geometry op• 데이터 종류: sinogram → sinogram
• 호출: import tomography; tomography.sinogram_center_shift(sinogram, shift_px=None, angles_deg=None)(또는 opstomography.get("sinogram_center_shift"))
사이노그램을 회전축에 맞춰 다시 중심화합니다.
> 아래 상세 설명은 원문입니다 —— 요약과 제목은 번역되어 있습니다.
Shifts every projection by `-shift_px` along the detector axis with linear
interpolation. With `shift_px=None` the shift is measured first by
:func:sinogram_center_of_rotation, which makes this the one-call fix.
Round-trip on the Shepp-Logan phantom, shifting by *d* and back:
d max |error| relative to the peak line integral
1.00 px 0.0e+00 0.0e+00 (an integer shift is exact)
0.50 px 1.4e-01 1.2e-01
0.25 px 1.1e-01 9.2e-02
A *fractional* shift is not a small operation and this is the operator's
honest limitation: 12 % of the peak, on a phantom with sharp edges, from one
round trip. Interpolation is a low-pass filter and the sinogram of an edge is
not band-limited, so there is nothing to recover on the way back. Using a
Fourier shift instead would trade this visible blur for invisible ringing at
the detector edges, which is worse in the way that matters here. The
consequence is in :func:sinogram_center_of_rotation's table: an integer
centre error is fully repairable, a half-pixel one is not.
:param sinogram: `(n_angles, n_detectors)`.
:param shift_px: axis offset in detector bins; `None` -> measure it.
:param angles_deg: view angles, used only when *shift_px* is `None`.
:returns: `(n_angles, n_detectors)` float64 sinogram.
:raises ValueError: if `|shift_px|` is at or past half the detector width —
past that the object has been shifted out of the field of view and what
comes back is edge padding, which reconstructs as a plausible, empty slice.
• 샘플 데이터 카탈로그(DL URL / 라이선스) —— 2-D 는 skimage.data(BSD/public)+ 합성, 3-D 는 실데이터 소스(Stanford/PDS 등)의 DL URL.
• 연산자의 내력·참고문헌 —— 이 연산자 족의 바탕이 된 연구/기법의 출처.
• 알고리즘의 정전(저자·연도)과 용도는 위의 패밀리 사용 가이드에 적혀 있습니다.
• ct_reconstruction — py -3.11 examples/ct_reconstruction.py
sinogram 를 입력으로 받는 것)backproject_sinogram · filtered_backprojection · sart_reconstruct · beam_hardening_apply · beam_hardening_correct · ring_artifact_apply · ring_artifact_remove · metal_trace_interpolate
geometry)*Provenance: tomography.py — TOMOGRAPHY 연산자 레지스트리. 이 op 노트는 tools/opdocs.py md 가 자동 생성합니다(직접 편집하지 마세요).*
© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.