Demo 01: Describing your geometry

To see a demo of what the geometry paramterers should look like, do as follows:



In [1]:

    
import tigre
geo = tigre.geometry_default(high_quality = False)
print(geo)









    



TIGRE parameters
-----
Geometry parameters
Distance from source to detector (DSD) = 1536 mm
Distance from source to origin (DSO)= 1000 mm
-----
Detector parameters
Number of pixels (nDetector) = [128 128]
Size of each pixel (dDetector) = [3.2 3.2] mm
Total size of the detector (sDetector) = [409.6 409.6] mm
-----
Image parameters
Number of voxels (nVoxel) = [64 64 64]
Total size of the image (sVoxel) = [256 256 256] mm
Size of each voxel (dVoxel) = [4. 4. 4.] mm
-----
Offset correction parameters
Offset of image from origin (offOrigin) = [0 0 0] mm
Offset of detector (offDetector) = [0 0] mm
-----
Auxillary parameters
Samples per pixel of forward projection (accuracy) = 0.5
-----
Rotation of the Detector (rotDetector) = [0 0 0] rad

We recommend using the template below and defining you're class as such:



In [ ]:

    
from __future__ import division
import numpy as np


class Geometry:

    def __init__(self, high_quality=True):
        if high_quality:
            # VARIABLE                                          DESCRIPTION                    UNITS
            # -------------------------------------------------------------------------------------
            self.DSD = 1536                                     # Distance Source Detector      (mm)
            self.DSO = 1000                                     # Distance Source Origin        (mm)
            # Detector parameters
            self.nDetector = np.array((512, 512))               # number of pixels              (px)
            self.dDetector = np.array((0.8, 0.8))               # size of each pixel            (mm)
            self.sDetector = self.nDetector * self.dDetector    # total size of the detector    (mm)
            # Image parameters
            self.nVoxel = np.array((256, 256, 256))             # number of voxels              (vx)
            self.sVoxel = np.array((256, 256, 256))             # total size of the image       (mm)
            self.dVoxel = self.sVoxel/self.nVoxel               # size of each voxel            (mm)
            # Offsets
            self.offOrigin = np.array((0, 0, 0))                # Offset of image from origin   (mm)
            self.offDetector = np.array((0, 0))                 # Offset of Detector            (mm)

            # Auxiliary
            self.accuracy = 0.5                                 # Accuracy of FWD proj          (vx/sample)
            # Mode
            self.mode = 'cone'                                  # parallel, cone                ...
        else:
            # VARIABLE                                          DESCRIPTION                    UNITS
            # -------------------------------------------------------------------------------------
            self.DSD = 1536                                     # Distance Source Detector      (mm)
            self.DSO = 1000                                     # Distance Source Origin        (mm)
            # Detector parameters
            self.nDetector = np.array((128, 128))             # number of pixels              (px)
            self.dDetector = np.array((0.8, 0.8))*4             # size of each pixel            (mm)
            self.sDetector = self.nDetector * self.dDetector    # total size of the detector    (mm)
            # Image parameters
            self.nVoxel = np.array((64, 64 , 64))           # number of voxels              (vx)
            self.sVoxel = np.array((256, 256, 256))             # total size of the image       (mm)
            self.dVoxel = self.sVoxel / self.nVoxel             # size of each voxel            (mm)
            # Offsets
            self.offOrigin = np.array((0, 0, 0))                # Offset of image from origin   (mm)
            self.offDetector = np.array((0, 0))                 # Offset of Detector            (mm)

            # Auxiliary
            self.accuracy = 0.5                                 # Accuracy of FWD proj          (vx/sample)
            # Mode
            self.mode=None                                      # parallel, cone                ...
            self.filter=None