detector

Set up the 7 degrees-of-freedom parameters for the C-arm

Tip

The Detector is usually initialized in the DRR module and shouldn’t need to be called directly.

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Detector

def Detector(
    sdd:float, # Source-to-detector distance (in units length)
    height:int, # Y-direction length (in units pixels)
    width:int, # X-direction length (in units pixels)
    delx:float, # X-direction spacing (in units length / pixel)
    dely:float, # Y-direction spacing (in units length / pixel)
    x0:float, # Principal point x-coordinate (in units length)
    y0:float, # Principal point y-coordinate (in units length)
    reorient:torch.Tensor, # Frame-of-reference change matrix
    n_subsample:int | None=None, # Number of target points to randomly sample
    reverse_x_axis:bool=False, # If pose includes reflection (in E(3) not SE(3)), reverse x-axis
):

Construct a 6 DoF X-ray detector system. This model is based on a C-Arm.

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Detector.forward

def forward(
    extrinsic:RigidTransform, calibration:RigidTransform
):

Create source and target points for X-rays to trace through the volume.

Intrinsic matrix parsing

From a calibrated camera’s intrinsic matrix, calculate the following properties:

• Focal length (in units length)
• Principal point (in units length)

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get_focal_length

def get_focal_length(
    intrinsic, # Intrinsic matrix (3 x 3 tensor)
    delx:float, # X-direction spacing (in units length)
    dely:float, # Y-direction spacing (in units length)
)->float: # Focal length (in units length)

Call self as a function.

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get_principal_point

def get_principal_point(
    intrinsic, # Intrinsic matrix (3 x 3 tensor)
    height:int, # Y-direction length (in units pixels)
    width:int, # X-direction length (in units pixels)
    delx:float, # X-direction spacing (in units length)
    dely:float, # Y-direction spacing (in units length)
):

Call self as a function.

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parse_intrinsic_matrix

def parse_intrinsic_matrix(
    intrinsic, # Intrinsic matrix (3 x 3 tensor)
    height:int, # Y-direction length (in units pixels)
    width:int, # X-direction length (in units pixels)
    delx:float, # X-direction spacing (in units length)
    dely:float, # Y-direction spacing (in units length)
):

Call self as a function.

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make_intrinsic_matrix

def make_intrinsic_matrix(
    detector:Detector
):

Call self as a function.