16 files changed, 864 insertions, 0 deletions
diff --git a/samples/matlab/s001_sinogram_par2d.m b/samples/matlab/s001_sinogram_par2d.m
new file mode 100644
index 0000000..4494e7b
--- /dev/null
+++ b/samples/matlab/s001_sinogram_par2d.m
@@ -0,0 +1,33 @@
+% -----------------------------------------------------------------------
+% This file is part of the ASTRA Toolbox
+% 
+% Copyright: 2010-2015, iMinds-Vision Lab, University of Antwerp
+%            2014-2015, CWI, Amsterdam
+% License: Open Source under GPLv3
+% Contact: astra@uantwerpen.be
+% Website: http://sf.net/projects/astra-toolbox
+% -----------------------------------------------------------------------
+
+% Create a basic 256x256 square volume geometry
+vol_geom = astra_create_vol_geom(256, 256);
+
+% Create a parallel beam geometry with 180 angles between 0 and pi, and
+% 384 detector pixels of width 1.
+% For more details on available geometries, see the online help of the
+% function astra_create_proj_geom .
+proj_geom = astra_create_proj_geom('parallel', 1.0, 384, linspace2(0,pi,180));
+
+% Create a 256x256 phantom image using matlab's built-in phantom() function
+P = phantom(256);
+
+% Create a sinogram using the GPU.
+% Note that the first time the GPU is accessed, there may be a delay
+% of up to 10 seconds for initialization.
+[sinogram_id, sinogram] = astra_create_sino_gpu(P, proj_geom, vol_geom);
+
+figure(1); imshow(P, []);
+figure(2); imshow(sinogram, []);
+
+
+% Free memory
+astra_mex_data2d('delete', sinogram_id);
diff --git a/samples/matlab/s002_data2d.m b/samples/matlab/s002_data2d.m
new file mode 100644
index 0000000..a91071f
--- /dev/null
+++ b/samples/matlab/s002_data2d.m
@@ -0,0 +1,60 @@
+% -----------------------------------------------------------------------
+% This file is part of the ASTRA Toolbox
+% 
+% Copyright: 2010-2015, iMinds-Vision Lab, University of Antwerp
+%            2014-2015, CWI, Amsterdam
+% License: Open Source under GPLv3
+% Contact: astra@uantwerpen.be
+% Website: http://sf.net/projects/astra-toolbox
+% -----------------------------------------------------------------------
+
+vol_geom = astra_create_vol_geom(256, 256);
+
+proj_geom = astra_create_proj_geom('parallel', 1.0, 384, linspace2(0,pi,180));
+
+
+% Create volumes
+
+% initialized to zero
+v0 = astra_mex_data2d('create', '-vol', vol_geom);
+
+% initialized to 3.0
+v1 = astra_mex_data2d('create', '-vol', vol_geom, 3.0);
+
+% initialized to a matrix. A may be a single, double or logical (0/1) array.
+A = phantom(256);
+v2 = astra_mex_data2d('create', '-vol', vol_geom, A);
+
+
+% Projection data
+s0 = astra_mex_data2d('create', '-sino', proj_geom);
+% Initialization to a scalar or a matrix also works, exactly as with a volume.
+
+
+% Update data
+
+% set to zero
+astra_mex_data2d('store', v0, 0);
+
+% set to a matrix
+astra_mex_data2d('store', v2, A);
+
+
+
+% Retrieve data
+
+R = astra_mex_data2d('get', v2);
+imshow(R, []);
+
+
+% Retrieve data as a single array. Since astra internally stores
+% data as single precision, this is more efficient:
+
+R = astra_mex_data2d('get_single', v2);
+
+
+% Free memory
+astra_mex_data2d('delete', v0);
+astra_mex_data2d('delete', v1);
+astra_mex_data2d('delete', v2);
+astra_mex_data2d('delete', s0);
diff --git a/samples/matlab/s003_gpu_reconstruction.m b/samples/matlab/s003_gpu_reconstruction.m
new file mode 100644
index 0000000..efb5c68
--- /dev/null
+++ b/samples/matlab/s003_gpu_reconstruction.m
@@ -0,0 +1,52 @@
+% -----------------------------------------------------------------------
+% This file is part of the ASTRA Toolbox
+% 
+% Copyright: 2010-2015, iMinds-Vision Lab, University of Antwerp
+%            2014-2015, CWI, Amsterdam
+% License: Open Source under GPLv3
+% Contact: astra@uantwerpen.be
+% Website: http://sf.net/projects/astra-toolbox
+% -----------------------------------------------------------------------
+
+vol_geom = astra_create_vol_geom(256, 256);
+proj_geom = astra_create_proj_geom('parallel', 1.0, 384, linspace2(0,pi,180));
+
+% As before, create a sinogram from a phantom
+P = phantom(256);
+[sinogram_id, sinogram] = astra_create_sino_gpu(P, proj_geom, vol_geom);
+figure(1); imshow(P, []);
+figure(2); imshow(sinogram, []);
+
+astra_mex_data2d('delete', sinogram_id);
+
+% We now re-create the sinogram data object as we would do when loading
+% an external sinogram
+sinogram_id = astra_mex_data2d('create', '-sino', proj_geom, sinogram);
+
+% Create a data object for the reconstruction
+rec_id = astra_mex_data2d('create', '-vol', vol_geom);
+
+% Set up the parameters for a reconstruction algorithm using the GPU
+cfg = astra_struct('SIRT_CUDA');
+cfg.ReconstructionDataId = rec_id;
+cfg.ProjectionDataId = sinogram_id;
+
+% Available algorithms:
+% SIRT_CUDA, SART_CUDA, EM_CUDA, FBP_CUDA (see the FBP sample)
+
+
+% 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(3); 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', rec_id);
+astra_mex_data2d('delete', sinogram_id);
diff --git a/samples/matlab/s004_cpu_reconstruction.m b/samples/matlab/s004_cpu_reconstruction.m
new file mode 100644
index 0000000..f25cd2b
--- /dev/null
+++ b/samples/matlab/s004_cpu_reconstruction.m
@@ -0,0 +1,60 @@
+% -----------------------------------------------------------------------
+% This file is part of the ASTRA Toolbox
+% 
+% Copyright: 2010-2015, iMinds-Vision Lab, University of Antwerp
+%            2014-2015, CWI, Amsterdam
+% License: Open Source under GPLv3
+% Contact: astra@uantwerpen.be
+% Website: http://sf.net/projects/astra-toolbox
+% -----------------------------------------------------------------------
+
+vol_geom = astra_create_vol_geom(256, 256);
+proj_geom = astra_create_proj_geom('parallel', 1.0, 384, linspace2(0,pi,180));
+
+% For CPU-based algorithms, a "projector" object specifies the projection
+% model used. In this case, we use the "strip" model.
+proj_id = astra_create_projector('strip', proj_geom, vol_geom);
+
+% Create a sinogram from a phantom
+P = phantom(256);
+[sinogram_id, sinogram] = astra_create_sino(P, proj_id);
+figure(1); imshow(P, []);
+figure(2); imshow(sinogram, []);
+
+astra_mex_data2d('delete', sinogram_id);
+
+% We now re-create the sinogram data object as we would do when loading
+% an external sinogram
+sinogram_id = astra_mex_data2d('create', '-sino', proj_geom, sinogram);
+
+% Create a data object for the reconstruction
+rec_id = astra_mex_data2d('create', '-vol', vol_geom);
+
+% Set up the parameters for a reconstruction algorithm using the CPU
+% The main difference with the configuration of a GPU algorithm is the
+% extra ProjectorId setting.
+cfg = astra_struct('SIRT');
+cfg.ReconstructionDataId = rec_id;
+cfg.ProjectionDataId = sinogram_id;
+cfg.ProjectorId = proj_id;
+
+% Available algorithms:
+% ART, SART, SIRT, CGLS, FBP
+
+
+% Create the algorithm object from the configuration structure
+alg_id = astra_mex_algorithm('create', cfg);
+
+% Run 20 iterations of the algorithm
+% This will have a runtime in the order of 10 seconds.
+astra_mex_algorithm('iterate', alg_id, 20);
+
+% Get the result
+rec = astra_mex_data2d('get', rec_id);
+figure(3); imshow(rec, []);
+
+% Clean up. 
+astra_mex_projector('delete', proj_id);
+astra_mex_algorithm('delete', alg_id);
+astra_mex_data2d('delete', rec_id);
+astra_mex_data2d('delete', sinogram_id);
diff --git a/samples/matlab/s005_3d_geometry.m b/samples/matlab/s005_3d_geometry.m
new file mode 100644
index 0000000..4b7360b
--- /dev/null
+++ b/samples/matlab/s005_3d_geometry.m
@@ -0,0 +1,98 @@
+% -----------------------------------------------------------------------
+% This file is part of the ASTRA Toolbox
+% 
+% Copyright: 2010-2015, iMinds-Vision Lab, University of Antwerp
+%            2014-2015, CWI, Amsterdam
+% License: Open Source under GPLv3
+% Contact: astra@uantwerpen.be
+% Website: http://sf.net/projects/astra-toolbox
+% -----------------------------------------------------------------------
+
+vol_geom = astra_create_vol_geom(64, 64, 64);
+
+
+% There are two main 3d projection geometry types: cone beam and parallel beam.
+% Each has a regular variant, and a 'vec' variant.
+% The 'vec' variants are completely free in the placement of source/detector,
+% while the regular variants assume circular trajectories around the z-axis.
+
+
+% -------------
+% Parallel beam
+% -------------
+
+
+% Circular
+
+% Parameters: width of detector column, height of detector row, #rows, #columns
+angles = linspace2(0, 2*pi, 48);
+proj_geom = astra_create_proj_geom('parallel3d', 1.0, 1.0, 32, 64, angles);
+
+
+% Free
+
+% We generate the same geometry as the circular one above. 
+vectors = zeros(numel(angles), 12);
+for i = 1:numel(angles)
+  % ray direction
+  vectors(i,1) = sin(angles(i));
+  vectors(i,2) = -cos(angles(i));
+  vectors(i,3) = 0;	
+
+  % center of detector
+  vectors(i,4:6) = 0;
+
+  % vector from detector pixel (0,0) to (0,1)
+  vectors(i,7) = cos(angles(i));
+  vectors(i,8) = sin(angles(i));
+  vectors(i,9) = 0;
+
+  % vector from detector pixel (0,0) to (1,0)
+  vectors(i,10) = 0;
+  vectors(i,11) = 0;
+  vectors(i,12) = 1;
+end
+
+% Parameters: #rows, #columns, vectors
+proj_geom = astra_create_proj_geom('parallel3d_vec', 32, 64, vectors);
+
+% ----------
+% Cone beam
+% ----------
+
+
+% Circular
+
+% Parameters: width of detector column, height of detector row, #rows, #columns,
+%             angles, distance source-origin, distance origin-detector
+angles = linspace2(0, 2*pi, 48);
+proj_geom = astra_create_proj_geom('cone', 1.0, 1.0, 32, 64, ...
+                                   angles, 1000, 0);
+
+% Free
+
+vectors = zeros(numel(angles), 12);
+for i = 1:numel(angles)
+
+	% source
+	vectors(i,1) = sin(angles(i)) * 1000;
+	vectors(i,2) = -cos(angles(i)) * 1000;
+	vectors(i,3) = 0;	
+
+	% center of detector
+	vectors(i,4:6) = 0;
+
+	% vector from detector pixel (0,0) to (0,1)
+	vectors(i,7) = cos(angles(i));
+	vectors(i,8) = sin(angles(i));
+	vectors(i,9) = 0;
+
+	% vector from detector pixel (0,0) to (1,0)
+	vectors(i,10) = 0;
+	vectors(i,11) = 0;
+	vectors(i,12) = 1;		
+end
+
+% Parameters: #rows, #columns, vectors
+proj_geom = astra_create_proj_geom('cone_vec', 32, 64, vectors);
+
diff --git a/samples/matlab/s006_3d_data.m b/samples/matlab/s006_3d_data.m
new file mode 100644
index 0000000..32d88cc
--- /dev/null
+++ b/samples/matlab/s006_3d_data.m
@@ -0,0 +1,62 @@
+% -----------------------------------------------------------------------
+% This file is part of the ASTRA Toolbox
+% 
+% Copyright: 2010-2015, iMinds-Vision Lab, University of Antwerp
+%            2014-2015, CWI, Amsterdam
+% License: Open Source under GPLv3
+% Contact: astra@uantwerpen.be
+% Website: http://sf.net/projects/astra-toolbox
+% -----------------------------------------------------------------------
+
+% Create a 3D volume geometry.
+% Parameter order: rows, colums, slices (y, x, z)
+vol_geom = astra_create_vol_geom(64, 48, 32);
+
+
+% Create volumes
+
+% initialized to zero
+v0 = astra_mex_data3d('create', '-vol', vol_geom);
+
+% initialized to 3.0
+v1 = astra_mex_data3d('create', '-vol', vol_geom, 3.0);
+
+% initialized to a matrix. A may be a single or double array.
+% Coordinate order: column, row, slice (x, y, z)
+A = zeros(48, 64, 32);
+v2 = astra_mex_data3d('create', '-vol', vol_geom, A);
+
+
+% Projection data
+
+% 2 projection directions, along x and y axis resp.
+V = [ 1 0 0  0 0 0   0 1 0  0 0 1 ; ...
+      0 1 0  0 0 0  -1 0 0  0 0 1 ];
+% 32 rows (v), 64 columns (u)
+proj_geom = astra_create_proj_geom('parallel3d_vec', 32, 64, V);
+
+s0 = astra_mex_data3d('create', '-proj3d', proj_geom);
+
+% Initialization to a scalar or zero works exactly as with a volume.
+
+% Initialized to a matrix:
+% Coordinate order: column (u), angle, row (v)
+A = zeros(64, 2, 32);
+s1 = astra_mex_data3d('create', '-proj3d', proj_geom, A);
+
+
+% Retrieve data:
+R = astra_mex_data3d('get', v1);
+
+% Retrieve data as a single array. Since astra internally stores
+% data as single precision, this is more efficient:
+R = astra_mex_data3d('get_single', v1);
+
+
+
+% Delete all created data objects
+astra_mex_data3d('delete', v0);
+astra_mex_data3d('delete', v1);
+astra_mex_data3d('delete', v2);
+astra_mex_data3d('delete', s0);
+astra_mex_data3d('delete', s1);
diff --git a/samples/matlab/s007_3d_reconstruction.m b/samples/matlab/s007_3d_reconstruction.m
new file mode 100644
index 0000000..fc9aca6
--- /dev/null
+++ b/samples/matlab/s007_3d_reconstruction.m
@@ -0,0 +1,53 @@
+% -----------------------------------------------------------------------
+% This file is part of the ASTRA Toolbox
+% 
+% Copyright: 2010-2015, iMinds-Vision Lab, University of Antwerp
+%            2014-2015, CWI, Amsterdam
+% License: Open Source under GPLv3
+% Contact: astra@uantwerpen.be
+% Website: http://sf.net/projects/astra-toolbox
+% -----------------------------------------------------------------------
+
+vol_geom = astra_create_vol_geom(128, 128, 128);
+
+angles = linspace2(0, pi, 180);
+proj_geom = astra_create_proj_geom('parallel3d', 1.0, 1.0, 128, 192, angles);
+
+% Create a simple hollow cube phantom
+cube = zeros(128,128,128);
+cube(17:112,17:112,17:112) = 1;
+cube(33:96,33:96,33:96) = 0;
+
+% Create projection data from this
+[proj_id, proj_data] = astra_create_sino3d_cuda(cube, proj_geom, vol_geom);
+
+% Display a single projection image
+figure, imshow(squeeze(proj_data(:,20,:))',[])
+
+% Create a data object for the reconstruction
+rec_id = astra_mex_data3d('create', '-vol', vol_geom);
+
+% Set up the parameters for a reconstruction algorithm using the GPU
+cfg = astra_struct('SIRT3D_CUDA');
+cfg.ReconstructionDataId = rec_id;
+cfg.ProjectionDataId = proj_id;
+
+
+% Create the algorithm object from the configuration structure
+alg_id = astra_mex_algorithm('create', cfg);
+
+% Run 150 iterations of the algorithm
+% Note that this requires about 750MB of GPU memory, and has a runtime
+% in the order of 10 seconds.
+astra_mex_algorithm('iterate', alg_id, 150);
+
+% Get the result
+rec = astra_mex_data3d('get', rec_id);
+figure, imshow(squeeze(rec(:,:,65)),[]);
+
+
+% 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_data3d('delete', rec_id);
+astra_mex_data3d('delete', proj_id);
diff --git a/samples/matlab/s008_gpu_selection.m b/samples/matlab/s008_gpu_selection.m
new file mode 100644
index 0000000..a9e152d
--- /dev/null
+++ b/samples/matlab/s008_gpu_selection.m
@@ -0,0 +1,37 @@
+% -----------------------------------------------------------------------
+% This file is part of the ASTRA Toolbox
+% 
+% Copyright: 2010-2015, iMinds-Vision Lab, University of Antwerp
+%            2014-2015, CWI, Amsterdam
+% License: Open Source under GPLv3
+% Contact: astra@uantwerpen.be
+% Website: http://sf.net/projects/astra-toolbox
+% -----------------------------------------------------------------------
+
+vol_geom = astra_create_vol_geom(256, 256);
+proj_geom = astra_create_proj_geom('parallel', 1.0, 384, linspace2(0,pi,180));
+P = phantom(256);
+
+% Create a sinogram from a phantom, using GPU #1. (The default is #0)
+[sinogram_id, sinogram] = astra_create_sino_gpu(P, proj_geom, vol_geom, 1);
+
+
+% Set up the parameters for a reconstruction algorithm using the GPU
+rec_id = astra_mex_data2d('create', '-vol', vol_geom);
+cfg = astra_struct('SIRT_CUDA');
+cfg.ReconstructionDataId = rec_id;
+cfg.ProjectionDataId = sinogram_id;
+
+% Use GPU #1 for the reconstruction. (The default is #0.)
+cfg.option.GPUindex = 1;
+
+% Run 150 iterations of the algorithm
+alg_id = astra_mex_algorithm('create', cfg);
+astra_mex_algorithm('iterate', alg_id, 150);
+rec = astra_mex_data2d('get', rec_id);
+
+
+% Clean up.
+astra_mex_algorithm('delete', alg_id);
+astra_mex_data2d('delete', rec_id);
+astra_mex_data2d('delete', sinogram_id);
diff --git a/samples/matlab/s009_projection_matrix.m b/samples/matlab/s009_projection_matrix.m
new file mode 100644
index 0000000..efda0d2
--- /dev/null
+++ b/samples/matlab/s009_projection_matrix.m
@@ -0,0 +1,45 @@
+% -----------------------------------------------------------------------
+% This file is part of the ASTRA Toolbox
+% 
+% Copyright: 2010-2015, iMinds-Vision Lab, University of Antwerp
+%            2014-2015, CWI, Amsterdam
+% License: Open Source under GPLv3
+% Contact: astra@uantwerpen.be
+% Website: http://sf.net/projects/astra-toolbox
+% -----------------------------------------------------------------------
+
+vol_geom = astra_create_vol_geom(256, 256);
+proj_geom = astra_create_proj_geom('parallel', 1.0, 384, linspace2(0,pi,180));
+
+% For CPU-based algorithms, a "projector" object specifies the projection
+% model used. In this case, we use the "strip" model.
+proj_id = astra_create_projector('strip', proj_geom, vol_geom);
+
+% Generate the projection matrix for this projection model.
+% This creates a matrix W where entry w_{i,j} corresponds to the
+% contribution of volume element j to detector element i.
+matrix_id = astra_mex_projector('matrix', proj_id);
+
+% Get the projection matrix as a Matlab sparse matrix.
+W = astra_mex_matrix('get', matrix_id);
+
+
+% Manually use this projection matrix to do a projection:
+P = phantom(256)';
+s = W * P(:);
+s = reshape(s, [proj_geom.DetectorCount size(proj_geom.ProjectionAngles, 2)])';
+figure(1), imshow(s,[]);
+
+% Because Matlab's matrices are stored transposed in memory compared to C++,
+% reshaping them to a vector doesn't give the right ordering for multiplication
+% with W. We have to take the transpose of the input and output to get the same
+% results (up to numerical noise) as using the toolbox directly.
+
+% Each row of the projection matrix corresponds to a detector element.
+% Detector t for angle p is for row 1 + t + p*proj_geom.DetectorCount.
+% Each column corresponds to a volume pixel.
+% Pixel (x,y) corresponds to column 1 + x + y*vol_geom.GridColCount.
+
+
+astra_mex_projector('delete', proj_id);
+astra_mex_matrix('delete', matrix_id);
diff --git a/samples/matlab/s010_supersampling.m b/samples/matlab/s010_supersampling.m
new file mode 100644
index 0000000..80f6f56
--- /dev/null
+++ b/samples/matlab/s010_supersampling.m
@@ -0,0 +1,58 @@
+% -----------------------------------------------------------------------
+% This file is part of the ASTRA Toolbox
+% 
+% Copyright: 2010-2015, iMinds-Vision Lab, University of Antwerp
+%            2014-2015, CWI, Amsterdam
+% License: Open Source under GPLv3
+% Contact: astra@uantwerpen.be
+% Website: http://sf.net/projects/astra-toolbox
+% -----------------------------------------------------------------------
+
+vol_geom = astra_create_vol_geom(256, 256);
+proj_geom = astra_create_proj_geom('parallel', 3.0, 128, linspace2(0,pi,180));
+P = phantom(256);
+
+% Because the astra_create_sino_gpu wrapper does not have support for
+% all possible algorithm options, we manually create a sinogram
+phantom_id = astra_mex_data2d('create', '-vol', vol_geom, P);
+sinogram_id = astra_mex_data2d('create', '-sino', proj_geom);
+cfg = astra_struct('FP_CUDA');
+cfg.VolumeDataId = phantom_id;
+cfg.ProjectionDataId = sinogram_id;
+
+% Set up 3 rays per detector element
+cfg.option.DetectorSuperSampling = 3;
+
+alg_id = astra_mex_algorithm('create', cfg);
+astra_mex_algorithm('run', alg_id);
+astra_mex_algorithm('delete', alg_id);
+astra_mex_data2d('delete', phantom_id);
+
+sinogram3 = astra_mex_data2d('get', sinogram_id);
+
+figure(1); imshow(P, []);
+figure(2); imshow(sinogram3, []);
+
+
+% Create a reconstruction, also using supersampling
+rec_id = astra_mex_data2d('create', '-vol', vol_geom);
+cfg = astra_struct('SIRT_CUDA');
+cfg.ReconstructionDataId = rec_id;
+cfg.ProjectionDataId = sinogram_id;
+% Set up 3 rays per detector element
+cfg.option.DetectorSuperSampling = 3;
+
+% There is also an option for supersampling during the backprojection step.
+% This should be used if your detector pixels are smaller than the voxels.
+
+% Set up 2 rays per image pixel dimension, for 4 rays total per image pixel.
+% cfg.option.PixelSuperSampling = 2;
+
+
+alg_id = astra_mex_algorithm('create', cfg);
+astra_mex_algorithm('iterate', alg_id, 150);
+astra_mex_algorithm('delete', alg_id);
+
+rec = astra_mex_data2d('get', rec_id);
+figure(3); imshow(rec, []);
+
diff --git a/samples/matlab/s011_object_info.m b/samples/matlab/s011_object_info.m
new file mode 100644
index 0000000..61ecb83
--- /dev/null
+++ b/samples/matlab/s011_object_info.m
@@ -0,0 +1,36 @@
+% -----------------------------------------------------------------------
+% This file is part of the ASTRA Toolbox
+% 
+% Copyright: 2010-2015, iMinds-Vision Lab, University of Antwerp
+%            2014-2015, CWI, Amsterdam
+% License: Open Source under GPLv3
+% Contact: astra@uantwerpen.be
+% Website: http://sf.net/projects/astra-toolbox
+% -----------------------------------------------------------------------
+
+% Create two volume geometries
+vol_geom1 = astra_create_vol_geom(256, 256);
+vol_geom2 = astra_create_vol_geom(512, 256);
+
+% Create volumes
+v0 = astra_mex_data2d('create', '-vol', vol_geom1);
+v1 = astra_mex_data2d('create', '-vol', vol_geom2);
+v2 = astra_mex_data2d('create', '-vol', vol_geom2);
+
+% Show the currently allocated volumes
+astra_mex_data2d('info');
+
+
+astra_mex_data2d('delete', v2);
+astra_mex_data2d('info');
+
+astra_mex_data2d('clear');
+astra_mex_data2d('info');
+
+
+
+% The same clear and info command also work for other object types:
+astra_mex_algorithm('info');
+astra_mex_data3d('info');
+astra_mex_projector('info');
+astra_mex_matrix('info');
diff --git a/samples/matlab/s012_masks.m b/samples/matlab/s012_masks.m
new file mode 100644
index 0000000..d3611a6
--- /dev/null
+++ b/samples/matlab/s012_masks.m
@@ -0,0 +1,60 @@
+% -----------------------------------------------------------------------
+% This file is part of the ASTRA Toolbox
+% 
+% Copyright: 2010-2015, iMinds-Vision Lab, University of Antwerp
+%            2014-2015, CWI, Amsterdam
+% License: Open Source under GPLv3
+% Contact: astra@uantwerpen.be
+% Website: http://sf.net/projects/astra-toolbox
+% -----------------------------------------------------------------------
+
+
+% 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);
diff --git a/samples/matlab/s013_constraints.m b/samples/matlab/s013_constraints.m
new file mode 100644
index 0000000..d72195c
--- /dev/null
+++ b/samples/matlab/s013_constraints.m
@@ -0,0 +1,47 @@
+% -----------------------------------------------------------------------
+% This file is part of the ASTRA Toolbox
+% 
+% Copyright: 2010-2015, iMinds-Vision Lab, University of Antwerp
+%            2014-2015, CWI, Amsterdam
+% License: Open Source under GPLv3
+% Contact: astra@uantwerpen.be
+% Website: http://sf.net/projects/astra-toolbox
+% -----------------------------------------------------------------------
+
+% In this example we will create a reconstruction constrained to
+% greyvalues between 0 and 1
+
+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(1); imshow(P, []);
+figure(2); imshow(sinogram, []);
+
+% Create a data object for the reconstruction
+rec_id = astra_mex_data2d('create', '-vol', vol_geom);
+
+% 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.MinConstraint = 0;
+cfg.option.MaxConstraint = 1;
+
+% 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(3); 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', rec_id);
+astra_mex_data2d('delete', sinogram_id);
diff --git a/samples/matlab/s014_FBP.m b/samples/matlab/s014_FBP.m
new file mode 100644
index 0000000..b73149c
--- /dev/null
+++ b/samples/matlab/s014_FBP.m
@@ -0,0 +1,47 @@
+% -----------------------------------------------------------------------
+% This file is part of the ASTRA Toolbox
+% 
+% Copyright: 2010-2015, iMinds-Vision Lab, University of Antwerp
+%            2014-2015, CWI, Amsterdam
+% License: Open Source under GPLv3
+% Contact: astra@uantwerpen.be
+% Website: http://sf.net/projects/astra-toolbox
+% -----------------------------------------------------------------------
+
+vol_geom = astra_create_vol_geom(256, 256);
+proj_geom = astra_create_proj_geom('parallel', 1.0, 384, linspace2(0,pi,180));
+
+% As before, create a sinogram from a phantom
+P = phantom(256);
+[sinogram_id, sinogram] = astra_create_sino_gpu(P, proj_geom, vol_geom);
+figure(1); imshow(P, []);
+figure(2); imshow(sinogram, []);
+
+% Create a data object for the reconstruction
+rec_id = astra_mex_data2d('create', '-vol', vol_geom);
+
+% create configuration 
+cfg = astra_struct('FBP_CUDA');
+cfg.ReconstructionDataId = rec_id;
+cfg.ProjectionDataId = sinogram_id;
+cfg.FilterType = 'Ram-Lak';
+
+% possible values for FilterType:
+% none, ram-lak, shepp-logan, cosine, hamming, hann, tukey, lanczos,
+% triangular, gaussian, barlett-hann, blackman, nuttall, blackman-harris,
+% blackman-nuttall, flat-top, kaiser, parzen
+
+
+% Create and run the algorithm object from the configuration structure
+alg_id = astra_mex_algorithm('create', cfg);
+astra_mex_algorithm('run', alg_id);
+
+% Get the result
+rec = astra_mex_data2d('get', rec_id);
+figure(3); 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', rec_id);
+astra_mex_data2d('delete', sinogram_id);
diff --git a/samples/matlab/s015_fp_bp.m b/samples/matlab/s015_fp_bp.m
new file mode 100644
index 0000000..8cc417e
--- /dev/null
+++ b/samples/matlab/s015_fp_bp.m
@@ -0,0 +1,62 @@
+% -----------------------------------------------------------------------
+% This file is part of the ASTRA Toolbox
+% 
+% Copyright: 2010-2015, iMinds-Vision Lab, University of Antwerp
+%            2014-2015, CWI, Amsterdam
+% License: Open Source under GPLv3
+% Contact: astra@uantwerpen.be
+% Website: http://sf.net/projects/astra-toolbox
+% -----------------------------------------------------------------------
+
+
+% This example demonstrates using the FP and BP primitives with Matlab's lsqr
+% solver. Calls to FP (astra_create_sino_cuda) and
+% BP (astra_create_backprojection_cuda) are wrapped in a function astra_wrap,
+% and a handle to this function is passed to lsqr.
+
+% Because in this case the inputs/outputs of FP and BP have to be vectors
+% instead of images (matrices), the calls require reshaping to and from vectors.
+
+function s015_fp_bp
+
+
+% FP/BP wrapper function
+function Y = astra_wrap(X,T)
+  if strcmp(T, 'notransp')
+    % X is passed as a vector. Reshape it into an image.
+    [sid, s] = astra_create_sino_cuda(reshape(X,[vol_geom.GridRowCount vol_geom.GridColCount])', proj_geom, vol_geom);
+    astra_mex_data2d('delete', sid);
+    % now s is the sinogram. Reshape it back into a vector
+    Y = reshape(s',[prod(size(s)) 1]);
+  else
+    % X is passed as a vector. Reshape it into a sinogram.
+    v = astra_create_backprojection_cuda(reshape(X, [proj_geom.DetectorCount size(proj_geom.ProjectionAngles,2)])', proj_geom, vol_geom);
+    % now v is the resulting volume. Reshape it back into a vector
+    Y = reshape(v',[prod(size(v)) 1]);
+  end
+end
+
+
+vol_geom = astra_create_vol_geom(256, 256);
+proj_geom = astra_create_proj_geom('parallel', 1.0, 384, linspace2(0,pi,180));
+
+% Create a 256x256 phantom image using matlab's built-in phantom() function
+P = phantom(256);
+
+% Create a sinogram using the GPU.
+[sinogram_id, sinogram] = astra_create_sino_gpu(P, proj_geom, vol_geom);
+
+% Reshape the sinogram into a vector
+b = reshape(sinogram',[prod(size(sinogram)) 1]);
+
+% Call Matlab's lsqr with ASTRA FP and BP
+Y = lsqr(@astra_wrap,b,1e-4,25);
+
+% Reshape the result into an image
+Y = reshape(Y,[vol_geom.GridRowCount vol_geom.GridColCount])';
+imshow(Y,[]);
+
+
+astra_mex_data2d('delete', sinogram_id);
+
+end
diff --git a/samples/matlab/s016_plots.m b/samples/matlab/s016_plots.m
new file mode 100644
index 0000000..1455c6d
--- /dev/null
+++ b/samples/matlab/s016_plots.m
@@ -0,0 +1,54 @@
+% -----------------------------------------------------------------------
+% This file is part of the ASTRA Toolbox
+% 
+% Copyright: 2010-2015, iMinds-Vision Lab, University of Antwerp
+%            2014-2015, CWI, Amsterdam
+% License: Open Source under GPLv3
+% Contact: astra@uantwerpen.be
+% Website: http://sf.net/projects/astra-toolbox
+% -----------------------------------------------------------------------
+
+vol_geom = astra_create_vol_geom(256, 256);
+proj_geom = astra_create_proj_geom('parallel', 1.0, 384, linspace2(0,pi,180));
+
+% As before, create a sinogram from a phantom
+P = phantom(256);
+[sinogram_id, sinogram] = astra_create_sino_gpu(P, proj_geom, vol_geom);
+figure(1); imshow(P, []);
+figure(2); imshow(sinogram, []);
+
+% Create a data object for the reconstruction
+rec_id = astra_mex_data2d('create', '-vol', vol_geom);
+
+% Set up the parameters for a reconstruction algorithm using the GPU
+cfg = astra_struct('SIRT_CUDA');
+cfg.ReconstructionDataId = rec_id;
+cfg.ProjectionDataId = sinogram_id;
+
+% Create the algorithm object from the configuration structure
+alg_id = astra_mex_algorithm('create', cfg);
+
+% Run 1500 iterations of the algorithm one at a time, keeping track of errors
+nIters = 1500;
+phantom_error = zeros(1, nIters);
+residual_error = zeros(1, nIters);
+for i = 1:nIters;
+  % Run a single iteration
+  astra_mex_algorithm('iterate', alg_id, 1);
+
+  residual_error(i) = astra_mex_algorithm('get_res_norm', alg_id);
+  rec = astra_mex_data2d('get', rec_id);
+  phantom_error(i) = sqrt(sumsqr(rec - P));
+end
+
+% Get the result
+rec = astra_mex_data2d('get', rec_id);
+figure(3); imshow(rec, []);
+
+figure(4); plot(residual_error)
+figure(5); plot(phantom_error)
+
+% Clean up.
+astra_mex_algorithm('delete', alg_id);
+astra_mex_data2d('delete', rec_id);
+astra_mex_data2d('delete', sinogram_id);