import cv2 import numpy as np def cv_show(name,img): cv2.imshow(name,img) cv2.waitKey() cv2.destroyAllWindows() def get_img(path1,path2): img1 = cv2.imread(path1) img2 = cv2.imread(path2) #原图像变换为灰度图 img1_gray = cv2.cvtColor(img1, cv2.COLOR_BGR2GRAY) img2_gray = cv2.cvtColor(img2, cv2.COLOR_BGR2GRAY) return img1,img2,img1_gray,img2_gray def get_info(img1_gray,img2_gray): # 尺度不变特征变换 sift = cv2.SIFT_create() # 关键点以及特征向量计算 kp1, des1 = sift.detectAndCompute(img1_gray, None) kp2, des2 = sift.detectAndCompute(img2_gray, None) kp1 = np.float32([kp.pt for kp in kp1]) kp2 = np.float32([kp.pt for kp in kp2]) return kp1,des1,kp2,des2 def get_match(kp1,kp2,des1,des2): # 特征点交叉检验 bf = cv2.BFMatcher() matches = bf.knnMatch(des1, des2,k=2) idx_pair=[] for m,n in matches: if m.distance<n.distance*0.75: idx_pair.append((m.queryIdx,m.trainIdx)) if len(idx_pair)>4: pt_list1 = np.float32([kp1[i] for (i, _) in idx_pair]) pt_list2 = np.float32([kp1[i] for (_, i) in idx_pair]) H,_ = cv2.findHomography(pt_list2,pt_list1,cv2.RANSAC,4) result = cv2.warpPerspective(img2, H, (img1.shape[1] + img2.shape[1], img1.shape[0])) result[0:img1.shape[0], 0:img1.shape[1]] = img1 return result #main函数 path1='img1.jpg' path2='img2.jpg' img1,img2,img1_gray,img2_gray=get_img(path1,path2) kp1,des1,kp2,des2=get_info(img1_gray,img2_gray) result=get_match(kp1,des1,kp2,des2) cv_show('result',result)

这段代码是一个基于SIFT特征点匹配的图像拼接代码。代码中先读取了两张图片，然后将其转换为灰度图像，并利用SIFT算法提取各自的关键点和特征向量，之后利用BFMatcher进行特征点匹配，再进行交叉检验，得到匹配点对，进而利用findHomography计算出变换矩阵H，最后利用warpPerspective函数将图像2变换到图像1的位置，并将两幅图像拼接在一起。最后使用cv_show函数显示拼接后的图像。

需要注意的是，SIFT算法是一种有专利的算法，如果使用OpenCV 3.4.2及以后的版本，需要安装opencv-contrib-python才能使用SIFT算法。如果没有安装该库，可以使用SURF算法代替SIFT算法进行特征提取。同时，该代码还存在一些问题，比如在利用findHomography计算变换矩阵时，应该将pt_list2放在前面，pt_list1放在后面，否则会导致拼接的结果不正确。此外，在利用warpPerspective函数变换图像时，应该先将变换矩阵H取反，否则得到的结果也会不正确。

相关问题

import numpy as np import cv2 class ColorMeter(object): color_hsv = { # HSV，H表示色调（度数表示0-180），S表示饱和度（取值0-255），V表示亮度（取值0-255） # "orange": [np.array([11, 115, 70]), np.array([25, 255, 245])], "yellow": [np.array([11, 115, 70]), np.array([34, 255, 245])], "green": [np.array([35, 115, 70]), np.array([77, 255, 245])], "lightblue": [np.array([78, 115, 70]), np.array([99, 255, 245])], "blue": [np.array([100, 115, 70]), np.array([124, 255, 245])], "purple": [np.array([125, 115, 70]), np.array([155, 255, 245])], "red": [np.array([156, 115, 70]), np.array([179, 255, 245])], } def __init__(self, is_show=False): self.is_show = is_show self.img_shape = None def detect_color(self, frame): self.img_shape = frame.shape res = {} # 将图像转化为HSV格式 hsv = cv2.cvtColor(frame, cv2.COLOR_BGR2HSV) for text, range_ in self.color_hsv.items(): # 去除颜色范围外的其余颜色 mask = cv2.inRange(hsv, range_[0], range_[1]) erosion = cv2.erode(mask, np.ones((1, 1), np.uint8), iterations=2) dilation = cv2.dilate(erosion, np.ones((1, 1), np.uint8), iterations=2) target = cv2.bitwise_and(frame, frame, mask=dilation) # 将滤波后的图像变成二值图像放在binary中 ret, binary = cv2.threshold(dilation, 127, 255, cv2.THRESH_BINARY) # 在binary中发现轮廓，轮廓按照面积从小到大排列 contours, hierarchy = cv2.findContours( binary, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE ) if len(contours) > 0: # cv2.boundingRect()返回轮廓矩阵的坐标值，四个值为x, y, w, h， 其中x, y为左上角坐标，w,h为矩阵的宽和高 boxes = [ box for box in [cv2.boundingRect(c) for c in contours] if min(frame.shape[0], frame.shape[1]) / 10 < min(box[2], box[3]) < min(frame.shape[0], frame.shape[1]) / 1 ] if boxes: res[text] = boxes if self.is_show: for box in boxes: x, y, w, h = box # 绘制矩形框对轮廓进行定位 cv2.rectangle( frame, (x, y), (x + w, y + h), (153, 153, 0), 2 ) # 将绘制的图像保存并展示 # cv2.imwrite(save_image, img) cv2.putText( frame, # image text, # text (x, y), # literal direction cv2.FONT_HERSHEY_SIMPLEX, # dot font 0.9, # scale (255, 255, 0), # color 2, # border ) if self.is_show: cv2.imshow("image", frame) cv2.waitKey(1) # cv2.destroyAllWindows() return res if __name__ == "__main__": cap = cv2.VideoCapture(0) m = ColorMeter(is_show=True) while True: success, frame = cap.read() res = m.detect_color(frame) print(res) if cv2.waitKey(1) & 0xFF == ord('q'): break

"red": (0, 255, 255),
"green": (85, 255, 128),
"blue": (170, 255, 128) } 你好！我能够理解你正在询问的是如何使用HSV色彩空间来表示不同的颜色。例如，红色的HSV值为（0，255，255），绿色的HSV值为（85，255，128），蓝色的HSV值为（170，255，128）。

修改此代码使其可重复运行import pygame import sys from pygame.locals import * from robomaster import * import cv2 import numpy as np focal_length = 750 # 焦距 known_radius = 2 # 已知球的半径 def calculate_distance(focal_length, known_radius, perceived_radius): distance = (known_radius * focal_length) / perceived_radius return distance def show_video(ep_robot, screen): 获取机器人第一视角图像帧 img = ep_robot.camera.read_cv2_image(strategy="newest") 转换图像格式，转换为pygame的surface对象 img = cv2.cvtColor(img, cv2.COLOR_BGR2RGB) img = cv2.transpose(img) # 行列互换 img = pygame.surfarray.make_surface(img) screen.blit(img, (0, 0)) # 绘制图像 def detect_white_circle(ep_robot): 获取机器人第一视角图像帧 img = ep_robot.camera.read_cv2_image(strategy="newest") 转换为灰度图像 gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY) 进行中值滤波处理 gray = cv2.medianBlur(gray, 5) 检测圆形轮廓 circles = cv2.HoughCircles(gray, cv2.HOUGH_GRADIENT, 1, 50, param1=160, param2=40, minRadius=5, maxRadius=60) if circles is not None: circles = np.uint16(np.around(circles)) for circle in circles[0, :]: center = (circle[0], circle[1]) known_radius = circle 在图像上绘制圆形轮廓 cv2.circle(img, center, known_radius, (0, 255, 0), 2) 显示图像 distance = calculate_distance(focal_length, known_radius, known_radius) 在图像上绘制圆和距离 cv2.circle(img, center, known_radius, (0, 255, 0), 2) cv2.putText(img, f"Distance: {distance:.2f} cm", (center[0] - known_radius, center[1] - 10), cv2.FONT_HERSHEY_SIMPLEX, 0.5, (0, 255, 0), 2) cv2.imshow("White Circle Detection", img) cv2.waitKey(1) def main(): pygame.init() screen_size = width, height = 1280, 720 screen = pygame.display.set_mode(screen_size) ep_robot = robot.Robot() ep_robot.initialize(conn_type='ap') version = ep_robot.get_version() print("Robot version: {0}".format(version)) ep_robot.camera.start_video_stream(display=False) pygame.time.wait(100) clock = pygame.time.Clock() while True: clock.tick(5) # 将帧数设置为25帧 for event in pygame.event.get(): if event.type == QUIT: ep_robot.close() pygame.quit() sys.exit() show_video(ep_robot, screen) detect_white_circle(ep_robot) if name == 'main': main()

修改后的代码如下所示：

import pygame
import sys
from pygame.locals import *
import robomaster
import cv2
import numpy as np

focal_length = 750  # 焦距
known_radius = 2  # 已知球的半径


def calculate_distance(focal_length, known_radius, perceived_radius):
    distance = (known_radius * focal_length) / perceived_radius
    return distance


def show_video(ep_robot, screen):
    # 获取机器人第一视角图像帧
    img = ep_robot.camera.read_cv2_image(strategy="newest")

    # 转换图像格式，转换为pygame的surface对象
    img = cv2.cvtColor(img, cv2.COLOR_BGR2RGB)
    img = cv2.transpose(img)  # 行列互换
    img = pygame.surfarray.make_surface(img)
    screen.blit(img, (0, 0))  # 绘制图像


def detect_white_circle(ep_robot):
    # 获取机器人第一视角图像帧
    img = ep_robot.camera.read_cv2_image(strategy="newest")

    # 转换为灰度图像
    gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)

    # 进行中值滤波处理
    gray = cv2.medianBlur(gray, 5)

    # 检测圆形轮廓
    circles = cv2.HoughCircles(gray, cv2.HOUGH_GRADIENT, 1, 50, param1=160, param2=40, minRadius=5, maxRadius=60)
    if circles is not None:
        circles = np.uint16(np.around(circles