問題描述
我正在嘗試檢測黑/白點目標的中心，如圖所示.我嘗試使用 cv2.HoughCircles 方法，但 1，只能檢測 2 到 3 個目標，2，當我將找到的圓圈重新繪制到圖像上時，它們總是略微偏移.
I'm trying to detect the center of black/white dot targets, like in this picture. I've tried to use the cv2.HoughCircles method but 1, am only able to detect 2 to 3 targets, and 2, when I plot the found circles back onto the image, they're always offset slightly.
我是否使用了錯誤的方法?我應該使用 findContours 還是完全不同的東西?
Am I using the wrong method? Should I be using the findContours or something completely different?
這是我的代碼:
import cv2
from cv2 import cv
import os
import numpy as np
def showme(pic):
cv2.imshow('window',pic)
cv2.waitKey()
cv2.destroyAllWindows()
im=cv2.imread('small_test.jpg')
gray=cv2.cvtColor(im,cv2.COLOR_BGR2GRAY)
#I've tried blur,bw,tr... all give me poor results.
blur = cv2.GaussianBlur(gray,(3,3),0)
n,bw = cv2.threshold(blur,120,255,cv2.THRESH_BINARY)
tr=cv2.adaptiveThreshold(blur,255,0,1,11,2)
circles = cv2.HoughCircles(gray, cv.CV_HOUGH_GRADIENT, 3, 100, None, 200, 100, 5, 16)
try:
n = np.shape(circles)
circles=np.reshape(circles,(n[1],n[2]))
print circles
for circle in circles:
cv2.circle(im,(circle[0],circle[1]),circle[2],(0,0,255))
showme(im)
except:
print "no cicles found"
這是我當前的輸出:
推薦答案
播放我在另一篇文章中寫的代碼，我能夠取得稍微好一點的結果:
Playing the code I wrote in another post, I was able to achieve a slightly better result:
一切都與參數有關.始終如此.
您應該嘗試在此程序中調用 3 個重要的函數:cvSmooth()、cvCanny() 和 cvHoughCircles().他們每個人都有可能徹底改變結果.
There are 3 important functions that are called in this program that you should experiment with: cvSmooth(), cvCanny(), and cvHoughCircles(). Each of them has the potential to change the result drastically.
這里是 C 代碼:
IplImage* img = NULL;
if ((img = cvLoadImage(argv[1]))== 0)
{
printf("cvLoadImage failed
");
}
IplImage* gray = cvCreateImage(cvGetSize(img), IPL_DEPTH_8U, 1);
CvMemStorage* storage = cvCreateMemStorage(0);
cvCvtColor(img, gray, CV_BGR2GRAY);
// This is done so as to prevent a lot of false circles from being detected
cvSmooth(gray, gray, CV_GAUSSIAN, 7, 9);
IplImage* canny = cvCreateImage(cvGetSize(img),IPL_DEPTH_8U,1);
IplImage* rgbcanny = cvCreateImage(cvGetSize(img),IPL_DEPTH_8U,3);
cvCanny(gray, canny, 40, 240, 3);
CvSeq* circles = cvHoughCircles(gray, storage, CV_HOUGH_GRADIENT, 2, gray->height/8, 120, 10, 2, 25);
cvCvtColor(canny, rgbcanny, CV_GRAY2BGR);
for (size_t i = 0; i < circles->total; i++)
{
// round the floats to an int
float* p = (float*)cvGetSeqElem(circles, i);
cv::Point center(cvRound(p[0]), cvRound(p[1]));
int radius = cvRound(p[2]);
// draw the circle center
cvCircle(rgbcanny, center, 3, CV_RGB(0,255,0), -1, 8, 0 );
// draw the circle outline
cvCircle(rgbcanny, center, radius+1, CV_RGB(0,0,255), 2, 8, 0 );
printf("x: %d y: %d r: %d
",center.x,center.y, radius);
}
cvNamedWindow("circles", 1);
cvShowImage("circles", rgbcanny);
cvSaveImage("out.png", rgbcanny);
cvWaitKey(0);
我相信你有能力將它移植到 Python.
I trust you have the skills to port this to Python.
這篇關于OpenCV點目標檢測未找到所有目標，并且找到的圓圈偏移的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，也希望大家多多支持html5模板網！