radon_d2d

3D Radon transformation

Syntax:

[P] = radon_d2d(M, object_size, radon_pars) [l, P] = radon_d2d(M, object_size, radon_pars)

Description:

M - matrix of an object (float, NxNxN, N - matrix dimension) object_size - matrix size (float, cm) radon_pars - Radon transformation parameters (structure) ~.un - unit vectors of directions (float, Nx2 or Nx3, N-number of projection) ~.size - projection length (float, cm) ~.nBins - projection array length (int) ~.l - projection spatial support (float, cm, Mx1, M - projection length) (size, nBins) and l are mutually exclusive definitions P - projection data (float, MxN, M - projection length, N-number of projection) l - axis of projection (float, cm, Mx1, M - projection length)

Example:

sphere.r=3; % radius of the sphere sphere.offset=[-.5,1,0]; % offset of the sphere sphere.size=10; % size of imaged area sphere.nBins=64; % matrix size phantom = radon_phantom(sphere); % Generate equal solid angle layout of projections fbp_struct.nAz = 12; fbp_struct.nPolar = 12; fbp_struct.imtype = iradon_GetFBPImageType('XYZ'); fbp_struct.MaxGradient = 1; % maximum gradient (G/cm) fbp_struct.angle_sampling = 'UNIFORM_SPATIAL_FLIP'; pars = iradon_FBPGradTable(fbp_struct); % Radon transformation parameters radon_pars.un = pars.G; % unit vectors of the gradients radon_pars.size = 10; % projection spatial support (cm) radon_pars.nBins = 64; % length of the projection spatial support P = radon_d2d(phantom, sphere.size, radon_pars); MatrixGUI(P);

Legend: EPR-IT functions; MATLAB functions; comments.

Reconstruction of the obtained projections

Example:

% convert serial projection layout into iradon_d2d_mstage layout PP = zeros(size(P,1), fbp_struct.nAz*fbp_struct.nPolar); PP(:,pars.gidx) = P; Pela = reshape(PP, [size(P,1), 1, fbp_struct.nAz, fbp_struct.nPolar]); % Interpolate projections to the uniform angular scheme switch fbp_struct.angle_sampling case {'UNIFORM_SPATIAL_FLIP', 'UNIFORM_SPATIAL'} Pela=iradon_InterpToUniformAngle(Pela, 'imgData'); end radon_pars.ELA = fbp_struct; recon_pars.size = 5; % ignored, radon_pars.size is used instead recon_pars.nBins = 128; % ignored, radon_pars.nBins is used instead recon_pars.Filter = 'ram-lak'; recon_pars.FilterCutOff = 1.0; recon_pars.Interpolation = 'spline'; recon_pars.InterpFactor = 2; recon_pars.CodeFlag = 'C'; recon_pars.zeropadding = 2; % any number >= 1 % call the reconstruction program and display result image = iradon_d2d_mstage(Pela, radon_pars, recon_pars); ibGUI(image);

Legend: EPR-IT functions; MATLAB functions; comments.

See also:

radon_angle2xyz, radon_c2d_sphere, radon_c2d_cube