| """ | |
| Functions to compute distance ratios between specific pairs of facial landmarks | |
| """ | |
| import numpy as np | |
| def calculate_distance_ratio(lmk: np.ndarray, idx1: int, idx2: int, idx3: int, idx4: int, eps: float = 1e-6) -> np.ndarray: | |
| """ | |
| Calculate the ratio of the distance between two pairs of landmarks. | |
| Parameters: | |
| lmk (np.ndarray): Landmarks array of shape (B, N, 2). | |
| idx1, idx2, idx3, idx4 (int): Indices of the landmarks. | |
| eps (float): Small value to avoid division by zero. | |
| Returns: | |
| np.ndarray: Calculated distance ratio. | |
| """ | |
| return (np.linalg.norm(lmk[:, idx1] - lmk[:, idx2], axis=1, keepdims=True) / | |
| (np.linalg.norm(lmk[:, idx3] - lmk[:, idx4], axis=1, keepdims=True) + eps)) | |
| def calc_eye_close_ratio(lmk: np.ndarray, target_eye_ratio: np.ndarray = None) -> np.ndarray: | |
| """ | |
| Calculate the eye-close ratio for left and right eyes. | |
| Parameters: | |
| lmk (np.ndarray): Landmarks array of shape (B, N, 2). | |
| target_eye_ratio (np.ndarray, optional): Additional target eye ratio array to include. | |
| Returns: | |
| np.ndarray: Concatenated eye-close ratios. | |
| """ | |
| lefteye_close_ratio = calculate_distance_ratio(lmk, 6, 18, 0, 12) | |
| righteye_close_ratio = calculate_distance_ratio(lmk, 30, 42, 24, 36) | |
| if target_eye_ratio is not None: | |
| return np.concatenate([lefteye_close_ratio, righteye_close_ratio, target_eye_ratio], axis=1) | |
| else: | |
| return np.concatenate([lefteye_close_ratio, righteye_close_ratio], axis=1) | |
| def calc_lip_close_ratio(lmk: np.ndarray) -> np.ndarray: | |
| """ | |
| Calculate the lip-close ratio. | |
| Parameters: | |
| lmk (np.ndarray): Landmarks array of shape (B, N, 2). | |
| Returns: | |
| np.ndarray: Calculated lip-close ratio. | |
| """ | |
| return calculate_distance_ratio(lmk, 90, 102, 48, 66) | |