first

test00_hello.py

@@ -0,0 +1,12 @@
+
+import cv2
+
+print(cv2.getVersionString())
+
+image = cv2.imread("opencv_logo.jpg")
+print(image.shape)
+
+
+cv2.imshow("image", image)
+cv2.waitKey()
+

test02_color.py

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+
+
+import cv2
+
+image = cv2.imread("opencv_logo.jpg")
+
+cv2.imshow("blue", image[:, :, 0])
+cv2.imshow("green", image[:, :, 1])
+cv2.imshow("red", image[:, :, 2])
+
+gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
+cv2.imshow("gray", gray)
+
+cv2.waitKey()
+

test03_crop.py

@@ -0,0 +1,9 @@
+
+import cv2
+
+image = cv2.imread("opencv_logo.jpg")
+
+crop = image[10:170, 40:200]
+
+cv2.imshow("crop", crop)
+cv2.waitKey()

test04_draw.py

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+
+import cv2
+import numpy as np
+
+image = np.zeros([300, 300, 3], dtype=np.uint8)
+
+cv2.line(image, (100, 200), (250, 250), (255, 0, 0), 2)
+cv2.rectangle(image, (30, 100), (60, 150), (0, 255, 0), 2)
+cv2.circle(image, (150, 100), 20, (0, 0, 255), 3)
+cv2.putText(image, "hello", (100, 50), 0, 1, (255, 255, 255), 2, 1)
+
+cv2.imshow("image", image)
+cv2.waitKey()

test05_blur.py

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+
+import cv2
+
+image = cv2.imread("plane.jpg")
+
+gauss = cv2.GaussianBlur(image, (5, 5), 0)
+median = cv2.medianBlur(image, 5)
+
+cv2.imshow("image", image)
+cv2.imshow("gauss", gauss)
+cv2.imshow("median", median)
+
+cv2.waitKey()
+

test06_corner.py

@@ -0,0 +1,13 @@
+
+import cv2
+
+image = cv2.imread("opencv_logo.jpg")
+gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
+
+corners = cv2.goodFeaturesToTrack(gray, 500, 0.1, 10)
+for corner in corners:
+    x, y = corner.ravel()
+    cv2.circle(image, (int(x), int(y)), 3, (255, 0, 255), -1)
+
+cv2.imshow("corners", image)
+cv2.waitKey()

test07_match.py

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+
+import cv2
+import numpy as np
+
+image = cv2.imread("poker.jpg")
+gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
+
+template = gray[75:105, 235:265]
+
+match = cv2.matchTemplate(gray, template, cv2.TM_CCOEFF_NORMED)
+locations = np.where(match >= 0.9)
+
+w, h = template.shape[0:2]
+for p in zip(*locations[::-1]):
+    x1, y1 = p[0], p[1]
+    x2, y2 = x1 + w, y1 + h
+    cv2.rectangle(image, (x1, y1), (x2, y2), (0, 255, 0), 2)
+
+cv2.imshow("image", image)
+cv2.waitKey()
+
+

test08_gradient.py

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+
+import cv2
+
+gray = cv2.imread("opencv_logo.jpg", cv2.IMREAD_GRAYSCALE)
+
+laplacian = cv2.Laplacian(gray, cv2.CV_64F)
+canny = cv2.Canny(gray, 100, 200)
+
+cv2.imshow("gray", gray)
+cv2.imshow("laplacian", laplacian)
+cv2.imshow("canny", canny)
+
+cv2.waitKey()
+

test09_threshold.py

@@ -0,0 +1,16 @@
+
+import cv2
+
+gray = cv2.imread("bookpage.jpg", cv2.IMREAD_GRAYSCALE)
+ret, binary = cv2.threshold(gray, 10, 255, cv2.THRESH_BINARY)
+binary_adaptive = cv2.adaptiveThreshold(
+    gray, 255, cv2.ADAPTIVE_THRESH_GAUSSIAN_C, cv2.THRESH_BINARY, 115, 1)
+ret1, binary_otsu = cv2.threshold(gray, 0, 255, cv2.THRESH_BINARY + cv2.THRESH_OTSU)
+
+cv2.imshow("gray", gray)
+cv2.imshow("binary", binary)
+cv2.imshow("adaptive", binary_adaptive)
+cv2.imshow("otsu", binary_otsu)
+
+cv2.waitKey()
+

test10_morphology.py

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+
+import cv2
+import numpy as np
+
+gray = cv2.imread("opencv_logo.jpg", cv2.IMREAD_GRAYSCALE)
+
+_, binary = cv2.threshold(gray, 200, 255, cv2.THRESH_BINARY_INV)
+kernel = np.ones((5, 5), np.uint8)
+
+erosion = cv2.erode(binary, kernel)
+dilation = cv2.dilate(binary, kernel)
+
+cv2.imshow("binary", binary)
+cv2.imshow("erosion", erosion)
+cv2.imshow("dilation", dilation)
+
+
+cv2.waitKey()

test11_camera.py

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+
+import cv2
+
+capture = cv2.VideoCapture(0)
+
+while True:
+    ret, frame = capture.read()
+    cv2.imshow("camera", frame)
+    key = cv2.waitKey(1)
+    if key != -1:
+        break
+
+capture.release()
+