From b2fc6c70434674d74551c3a6c01ffb3233499312 Mon Sep 17 00:00:00 2001 From: Willem Jan Palenstijn Date: Mon, 1 Jul 2013 22:34:11 +0000 Subject: Update version to 1.3 --- samples/s012_masks.m | 60 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 60 insertions(+) create mode 100644 samples/s012_masks.m (limited to 'samples/s012_masks.m') diff --git a/samples/s012_masks.m b/samples/s012_masks.m new file mode 100644 index 0000000..b7b8df6 --- /dev/null +++ b/samples/s012_masks.m @@ -0,0 +1,60 @@ +%------------------------------------------------------------------------ +% This file is part of the +% All Scale Tomographic Reconstruction Antwerp Toolbox ("ASTRA-Toolbox") +% +% Copyright: iMinds-Vision Lab, University of Antwerp +% License: Open Source under GPLv3 +% Contact: mailto:astra@ua.ac.be +% Website: http://astra.ua.ac.be +%------------------------------------------------------------------------ + + +% In this example we will create a reconstruction in a circular region, +% instead of the usual rectangle. + +% This is done by placing a circular mask on the square reconstruction volume: + +c = -127.5:127.5; +[x y] = meshgrid(-127.5:127.5,-127.5:127.5); +mask = (x.^2 + y.^2 < 127.5^2); + +figure(1); imshow(mask, []); + + +vol_geom = astra_create_vol_geom(256, 256); +proj_geom = astra_create_proj_geom('parallel', 1.0, 384, linspace2(0,pi,50)); + +% As before, create a sinogram from a phantom +P = phantom(256); +[sinogram_id, sinogram] = astra_create_sino_gpu(P, proj_geom, vol_geom); +figure(2); imshow(P, []); +figure(3); imshow(sinogram, []); + +% Create a data object for the reconstruction +rec_id = astra_mex_data2d('create', '-vol', vol_geom); + +% Create a data object for the mask +mask_id = astra_mex_data2d('create', '-vol', vol_geom, mask); + +% Set up the parameters for a reconstruction algorithm using the GPU +cfg = astra_struct('SIRT_CUDA'); +cfg.ReconstructionDataId = rec_id; +cfg.ProjectionDataId = sinogram_id; +cfg.option.ReconstructionMaskId = mask_id; + +% Create the algorithm object from the configuration structure +alg_id = astra_mex_algorithm('create', cfg); + +% Run 150 iterations of the algorithm +astra_mex_algorithm('iterate', alg_id, 150); + +% Get the result +rec = astra_mex_data2d('get', rec_id); +figure(4); imshow(rec, []); + +% Clean up. Note that GPU memory is tied up in the algorithm object, +% and main RAM in the data objects. +astra_mex_algorithm('delete', alg_id); +astra_mex_data2d('delete', mask_id); +astra_mex_data2d('delete', rec_id); +astra_mex_data2d('delete', sinogram_id); -- cgit v1.2.3