物体検出で被ったものを除外したい

物体検出で検出したものをディレクトリに保存
↓
同じ物体を検出（対象物を枠で囲ったときに２重してしまった場合）
↓
枠が被った値を計算し、規定値を上回ったらその画像は保存しない

[ここのブログ]を参考にしたのですが(https://qiita.com/neriai/items/e718290e8b14b0594008)

python
1# -*- coding: utf-8 -*-
2
3import cv2
4import matplotlib.pyplot as plt
5import matplotlib.patches as mpatches
6import selectivesearch
7import os
8
9
10def main():
11    # loading lena image
12    img = cv2.imread("sample.png")
13
14    # perform selective search
15    img_lbl, regions = selectivesearch.selective_search(
16        img,
17        scale=500,
18        sigma=0.9,
19        min_size=10
20    )
21
22    candidates = set()
23
24    for r in regions:
25        # excluding same rectangle (with different segments)
26        if r['rect'] in candidates:
27            continue
28
29        # excluding regions smaller than 2000 pixels
30        if r['size'] < 2000:
31            continue
32
33        # distorted rects
34        x, y, w, h = r['rect']
35
36        if w / h > 1.2 or h / w > 1.2:
37            continue
38
39        candidates.add(r['rect'])
40
41    # draw rectangles on the original image
42    fig, ax = plt.subplots(ncols=1, nrows=1, figsize=(6, 6))
43    ax.imshow(img)
44
45    overlaps = {}
46
47    # オーバーラップの数をカウントして配列に代入します。
48    for x, y, w, h in candidates:
49        group = '%s_%s_%s_%s' % (x, y, w, h)
50
51        for x2, y2, w2, h2 in candidates:
52            if x2 - w < x < x2 + w2 and y2 - h < y < y2 + h2:
53
54                if not group in overlaps:
55                    overlaps[group] = 0
56
57                overlaps[group] = overlaps[group] + 1
58
59    print overlaps
60
61    # オーバーラップの数が30以上のファイルを出力します（30は勝手に閾値を敷いています）。
62    for key, overlap in enumerate(overlaps):
63        if overlap > 30:
64            for x, y, w, h in candidates:
65                group = x + y + w + h
66
67                if group in overlaps:
68                    cv2.imwrite("{ディレクトリパス}" + str(group) + '.png', img[y:y + h, x:x + w])
69
70if __name__ == "__main__":
71    main()

このようなエラーが出ました

python
1
2---------------------------------------------------------------------------
3TypeError                                 Traceback (most recent call last)
4<ipython-input-95-91f2b2a72a36> in <module>
5     80 
6     81 if __name__ == "__main__":
7---> 82     main()
8
9<ipython-input-95-91f2b2a72a36> in main()
10     71     # オーバーラップの数が30以上のファイルを出力します（30は勝手に閾値を敷いています）。
11     72     for key, overlap in enumerate(overlaps):
12---> 73         if overlap > 30:
13     74             for x, y, w, h in candidates:
14     75                 group = x + y + w + h
15 '>' not supported between instances of 'str' and 'int'