Python合并重叠矩形框

import cv2
import numpy as np


def checkOverlap(boxa, boxb):
    x1, y1, w1, h1 = boxa
    x2, y2, w2, h2 = boxb
    if (x1 > x2 + w2):
        return 0
    if (y1 > y2 + h2):
        return 0
    if (x1 + w1 < x2):
        return 0
    if (y1 + h1 < y2):
        return 0
    colInt = abs(min(x1 + w1, x2 + w2) - max(x1, x2))
    rowInt = abs(min(y1 + h1, y2 + h2) - max(y1, y2))
    overlap_area = colInt * rowInt
    area1 = w1 * h1
    area2 = w2 * h2
    return overlap_area / (area1 + area2 - overlap_area)

def unionBox(a, b):
    x = min(a[0], b[0])
    y = min(a[1], b[1])
    w = max(a[0] + a[2], b[0] + b[2]) - x
    h = max(a[1] + a[3], b[1] + b[3]) - y
    return [x, y, w, h]

def intersectionBox(a, b):
    x = max(a[0], b[0])
    y = max(a[1], b[1])
    w = min(a[0] + a[2], b[0] + b[2]) - x
    h = min(a[1] + a[3], b[1] + b[3]) - y
    if w < 0 or h < 0:
        return ()
    return [x, y, w, h]

def rectMerge_sxf(rects: []):
    '''
    当通过connectedComponentsWithStats找到rects坐标时，
    注意前2個坐标是表示整個圖的，需要去除，不然就只有一個大框，
    在执行此函数前，可执行类似下面的操作。
    rectList = sorted(rectList)[2:]
    '''
    # rects => [[x1, y1, w1, h1], [x2, y2, w2, h2], ...]
    rectList = rects.copy()
    rectList.sort()
    new_array = []
    complete = 1
    # 要用while，不能forEach，因爲rectList內容會變
    i = 0
    while i < len(rectList):
        # 選後面的即可，前面的已經判斷過了，不需要重復操作
        j = i + 1
        succees_once = 0
        while j < len(rectList):
            boxa = rectList[i]
            boxb = rectList[j]
            # 判斷是否有重疊，注意只針對水平＋垂直情況，有角度旋轉的不行
            if checkOverlap(boxa, boxb):  # intersectionBox(boxa, boxb)
                complete = 0
                # 將合並後的矩陣加入候選區
                new_array.append(unionBox(boxa, boxb))
                succees_once = 1
                # 從原列表中刪除，因爲這兩個已經合並了，不刪除會導致重復計算
                rectList.remove(boxa)
                rectList.remove(boxb)
                break
            j += 1
        if succees_once:
            # 成功合並了一次，此時i不需要+1，因爲上面進行了remove(boxb)操作
            continue
        i += 1
    # 剩餘項是不重疊的，直接加進來即可
    new_array.extend(rectList)

    # 0: 可能還有未合並的，遞歸調用;
    # 1: 本次沒有合並項，說明全部是分開的，可以結束退出
    if complete == 0:
        complete, new_array = rectMerge_sxf(new_array)
    return complete, new_array


box = [[20, 20, 20, 20], [100, 100, 100, 100], [60, 60, 50, 50], [50, 50, 50, 50]]
_, res = rectMerge_sxf(box)
print(res)
print(box)

img = np.ones([256, 256, 3], np.uint8)
for x,y,w,h in box:
    img = cv2.rectangle(img, (x,y), (x+w,y+h), (0, 255, 0), 2)
cv2.imshow('origin', img)

img = np.ones([256, 256, 3], np.uint8)
for x,y,w,h in res:
    img = cv2.rectangle(img, (x,y), (x+w,y+h), (0, 0, 255), 2)
cv2.imshow('after', img)

cv2.waitKey(0)