynomials are supported

vvec2(1), vadjtopol(1), vadjtover(1), vpoltoadj(1) vpoltover(1), vvertoadj(1), vvertopol(1), vpoldiv(1), vpolcolor(1), vpoltosphere(1), vspheretoplane(1), vspheretoplane(1). vpolmap(1), vcylmodel(1)

J. Lee