ct_scan_geometry — TOMOGRAPHY ct_scan op

• Data kinds: कोई नहीं → ctgeometry (केवल arguments से तय होने वाला op — यह कोई image या data input नहीं लेता)

• Call: import fullseye as fs; fs.ledger.ct_scan_geometry(scan='cone', n_views=360, n_u=256, n_v=256, vol_shape=(256, 256, 256), voxel=1.0, du=None, dv=None, dso=None, dsd=None, detector='flat', arc_deg=None, start_deg=0.0, angles_deg=None, offset_u=0.0, pitch=1.0, turns=None, tilt_deg=30.0) (implementation को सीधे call करना हो तो import ctscan; ctscan.ct_scan_geometry(scan='cone', n_views=360, n_u=256, n_v=256, vol_shape=(256, 256, 256), voxel=1.0, du=None, dv=None, dso=None, dsd=None, detector='flat', arc_deg=None, start_deg=0.0, angles_deg=None, offset_u=0.0, pitch=1.0, turns=None, tilt_deg=30.0), registry से लेना हो तो opstomography.get("ct_scan_geometry"))

• GPU: नहीं (केवल CPU reference implementation)

उपयोग

एक CT स्कैन का वर्णन: हर व्यू में स्रोत और डिटेक्टर कहाँ हैं।

> नीचे का विस्तृत विवरण मूल text में है — सारांश और headings का अनुवाद हो चुका है।

Every other operator in this family reads this dict and nothing else, so a new scan is a new orbit here and never a new projector. The result carries, for each view, source (for a parallel beam the ray direction), det_center, det_u and det_v in physical units with the origin at the volume centre.

The orbits. "cone" is a circle around the z axis with a flat panel, the industrial default; "fan" the same with a single detector row, for a single slice; "helical" the cone with the source and detector moving along z, pitch detector heights per turn; "laminography" a circle tilted so that the beam meets the board normal at tilt_deg (90 is an ordinary CT, and dso=None with scan="laminography" is the parallel-beam form); "tomosynthesis" a source arc of arc_deg over a detector that does not move; "parallel" parallel rays.

A short scan is arc_deg < 360, a few-view scan a small n_views, a limited-angle scan a small arc_deg or an explicit angles_deg, and an offset detector offset_u bins. Those are parameters of the orbit, not new scans.

:param scan: one of SCANS. :param n_views: views, 1 .. 65536; ignored when *angles_deg* is given. :param n_u: detector columns. :param n_v: detector rows. :param vol_shape: (Z, Y, X) of the reconstruction, or one int for a cube. :param voxel: voxel edge in physical units. :param du: detector column pitch; None gives one voxel at the isocentre. :param dv: detector row pitch; None gives one voxel at the isocentre. :param dso: source to isocentre distance; None gives 3 volume widths. :param dsd: source to detector distance; None gives 2 * dso. :param detector: one of DETECTORS. :param arc_deg: orbit length; None gives 360, or 180 for "parallel", or 40

for "tomosynthesis".

:param start_deg: first view angle. :param angles_deg: explicit increasing view angles; overrides *n_views* and *arc_deg*. :param offset_u: detector shift in bins along u, for an extended field of view. :param pitch: helical table feed per turn, in detector heights at the isocentre. :param turns: helical turns; None covers the volume height. :param tilt_deg: laminography angle between the beam and the rotation axis. :returns: geometry dict; vol_shape, n_views, n_v, n_u and the per-view

arrays are the public fields.

:raises ValueError: on an unknown scan or detector, a non-positive length, a source

inside the volume, arc above 360, or an oversized request.

संदर्भ (sample data, साहित्य)

• Sample data catalog (DL URL / license) — 2-D के लिए skimage.data (BSD/public) + synthetic, 3-D के लिए real data sources (Stanford/PDS आदि) के DL URL।

• Operators का स्रोत और संदर्भ — इस op family के मूल research/methods के स्रोत।

• Algorithm का मानक स्रोत (लेखक, वर्ष) और उपयोग ऊपर की family usage guide में दिए गए हैं।

चलाए जा सकने वाले उदाहरण (verified samples जो सच में यह op call करते हैं)

• ct_scan_modes — py -3.11 examples/ct_scan_modes.py

वे अगले ops जिनसे type जुड़ता है (ctgeometry को input के रूप में लेते हैं)

ellipsoid_projections · ct_forward_project · ct_adjoint_project · fdk_reconstruct · sirt_reconstruct · os_sart_reconstruct · tv_reconstruct · ct_dual_energy_reconstruct

इसी category के (ct_scan)

shepp_logan_3d · ellipsoid_phantom · ellipsoid_projections · ct_forward_project · ct_adjoint_project · fdk_reconstruct · sirt_reconstruct · os_sart_reconstruct


*Provenance: ctscan.py — TOMOGRAPHY operator registry. यह per-op note tools/opdocs.py md से अपने-आप generate होता है (हाथ से edit न करें)।*

© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.