Get Image

Overview

This input file (GetImage.in) is used to run and define the parameters of the plugin GmGetImage.cc. The parameters defined in this input file are related with the image formation and detector characteristics.

Step-by-Step Instructions

Users can modify a lot of parameters in order to obtain the desired output from the simulation.

1. Detector Parameters.

  • GetImage:NumPixels(X/Y): Command to set the number of pixels in each direction.

  • GetImage:PixelSizeX: Command to set the pixel size in each direction (in mm).

  • GetImage:zStop: Is the distance from the the origin to the detector (in mm).

  • GetImage:DetectorModel: Users can select between MCD or VD detector models.

    • MCD (Monte Carlo Detector): It uses a Geant4-solid box as a detector. All interactions inside the detector are simulated through the cross sections used by Geant4. The final output is a file with the energy deposited in each pixel by the hits.

    • VD (Virtual Detector): It uses a virtual plane as a detector. The interactions are simulated through an efficiency curve located in plug-ins/resources/. The output is the energy deposited in each pixel.

  • GetImage:OutputType: Users can select between two different outputs, Energy or Charge. We recommend to select the Energy output and modify the output using the image formation GUI’s module.

  • GetImage:ResultsFolder: The folder where the output is saved.

  • GetImage:OutputFilename: The filename of the output.

  • GetImage:OutputFormat: The format of the output. The format can be DICOM, MHD/RAW or Text.

2.Anti-scatter grid.

The anti-scatter grid is a focussed grid modeled following the steps of Day and Dance [3] and tha name of the parameters correspond with the names given in the reference.

  • Grid:UseGrid: If Yes, an anti-scatter grid will be used in the simulation. If No, it won’t.

  • Grid:Ratio: It is the ratio between the height of the stips and the thickness of the interspace region.

  • Grid:SourceDetectorDistance: Distance (in mm) Source-Detector.

  • Grid:Frequency: The frequency iof the strip bars (in 1/mm).

  • Grid:StripThickness: Thicknes (in mm) of the lead’s strip.

  • Grid:Gap: It is the position of the source in the X-direction.

Example:

 1########################
 2# DETECTOR MODEL SETUP #
 3########################
 4
 5# Virtual detector segmentation
 6#/gamos/setParam SD:VirtSegmBox:NDiv:Absorber 1765.0 1765.0 1.
 7#/gamos/setParam SD:VirtSegmBox:Width:Absorber 150.025 150.025 0.2
 8#/gamos/SD/assocSD2LogVol GmSDVirtSegmBox Absorber detector
 9#/gamos/SD/recHitBuilder GmRecHitBuilderBydose Absorber
10
11/gamos/setParam GetImage:NumPixelsX 1765.0
12/gamos/setParam GetImage:NumPixelsY 1765.0
13/gamos/setParam GetImage:PixelSizeX 0.085
14/gamos/setParam GetImage:PixelSizeY 0.085
15/gamos/setParam GetImage:zStop 648.9
16#/gamos/setParam GetImage:PairCreationEnergy 50.0
17
18################
19# OUTPUT SETUP #
20################
21
22/gamos/setParam GetImage:DetectorModel VD
23/gamos/setParam GetImage:OutputType Charge
24/gamos/setParam GetImage:ResultsFolder output/
25/gamos/setParam GetImage:OutputFilename test
26/gamos/setParam GetImage:OutputFormat MHD/RAW
27
28#####################
29# ANTI-SCATTER GRID #
30#####################
31
32/gamos/setParam Grid:UseGrid Yes
33/gamos/setParam Grid:Ratio 5.0
34/gamos/setParam Grid:SourceDetectorDistance 648.9
35/gamos/setParam Grid:Frequency 3.1
36/gamos/setParam Grid:StripThickness 0.065
37/gamos/setParam Grid:Gap -75.0125
38
39####################
40# USER ACTION CALL #
41####################
42
43/gamos/userAction GmGetImage