现在我致力于从 OpenData 生成道路标记。因为我是编程新手,所以我使用 Python。我处理正射影像并将它们转换为二值照片(仅黑白像素)。之后我得到这样的照片:
下一步是识别给定示例图片上的各种道路标记。我认为这应该可以通过“形状上下文匹配”来实现。
所以我写了这段代码(a
是原始的转向箭头,
b
是从示例图片中提取的转向箭头)来比较这里的各种转向箭头和原始转向箭头:
import cv2
import numpy as np
# read data
datapath = "/Users/output/test/";
a = cv2.imread(datapath+"template_orig.png",0);
b = cv2.imread(datapath+"template.png",0);
# find contours
ca = cv2.findContours(a, cv2.RETR_CCOMP, cv2.CHAIN_APPROX_TC89_KCOS)
cb = cv2.findContours(b, cv2.RETR_CCOMP, cv2.CHAIN_APPROX_TC89_KCOS)
print(np.shape(ca[0]), np.shape(cb[0]))
# generate distance --> Hausdorff OR ShapeContext
hd = cv2.createHausdorffDistanceExtractor()
sd = cv2.createShapeContextDistanceExtractor()
d1 = hd.computeDistance(ca[0],cb[0])
d2 = sd.computeDistance(ca[0],cb[0])
print d1, " ", d2
但是当我想执行我的代码时,它会说:
cv2.error: /Users/travis/build/skvark/opencv-python/opencv/modules/shape/src/haus_dis.cpp:139: 错误: (-215) (set1.channels()==2) && (set1 .cols>0) 在函数 computeDistance
“a”的分辨率是:32 x 131 px ,“b”的分辨率是:18 x 29 px ,这是否还有问题?
谢谢你的努力 :)
编辑:
我将代码更改为以下内容:
import cv2
import numpy as np
# read data
datapath = "/Users/output/test/";
a = cv2.imread(datapath+"template_orig.png");
b = cv2.imread(datapath+"template.png");
imgray_a = cv2.cvtColor(a,cv2.COLOR_BGR2GRAY)
ret_a,thresh_a = cv2.threshold(imgray_a,127,255,0)
imgray_b = cv2.cvtColor(b,cv2.COLOR_BGR2GRAY)
ret_b,thresh_b = cv2.threshold(imgray_b,127,255,0)
# find contours
_, ca, _ = cv2.findContours(thresh_a, cv2.RETR_CCOMP, cv2.CHAIN_APPROX_SIMPLE)
_, cb, _ = cv2.findContours(thresh_b, cv2.RETR_CCOMP, cv2.CHAIN_APPROX_SIMPLE)
print(np.shape(ca[0]), np.shape(cb[0]))
# generate distance --> Hausdorff OR ShapeContext
hd = cv2.createHausdorffDistanceExtractor()
sd = cv2.createShapeContextDistanceExtractor()
d1 = hd.computeDistance(ca[0],cb[0])
d2 = sd.computeDistance(ca[0],cb[0])
print d1, " ", d2
a和b比较的结果是:d1 = 28.4604988098, d2 = 0.320339113474
但是当我将a与例如c ( ) 进行比较时,程序会因以下错误而停止:
cv2.error: /Users/travis/build/skvark/opencv-python/opencv/modules/core/src/matmul.cpp:1218: 错误: (-215) type == CV_64FC2 in function gemmImpl