pyr0ball
0dcc25164d
- BlinkDetector: EAR-based blink detection (left/right/both), 6 tests - GazeEstimator: iris-to-eye-corner ratio gaze direction, frozen GazeDirection dataclass, 4 tests - HeadPoseEstimator: velocity-based nod/shake/tilt detection (stateful, no tests — daemon smoke test) - HandGestureDetector: normalize_hand + tip-distance open/pinch/fist classifier (no tests — daemon smoke test) - TDD: blink and gaze followed RED→GREEN cycle; Black applied to all 6 files
62 lines
1.8 KiB
Python
62 lines
1.8 KiB
Python
"""
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Blink detection from MediaPipe Face Mesh landmarks.
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Uses the Eye Aspect Ratio (EAR) method: when the eye closes, the vertical
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landmark distances shrink relative to the horizontal width, driving EAR toward 0.
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"""
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from __future__ import annotations
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from enum import Enum
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from typing import Optional
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import numpy as np
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_LEFT_EYE = [33, 160, 158, 133, 153, 144]
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_RIGHT_EYE = [362, 385, 387, 263, 373, 380]
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class BlinkEvent(str, Enum):
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LEFT = "left_blink"
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RIGHT = "right_blink"
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BOTH = "both_blink"
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def eye_aspect_ratio(landmarks: np.ndarray, indices: list[int]) -> float:
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"""
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EAR = (||p2-p6|| + ||p3-p5||) / (2 * ||p1-p4||)
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~0.3 for open eye, ~0.0 for closed.
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"""
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p1, p2, p3, p4, p5, p6 = [landmarks[i] for i in indices]
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vert_a = np.linalg.norm(p2 - p6)
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vert_b = np.linalg.norm(p3 - p5)
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horiz = np.linalg.norm(p1 - p4)
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if horiz < 1e-6:
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return 0.0
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return float((vert_a + vert_b) / (2.0 * horiz))
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class BlinkDetector:
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"""Detect left, right, or both-eye blinks from face mesh landmarks."""
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def __init__(self, threshold: float = 0.20) -> None:
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self._threshold = threshold
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def detect(self, face_landmarks: np.ndarray) -> Optional[BlinkEvent]:
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"""
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Args:
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face_landmarks: (478, 3) float32 — MediaPipe Face Mesh with iris refinement.
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Returns:
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BlinkEvent if a blink is detected, else None.
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"""
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left_closed = eye_aspect_ratio(face_landmarks, _LEFT_EYE) < self._threshold
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right_closed = eye_aspect_ratio(face_landmarks, _RIGHT_EYE) < self._threshold
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if left_closed and right_closed:
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return BlinkEvent.BOTH
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if left_closed:
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return BlinkEvent.LEFT
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if right_closed:
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return BlinkEvent.RIGHT
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return None
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