| |
| import os |
| import json |
| import numpy as np |
| from pathlib import Path |
|
|
| def load_camera_params(params_file): |
| """ |
| Load camera parameters from a JSON file. |
| |
| Args: |
| params_file (str): Path to the JSON file containing camera parameters |
| |
| Returns: |
| dict: Dictionary containing camera parameters |
| """ |
| if not os.path.exists(params_file): |
| print(f"Warning: Camera parameters file {params_file} not found. Using default parameters.") |
| return None |
| |
| try: |
| with open(params_file, 'r') as f: |
| params = json.load(f) |
| |
| |
| params['camera_matrix'] = np.array(params['camera_matrix']) |
| params['dist_coeffs'] = np.array(params['dist_coeffs']) |
| params['projection_matrix'] = np.array(params['projection_matrix']) |
| |
| print(f"Loaded camera parameters from {params_file}") |
| print(f"Camera matrix:\n{params['camera_matrix']}") |
| print(f"Projection matrix:\n{params['projection_matrix']}") |
| |
| return params |
| |
| except Exception as e: |
| print(f"Error loading camera parameters: {e}") |
| return None |
|
|
| def create_projection_matrix(camera_matrix, R=None, t=None): |
| """ |
| Create a projection matrix from camera intrinsic and extrinsic parameters. |
| |
| Args: |
| camera_matrix (numpy.ndarray): Camera intrinsic matrix (3x3) |
| R (numpy.ndarray): Rotation matrix (3x3) |
| t (numpy.ndarray): Translation vector (3x1) |
| |
| Returns: |
| numpy.ndarray: Projection matrix (3x4) |
| """ |
| if R is None: |
| R = np.eye(3) |
| |
| if t is None: |
| t = np.zeros((3, 1)) |
| |
| |
| RT = np.hstack((R, t)) |
| |
| |
| projection_matrix = camera_matrix @ RT |
| |
| return projection_matrix |
|
|
| def apply_camera_params_to_estimator(bbox3d_estimator, params): |
| """ |
| Apply camera parameters to a 3D bounding box estimator. |
| |
| Args: |
| bbox3d_estimator: BBox3DEstimator instance |
| params (dict): Dictionary containing camera parameters |
| |
| Returns: |
| bbox3d_estimator: Updated BBox3DEstimator instance |
| """ |
| if params is None: |
| print("Warning: No camera parameters provided. Using default parameters.") |
| return bbox3d_estimator |
| |
| |
| if 'camera_matrix' in params: |
| bbox3d_estimator.K = params['camera_matrix'] |
| |
| |
| if 'projection_matrix' in params: |
| bbox3d_estimator.P = params['projection_matrix'] |
| |
| print("Applied camera parameters to 3D bounding box estimator") |
| |
| return bbox3d_estimator |
|
|
| def main(): |
| """Example usage of the camera parameter functions.""" |
| |
| |
| |
| |
| params_file = "camera_params.json" |
| |
| |
| camera_height = 1.65 |
| |
| |
| |
| params = load_camera_params(params_file) |
| |
| if params: |
| print("\nCamera Parameters:") |
| print(f"Image dimensions: {params['image_width']}x{params['image_height']}") |
| print(f"Reprojection error: {params['reprojection_error']}") |
| |
| |
| print(f"\nExample: Creating a projection matrix with camera raised {camera_height}m above ground") |
| R = np.eye(3) |
| t = np.array([[0], [camera_height], [0]]) |
| |
| projection_matrix = create_projection_matrix(params['camera_matrix'], R, t) |
| print(f"New projection matrix:\n{projection_matrix}") |
|
|
| if __name__ == "__main__": |
| main() |
