Added DeviceModel and AstraDevice

these classes are to abstract the calls to forward/backprojection so that
the FISTA implementation is independent of ASTRA and we may use CCPi code
from CGLS.

2 files changed, 124 insertions, 0 deletions

diff --git a/src/Python/ccpi/reconstruction/AstraDevice.py b/src/Python/ccpi/reconstruction/AstraDevice.py
new file mode 100644
index 0000000..d854183
--- /dev/null
+++ b/src/Python/ccpi/reconstruction/AstraDevice.py
@@ -0,0 +1,67 @@
+import astra
+from DeviceModel import DeviceModel
+
+class AstraDevice(DeviceModel):
+    '''Concrete class for Astra Device'''
+
+    def __init__(self,
+                 device_type,
+                 data_aquisition_geometry,
+                 reconstructed_volume_geometry):
+        
+
+        self.proj_geom = astra.creators.create_proj_geom(
+            device_type,
+            self.acquisition_data_geometry['detectorSpacingX'],
+            self.acquisition_data_geometry['detectorSpacingX'],
+            self.acquisition_data_geometry['cameraX'],
+            self.acquisition_data_geometry['cameraY'],
+            self.acquisition_data_geometry['angles'],
+            angles_rad
+            )
+
+        self.vol_geom = astra.creators.create_vol_geom(
+            self.reconstructed_volume_geometry['X'],
+            self.reconstructed_volume_geometry['Y'],
+            self.reconstructed_volume_geometry['Z']
+            )
+
+    def doForwardProject(self, volume):
+        '''Forward projects the volume according to the device geometry
+
+Uses Astra-toolbox
+'''
+        sino_id, y = astra.creators.create_sino3d_gpu(
+            volume, self.proj_geom, self.vol_geom)
+        astra.matlab.data3d('delete', sino_id)
+        return y
+
+    def doBackwardProject(self, projections):
+        '''Backward projects the projections according to the device geometry
+
+Uses Astra-toolbox
+'''
+        idx, volume = \
+               astra.creators.create_backprojection3d_gpu(
+                   projections,
+                   self.proj_geom,
+                   self.vol_geom)
+        astra.matlab.data3d('delete', idx)
+        return volume
+
+    def createReducedDevice(self):
+        return AstraDevice(self.proj_geom['type'],
+                    {'detectorSpacingX' : self.proj_geom['DetectorSpacingX'] ,
+                     'detectorSpacingY' : self.proj_geom['DetectorSpacingY'] ,
+                     'cameraX' : self.proj_geom['DetectorColCount'] ,
+                     'cameraY' : 1 ,
+                     'angles' : self.proj_geom['ProjectionAngles'] } ,
+                    {
+                        'X' : self.vol_geom['GridColCount'],
+                        'Y' : self.vol_geom['GridRowCount']
+                        'Z' : 1} ) 
+
+if __name__=="main":
+    a = AstraDevice()
+
+
diff --git a/src/Python/ccpi/reconstruction/DeviceModel.py b/src/Python/ccpi/reconstruction/DeviceModel.py
new file mode 100644
index 0000000..1717321
--- /dev/null
+++ b/src/Python/ccpi/reconstruction/DeviceModel.py
@@ -0,0 +1,57 @@
+from abc import ABCMeta, abstractmethod
+from enum import Enum
+
+class DeviceModel(metaclass=ABCMeta):
+    '''Abstract class that defines the device for projection and backprojection
+
+This class defines the methods that must be implemented by concrete classes.
+
+    '''
+    
+    class DeviceType(Enum):
+        '''Type of device
+PARALLEL BEAM
+PARALLEL BEAM 3D
+CONE BEAM
+HELICAL'''
+        
+        PARALLEL = 'parallel'
+        PARALLEL3D = 'parallel3d'
+        CONE_BEAM = 'cone-beam'
+        HELICAL = 'helical'
+        
+    def __init__(self,
+                 device_type,
+                 data_aquisition_geometry,
+                 reconstructed_volume_geometry):
+        '''Initializes the class
+
+Mandatory parameters are:
+device_type from DeviceType Enum
+data_acquisition_geometry: tuple (camera_X, camera_Y)
+reconstructed_volume_geometry: tuple (dimX,dimY,dimZ)
+'''
+        self.device_geometry = device_type
+        self.acquisition_data_geometry = {
+            'cameraX':           data_aquisition_geometry[0],
+            'cameraY':           data_aquisition_geometry[1],
+            'detectorSpacingX' : data_aquisition_geometry[2],
+            'detectorSpacingY' : data_aquisition_geometry[3],
+            'angles' :           data_aquisition_geometry[4],}
+        self.reconstructed_volume_geometry = {
+            'X': reconstructed_volume_geometry[0] ,
+            'Y': reconstructed_volume_geometry[1] ,
+            'Z': reconstructed_volume_geometry[2] }
+
+    @abstractmethod
+    def doFowardProject(self, volume):
+        '''Forward projects the volume according to the device geometry'''
+        return NotImplemented
+
+    
+    @abstractmethod
+    def doBackwardProject(self, projections):
+        '''Backward projects the projections according to the device geometry'''
+        return NotImplemented
+    
+