OpenCV HoughCircles未检测到图像中的所有圆圈

Question

我有这张图片：

而且，我想检测其中的所有圆圈，我正在使用this教程。

这是代码：

import argparse
import cv2 as cv
import numpy as np
# construct the argument parser and parse the arguments
ap = argparse.ArgumentParser()
ap.add_argument("-i", "--image", required = True, help = "Path to the image")
args = vars(ap.parse_args())
# load the image, clone it for output, and then convert it to grayscale
image = cv.imread(args["image"])

output = image.copy()
gray = cv.cvtColor(image, cv.COLOR_BGR2GRAY)
# detect circles in the image
circles = cv.HoughCircles(gray,cv.HOUGH_GRADIENT, 1.2, 75)

# ensure at least some circles were found
if circles is not None:
    # convert the (x, y) coordinates and radius of the circles to integers
    circles = np.round(circles[0, :]).astype("int")
    # loop over the (x, y) coordinates and radius of the circles
    for (x, y, r) in circles:
        # draw the circle in the output image, then draw a rectangle
        # corresponding to the center of the circle
        cv.circle(output, (x, y), r, (0, 255, 0), 4)
        cv.rectangle(output, (x - 5, y - 5), (x + 5, y + 5), (0, 128, 255), -1)

    cv.imshow("output", np.hstack([image, output]))
    cv.waitKey(0)

这是运行代码后的输出图像：

结果很奇怪，为什么会这样呢？ 如何检测其中的所有圈子？我应该更改哪些参数来实现它？

使用后：

circles = cv.HoughCircles(gray,cv.HOUGH_GRADIENT, 1.5, 75)

我知道了：  

Answer 1

cv.imshow("output", np.hstack([image, output]))由于此代码。您正在通过np.hstack.堆叠原始图像和输出图像

仅打印cv.imshow("output",output).