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Documentation Index

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Public camera intrinsics types and convenience constructors.

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SimpleIntrinsics Objects

@dataclass
class SimpleIntrinsics()
Simple camera intrinsics (focal length + principal point). Prefer the dedicated constructors (intrinsics_pinhole(), intrinsics_radial(), intrinsics_plumb_bob(), intrinsics_fisheye()) or the generic intrinsics_simple() rather than instantiating this class directly. The extra dict holds distortion coefficients and optional fields. Distortion coefficients are model-specific. The following optional fields apply to all models: dfx, dfy, dox, doy, skew.

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AdvancedIntrinsics Objects

@dataclass
class AdvancedIntrinsics()
Advanced camera intrinsics (full calibration matrices). .. warning:: In most cases SimpleIntrinsics (via intrinsics_simple() or one of the dedicated constructors) is sufficient and much easier to work with. Only use advanced intrinsics when you have pre-computed full K / R / P calibration matrices and genuinely need to supply them directly. Prefer intrinsics_advanced() rather than instantiating this class directly. Arguments:
  • k - 9-element intrinsic camera matrix (row-major 3x3). Validated to have exactly 9 elements at build time.
  • r - 9-element rectification matrix (row-major 3x3). Validated to have exactly 9 elements at build time.
  • p - 12-element projection matrix (row-major 3x4). Validated to have exactly 12 elements at build time.
  • model - Optional distortion model name.

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intrinsics_simple

def intrinsics_simple(fx: float,
                      fy: float,
                      ox: float,
                      oy: float,
                      *,
                      model: str | None = None,
                      **kwargs: float) -> SimpleIntrinsics
Build simple camera intrinsics (focal length + principal point). For models without a dedicated constructor, pass the model name and its coefficients as keyword arguments:: intrinsics_simple(fx, fy, ox, oy, model=“division”, k=0.01) intrinsics_simple(fx, fy, ox, oy, model=“ucm”, xi=0.5, k1=0.1, k2=0.0, k3=0.0) Arguments:
  • fx - Focal length along the x-axis (pixels).
  • fy - Focal length along the y-axis (pixels).
  • ox - Principal-point x offset (pixels).
  • oy - Principal-point y offset (pixels).
  • model - Optional distortion model name.
  • **kwargs - Distortion coefficients and optional extra fields.

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intrinsics_advanced

def intrinsics_advanced(k: Sequence[float] | None = None,
                        r: Sequence[float] | None = None,
                        p: Sequence[float] | None = None,
                        *,
                        model: str | None = None) -> AdvancedIntrinsics
Build advanced camera intrinsics using full calibration matrices. .. warning:: In most cases intrinsics_simple() (or one of the dedicated constructors) is sufficient. Only reach for advanced intrinsics when you have pre-computed K / R / P matrices. Arguments:
  • k - 9-element intrinsic camera matrix (row-major 3x3).
  • r - 9-element rectification matrix (row-major 3x3).
  • p - 12-element projection matrix (row-major 3x4).
  • model - Optional distortion model name.

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intrinsics_pinhole

def intrinsics_pinhole(fx: float, fy: float, ox: float,
                       oy: float) -> SimpleIntrinsics
Build pinhole intrinsics (no distortion coefficients). Arguments:
  • fx - Focal length along the x-axis (pixels).
  • fy - Focal length along the y-axis (pixels).
  • ox - Principal-point x offset (pixels).
  • oy - Principal-point y offset (pixels).

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intrinsics_radial

def intrinsics_radial(fx: float, fy: float, ox: float, oy: float, *, k1: float,
                      k2: float, k3: float) -> SimpleIntrinsics
Build intrinsics with a radial distortion model. Arguments:
  • fx - Focal length along the x-axis (pixels).
  • fy - Focal length along the y-axis (pixels).
  • ox - Principal-point x offset (pixels).
  • oy - Principal-point y offset (pixels).
  • k1 - First radial distortion coefficient.
  • k2 - Second radial distortion coefficient.
  • k3 - Third radial distortion coefficient.

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intrinsics_plumb_bob

def intrinsics_plumb_bob(fx: float, fy: float, ox: float, oy: float, *,
                         k1: float, k2: float, k3: float, t1: float,
                         t2: float) -> SimpleIntrinsics
Build intrinsics with a plumb-bob (Brown-Conrady) distortion model. Arguments:
  • fx - Focal length along the x-axis (pixels).
  • fy - Focal length along the y-axis (pixels).
  • ox - Principal-point x offset (pixels).
  • oy - Principal-point y offset (pixels).
  • k1 - First radial distortion coefficient.
  • k2 - Second radial distortion coefficient.
  • k3 - Third radial distortion coefficient.
  • t1 - First tangential distortion coefficient.
  • t2 - Second tangential distortion coefficient.

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intrinsics_fisheye

def intrinsics_fisheye(fx: float, fy: float, ox: float, oy: float, *,
                       k1: float, k2: float, k3: float,
                       k4: float) -> SimpleIntrinsics
Build intrinsics with a fisheye (Kannala-Brandt) distortion model. Arguments:
  • fx - Focal length along the x-axis (pixels).
  • fy - Focal length along the y-axis (pixels).
  • ox - Principal-point x offset (pixels).
  • oy - Principal-point y offset (pixels).
  • k1 - First distortion coefficient.
  • k2 - Second distortion coefficient.
  • k3 - Third distortion coefficient.
  • k4 - Fourth distortion coefficient.

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intrinsics_rational_polynomial

def intrinsics_rational_polynomial(fx: float, fy: float, ox: float, oy: float,
                                   *, k1: float, k2: float, k3: float,
                                   k4: float, k5: float, k6: float, t1: float,
                                   t2: float) -> SimpleIntrinsics
Build intrinsics with a rational-polynomial distortion model. Arguments:
  • fx - Focal length along the x-axis (pixels).
  • fy - Focal length along the y-axis (pixels).
  • ox - Principal-point x offset (pixels).
  • oy - Principal-point y offset (pixels).
  • k1 - First radial distortion coefficient.
  • k2 - Second radial distortion coefficient.
  • k3 - Third radial distortion coefficient.
  • k4 - Fourth radial distortion coefficient.
  • k5 - Fifth radial distortion coefficient.
  • k6 - Sixth radial distortion coefficient.
  • t1 - First tangential distortion coefficient.
  • t2 - Second tangential distortion coefficient.

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intrinsics_cylindrical

def intrinsics_cylindrical(fx: float, fy: float, ox: float,
                           oy: float) -> SimpleIntrinsics
Build intrinsics with a cylindrical distortion model (no coefficients). Arguments:
  • fx - Focal length along the x-axis (pixels).
  • fy - Focal length along the y-axis (pixels).
  • ox - Principal-point x offset (pixels).
  • oy - Principal-point y offset (pixels).