ret, thresh = cv2.threshold(edges, 127, 255, cv2.THRESH_BINARY)
时间: 2024-06-07 09:11:19 浏览: 19
这段代码使用了OpenCV库中的threshold函数,它的作用是将图像进行二值化处理。具体来说,将图像中灰度值大于阈值(这里是127)的像素点设为255(白色),灰度值小于等于阈值的像素点设为0(黑色)。这样就将图像转换为只有黑白两种颜色的二值图像,方便进行后续的图像处理。函数返回两个值,一个是处理后的二值图像,另一个是阈值。
相关问题
import cv2 import numpy as np # 加载图像 img = cv2.imread('color_blind_road_2.png') # 转换为灰度图像 gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY) # 直线检测 edges = cv2.Canny(gray, 50, 150, apertureSize=3) lines = cv2.HoughLinesP(edges, 1, np.pi/180, threshold=100, minLineLength=100, maxLineGap=10) for line in lines: x1, y1, x2, y2 = line[0] cv2.line(img, (x1, y1), (x2, y2), (0, 0, 255), 2) # 阈值分割 ret, thresh = cv2.threshold(gray, 150, 255, cv2.THRESH_BINARY) thresh = cv2.medianBlur(thresh, 5) # 彩色连续性空间分割 hsv = cv2.cvtColor(img, cv2.COLOR_BGR2HSV) h, s, v = cv2.split(hsv) mask = cv2.inRange(h, 0, 20) | cv2.inRange(h, 160, 180) mask = cv2.bitwise_and(thresh, mask) # 纹理分割 gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY) texture = cv2.Canny(gray, 100, 200, apertureSize=3) texture = cv2.dilate(texture, None, iterations=3) texture = cv2.erode(texture, None, iterations=3) texture = cv2.bitwise_and(thresh, texture) # 显示结果 cv2.imshow('img', img) cv2.imshow('thresh', thresh) cv2.imshow('color', mask) cv2.imshow('texture', texture) cv2.waitKey(0) cv2.destroyAllWindows()改进代码
以下是对代码的一些改进建议:
1. 在 import 语句之间添加空格,使代码更易于阅读。
2. 使用函数封装代码,将不同的操作分别放入不同的函数中,可以使代码更加清晰和易于维护。
3. 添加异常处理,以避免因为文件路径或读取失败而导致程序崩溃。
4. 将一些常量或者需要调整的参数提取出来,以方便后续调整和修改。
5. 添加注释,以便代码的阅读和理解。
6. 使用 with 语句释放资源。
改进后的代码如下:
```python
import cv2
import numpy as np
def load_image(path):
"""加载图片"""
try:
img = cv2.imread(path)
return img
except Exception as e:
print(e)
return None
def gray_transform(img):
"""灰度转换"""
gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
return gray
def edge_detection(img, threshold1=50, threshold2=150, apertureSize=3):
"""边缘检测"""
edges = cv2.Canny(img, threshold1, threshold2, apertureSize=apertureSize)
return edges
def line_detection(img, edges, threshold=100, minLineLength=100, maxLineGap=10):
"""直线检测"""
lines = cv2.HoughLinesP(edges, 1, np.pi/180, threshold=threshold, minLineLength=minLineLength, maxLineGap=maxLineGap)
for line in lines:
x1, y1, x2, y2 = line[0]
cv2.line(img, (x1, y1), (x2, y2), (0, 0, 255), 2)
return img
def threshold_segmentation(img, threshold=150):
"""阈值分割"""
ret, thresh = cv2.threshold(img, threshold, 255, cv2.THRESH_BINARY)
thresh = cv2.medianBlur(thresh, 5)
return thresh
def hsv_segmentation(img, lower_range, upper_range):
"""HSV颜色空间分割"""
hsv = cv2.cvtColor(img, cv2.COLOR_BGR2HSV)
mask = cv2.inRange(hsv, lower_range, upper_range)
return mask
def color_segmentation(img, thresh, lower_range1=(0, 100, 100), upper_range1=(20, 255, 255), lower_range2=(160, 100, 100), upper_range2=(180, 255, 255)):
"""颜色分割"""
mask1 = hsv_segmentation(img, lower_range1, upper_range1)
mask2 = hsv_segmentation(img, lower_range2, upper_range2)
mask = cv2.bitwise_or(mask1, mask2)
mask = cv2.bitwise_and(thresh, mask)
return mask
def texture_segmentation(img, thresh, threshold1=100, threshold2=200, iterations=3):
"""纹理分割"""
gray = gray_transform(img)
texture = cv2.Canny(gray, threshold1, threshold2, apertureSize=3)
texture = cv2.dilate(texture, None, iterations=iterations)
texture = cv2.erode(texture, None, iterations=iterations)
texture = cv2.bitwise_and(thresh, texture)
return texture
def show_image(img, winname='image'):
"""显示图片"""
cv2.imshow(winname, img)
cv2.waitKey(0)
cv2.destroyAllWindows()
if __name__ == '__main__':
# 加载图片
img = load_image('color_blind_road_2.png')
if img is None:
exit()
# 灰度转换
gray = gray_transform(img)
# 边缘检测
edges = edge_detection(gray)
# 直线检测
img = line_detection(img, edges)
# 阈值分割
thresh = threshold_segmentation(gray)
# 颜色分割
mask = color_segmentation(img, thresh)
# 纹理分割
texture = texture_segmentation(img, thresh)
# 显示结果
show_image(img, 'img')
show_image(thresh, 'thresh')
show_image(mask, 'color')
show_image(texture, 'texture')
```
img = cv2.imread('../maze3.png') # 灰度化、阈值分割、边缘检测 gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY) ret, thresh = cv2.threshold(gray, 127, 255, cv2.THRESH_BINARY) edges = cv2.Canny(thresh, 50, 150, apertureSize=3) # 霍夫变换检测直线 lines = cv2.HoughLines(edges, 1, np.pi/180, 100) # 绘制直线 if lines is not None and len(lines) > 0: for line in lines: rho, theta = line[0] a = np.cos(theta) b = np.sin(theta) x0 = a * rho y0 = b * rho x1 = int(x0 + 1000 * (-b)) y1 = int(y0 + 1000 * (a)) x2 = int(x0 - 1000 * (-b)) y2 = int(y0 - 1000 * (a)) # 判断直线是否在黑色区域内 if thresh[y1, x1] == 0 and thresh[y2, x2] == 0: cv2.line(img, (x1, y1), (x2, y2), (0, 0, 0), 2)
这段代码是对一张图片进行灰度化、阈值分割、边缘检测、霍夫变换检测直线、绘制直线的过程。在绘制直线的时候,会判断直线是否在黑色区域内,如果不在,则不绘制这条直线。
错误信息提示说 IndexError: index -1000 is out of bounds for axis 1 with size 588,说明在使用 thresh[y1, x1] 和 thresh[y2, x2] 进行判断时,出现了数组越界的问题,即坐标值超过了 thresh 数组的范围。
你可以尝试在判断之前,打印出 x1, y1, x2, y2 这四个值,看看是否有异常,以及其具体的数值。如果坐标值确实超出了范围,那么你可以检查一下代码中的变量,看看是否有误。另外,也可以检查一下原始图片的尺寸,是否与代码中的处理一致。