import json
import cv2
import os
from pathlib import Path

# ==================== 你只需要改这 1 个路径 ====================
LABEL_FOLDER = "篆文pic"  # 放 json 和原图的文件夹（必须同目录）
OUTPUT_FOLDER = "chars"   # 切割后输出的文件夹
# ===============================================================

Path(OUTPUT_FOLDER).mkdir(exist_ok=True)

def imread_unicode(path):
    return cv2.imdecode(np.fromfile(path, dtype=np.uint8), cv2.IMREAD_COLOR)

def imwrite_unicode(path, img):
    cv2.imencode('.png', img)[1].tofile(path)

def cut_labels(json_path):
    # 读取标注
    with open(json_path, 'r', encoding='utf-8') as f:
        data = json.load(f)

    # 原图路径
    img_path = os.path.join(os.path.dirname(json_path), data['imagePath'])
    img = imread_unicode(img_path)
    if img is None:
        print(f"找不到图片：{img_path}")
        return

    # 文件名前缀
    prefix = Path(data['imagePath']).stem

    # 遍历每个框
    idx = 0
    for shape in data['shapes']:
        points = shape['points']
        label = shape['label']

        # 坐标转整数
        x1 = int(min(p[0] for p in points))
        y1 = int(min(p[1] for p in points))
        x2 = int(max(p[0] for p in points))
        y2 = int(max(p[1] for p in points))

        # 切割
        crop = img[y1:y2, x1:x2]

        # 保存
        save_name = f"{prefix}_{label}_{idx:02d}.png"
        save_path = os.path.join(OUTPUT_FOLDER, save_name)
        imwrite_unicode(save_path, crop)
        idx += 1

    print(f"✅ 已切割：{img_path} → {idx} 个字")

if __name__ == "__main__":
    import numpy as np
    json_files = list(Path(LABEL_FOLDER).glob("*.json"))
    for jf in json_files:
        cut_labels(jf)

    print("\n🎉 全部切割完成！输出在：", OUTPUT_FOLDER)