nx_eye_detect.nx

nx_eye_detect.nx -- iris/eye-pair detection wrapping nx_geom_hough_circle_r. This is the KEYSTONE primitive. Once eye_width_px is measured, every other anatomical axis is a Q10 ratio from it via nx_canon_proportions. Pipeline: 1. Caller crops to face bbox (already from nx_region_segment). 2. Caller computes sobel_x + sobel_y + edge mask. 3. nx_eye_detect_iris_pair() sweeps candidate iris radii, collects circles, pairs the best two within upper-half of face. 4. Output: flat-array result (no struct pointer return -> avoids nxc2 codegen bug). Result layout (i64): result[0] = eye_count (0, 1, or 2) result[1] = eye_width_px (palpebral fissure ≈ 5 * iris_radius) result[2] = iris_radius_px (the raw Hough measurement) result[3] = left_eye_cx (in face-bbox coords) result[4] = left_eye_cy result[5] = left_eye_iris_r result[6] = right_eye_cx result[7] = right_eye_cy result[8] = right_eye_iris_r result[9] = pair_quality_q10 (1024 = perfect horizontal alignment + matched radius) Constants: - iris radius range tries 3..16 px (typical iris in face crop) - palpebral fissure ≈ 5 × iris_radius_px (Loomis canon: eye width = unit) nx_safety_envelope: intended_use: "Eye detection / iris localization -- input primitive for the anatomy-as-proportions substrate per cardinal feedback-eye-as- keystone-anatomy-as-proportions" sil_target: SIL1 asil_target: QM dal_target: NONE evidence: [Loomis_anatomy_canon_basis, integer_pixel_arithmetic, sealed_verdict_enum]