X-AnyLabeling系列：掩码转多边形坐标点

掩码转多边形坐标点

代码参考: X-AnyLabeling中的.\X-AnyLabeling\ tools\polygon_mask_conversion.py。这里主要拆分出掩码转成多边形坐标点存储在json文件的部分，同时增加了参数和支持带有中文名的路径。

代码示例

import os
import cv2
import json
import numpy as npdef get_image_size(image_file):image = cv2.imdecode(np.fromfile(image_file, dtype=np.uint8), 0)height, width = image.shape[:2]return width, heightdef reset(version):custom_data = dict(version=version,flags={},shapes=[],imagePath="",imageData=None,imageHeight=-1,imageWidth=-1,)return custom_datadef mask_to_polygon(img_file, mask_file, json_file,version,epsilon_factor=0.001, shape_dict=None,approx_len_threshold=5
):custom_data = reset(version)# binary_mask = cv2.imread(mask_file, cv2.IMREAD_GRAYSCALE)binary_mask = cv2.imdecode(np.fromfile(mask_file, dtype=np.uint8), 0)contours, _ = cv2.findContours(binary_mask, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)image_name = os.path.basename(img_file)for contour in contours:epsilon = epsilon_factor * cv2.arcLength(contour, True)approx = cv2.approxPolyDP(contour, epsilon, True)if len(approx) < approx_len_threshold:print(f"{image_name}: \contour too small, len={len(approx)}")continuefor point in approx:x, y = point[0].tolist()shape_dict["points"].append([x, y])custom_data["shapes"].append(shape_dict)image_width, image_height = get_image_size(img_file)custom_data["imagePath"] = image_namecustom_data["imageHeight"] = image_heightcustom_data["imageWidth"] = image_widthwith open(json_file, "w", encoding="utf-8") as f:json.dump(custom_data, f, indent=2, ensure_ascii=False)if __name__ == "__main__":image_path = "./images/test.jpg"mask_path = "./masks/test.png"json_path = "./jsons/test.json"shape_dict = {"label": "test","text": "test text","points": [],"group_id": None,"shape_type": "polygon","flags": {},}mask_to_polygon(image_path, mask_path, json_path, epsilon_factor=0.001,version="2.4.0",shape_dict=shape_dict,approx_len_threshold=5)