feature op• Data kinds: voxel → measurement
• Call: import fullseye as fs; fs.ledger.vol_euler_number(vol_binary, connectivity=26) (implementation को सीधे call करना हो तो import volops; volops.vol_euler_number(vol_binary, connectivity=26), registry से लेना हो तो ops3d.get("vol_euler_number"))
• Ledger के ज़रिए return value: fullseye.ledger.vol_euler_number(...) केवल घोषित out type measurement का value लौटाता है (मूल function सहायक जानकारी भी लौटाता है)। जो हिस्सा छोड़ दिया गया है उसकी ज़रूरत हो तो fullseye.ledger.vol_euler_number.raw(...) का उपयोग करें, या volops.vol_euler_number को सीधे call करें।
• मूल function का return: chi(b0-b1+b2)
binary volume की Euler characteristic, उसके तीन Betti numbers में बाँटी गई।
> नीचे का विस्तृत विवरण मूल text में है — सारांश और headings का अनुवाद हो चुका है।
chi = b0 - b1 + b2 where b0 counts separate objects, b1 counts tunnels (handles that pass right through) and b2 counts enclosed cavities. For porous media that split is the whole point:
b1 is open, connected porosity — the paths a fluid can take — while b2 is closed porosity that no fluid reaches. A single chi cannot tell a foam with many tunnels from one with many sealed bubbles; the three numbers can.
*connectivity* is 6, 18 or 26 for the foreground; the background is counted with the complementary neighbourhood (26 vs 6), which is what makes the pair of counts consistent — using the same neighbourhood for both is the classical way to produce a set that is simultaneously connected and disconnected.
Returns {"euler": chi, "objects": b0, "tunnels": b1, "cavities": b2, "connectivity": connectivity}. b1 is derived as b0 + b2 - chi, so it inherits the exactness of the other three.
HALCON's euler_number is 2-D (regions) only; there is no voxel equivalent.
• 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।
• ct_porosity_and_fibre_morphometry — py -3.11 examples_3d/ct_porosity_and_fibre_morphometry.py
measurement को input के रूप में लेते हैं)vol_gaussian_psf · fuse_to_voxel · fresnel_reflectance · snell_angle
feature)sobel3d · hessian3d · curvature_maps · edt_jfa · edt_jfa_vector · vol_frangi · vol_local_std · vol_local_thickness
*Provenance: volops.py — 3D 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.