from pathlib import Path

import cv2 as cv
import numpy as np


IMAGE_DIR = Path("calibration")
OUTPUT_PATH = Path("calibration.npz")
PATTERN_SIZE = (7, 6)
SQUARE_SIZE = 25.0
MIN_FRAMES = 10

image_paths = sorted(
    path
    for path in IMAGE_DIR.iterdir()
    if path.suffix.lower() in {".jpg", ".jpeg", ".png", ".tif", ".tiff"}
)
if not image_paths:
    raise SystemExit(f"no calibration images found in {IMAGE_DIR}")

columns, rows = PATTERN_SIZE
object_template = np.zeros((rows * columns, 3), np.float32)
object_template[:, :2] = np.mgrid[0:columns, 0:rows].T.reshape(-1, 2)
object_template *= SQUARE_SIZE