Python-opencv学习第三十课：人脸检测
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Python-opencv学习第三十课：人脸检测
一、学习部分
记录笔者学习Python-opencv学习第三十课：人脸检测，代码资料来源于网络贾老师视频。
二、代码部分
1.引入库
代码如下：
import cv2 as cv
import matplotlib.pyplot as plt
import numpy as np
2.完整代码
代码如下：
import cv2 as cv
import numpy as np
from matplotlib import pyplot as plt
def read_demo():
image = cv.imread("D:/images/test.png") # BGR, 0~255
# cv.namedWindow("input", cv.WINDOW_AUTOSIZE)
cv.imshow("input", image)
cv.waitKey(0)
cv.destroyAllWindows()
def color_space_demo():
image = cv.imread("D:/images/test.png") # BGR, 0~255
gray = cv.cvtColor(image, cv.COLOR_BGR2GRAY)
hsv = cv.cvtColor(image, cv.COLOR_HSV2BGR) # H 0 ~180
# cv.namedWindow("input", cv.WINDOW_AUTOSIZE)
cv.imshow("gray", gray)
cv.imshow("hsv", hsv)
cv.waitKey(0)
cv.destroyAllWindows()
def mat_demo():
image = cv.imread("D:/images/test.png") # BGR, 0~255
h,w,c = image.shape
roi = image[60:200, 60:280, :]
blank = np.zeros((h, w, c), dtype=np.uint8)
# blank[60:200, 60:280, :] = image[60:200, 60:280, :]
blank = image # np.copy(image)
cv.imshow("blank", blank)
cv.imshow("roi", roi)
cv.waitKey(0)
cv.destroyAllWindows()
def pixel_demo():
image = cv.imread("D:/images/test.png") # BGR, 0~255
cv.imshow("input", image)
h,w,c = image.shape
for row in range(h):
for col in range(w):
b,g,r = image[row, col]
image[row, col] = (0, g, r)
cv.imshow("result", image)
cv.imwrite("D:/image_result.png", image)
cv.waitKey(0)
cv.destroyAllWindows()
def math_demo():
image = cv.imread("D:/images/test.png") # BGR, 0~255
cv.imshow("input", image)
h,w,c = image.shape
blank = np.zeros_like(image)
blank[:,:] = (2, 2, 2)
cv.imshow("blank", blank)
result = cv.multiply(image, blank)
cv.imshow("result", result)
cv.waitKey(0)
cv.destroyAllWindows()
def nothing(x):
print(x)
def adjust_lightness_demo():
image = cv.imread("D:/images/test.png") # BGR, 0~255
cv.namedWindow("input", cv.WINDOW_AUTOSIZE)
cv.createTrackbar("lightness", "input", 0, 100, nothing)
cv.imshow("input", image)
blank = np.zeros_like(image)
while True:
pos = cv.getTrackbarPos("lightness", "input")
blank[:,:] = (pos, pos, pos)
# cv.imshow("blank", blank)
result = cv.add(image, blank)
cv.imshow("result", result)
c = cv.waitKey(1)
if c == 27:
break
cv.destroyAllWindows()
def adjust_contrast_demo():
image = cv.imread("D:/images/test.png") # BGR, 0~255
cv.namedWindow("input", cv.WINDOW_AUTOSIZE)
cv.createTrackbar("lightness", "input", 0, 100, nothing)
cv.createTrackbar("contrast", "input", 100, 200, nothing)
cv.imshow("input", image)
blank = np.zeros_like(image)
while True:
light = cv.getTrackbarPos("lightness", "input")
contrast = cv.getTrackbarPos("contrast", "input") / 100
print("light: ", light, "contrast: ", contrast)
result = cv.addWeighted(image, contrast, blank, 0.5, light)
cv.imshow("result", result)
c = cv.waitKey(1)
if c == 27:
break
cv.destroyAllWindows()
def keys_demo():
image = cv.imread("D:/images/test.png") # BGR, 0~255
cv.namedWindow("input", cv.WINDOW_AUTOSIZE)
cv.imshow("input", image)
while True:
c = cv.waitKey(1)
if c == 49: #1
gray = cv.cvtColor(image, cv.COLOR_BGR2GRAY)
cv.imshow("result", gray)
if c == 50: #2
hsv = cv.cvtColor(image, cv.COLOR_BGR2HSV)
cv.imshow("result", hsv)
if c == 51: # 3
invert = cv.bitwise_not(image)
cv.imshow("result", invert)
if c == 27:
break
cv.destroyAllWindows()
def color_table_demo():
colormap = [
cv.COLORMAP_AUTUMN,
cv.COLORMAP_BONE,
cv.COLORMAP_JET,
cv.COLORMAP_WINTER,
cv.COLORMAP_RAINBOW,
cv.COLORMAP_OCEAN,
cv.COLORMAP_SUMMER,
cv.COLORMAP_SPRING,
cv.COLORMAP_COOL,
cv.COLORMAP_PINK,
cv.COLORMAP_HOT,
cv.COLORMAP_PARULA,
cv.COLORMAP_MAGMA,
cv.COLORMAP_INFERNO,
cv.COLORMAP_PLASMA,
cv.COLORMAP_VIRIDIS,
cv.COLORMAP_CIVIDIS,
cv.COLORMAP_TWILIGHT,
cv.COLORMAP_TWILIGHT_SHIFTED ]
image = cv.imread("D:/images/canjian.jpg") # BGR, 0~255
cv.namedWindow("input", cv.WINDOW_AUTOSIZE)
cv.imshow("input", image)
index = 0
while True:
dst = cv.applyColorMap(image, colormap[index%19])
index += 1
cv.imshow("color style", dst);
c = cv.waitKey(400)
if c == 27:
break
cv.destroyAllWindows()
def bitwise_demo():
b1 = np.zeros((400, 400, 3), dtype=np.uint8)
b1[:,:] = (255, 0, 255)
b2 = np.zeros((400, 400, 3), dtype=np.uint8)
b2[:,:] = (0, 255, 255)
cv.imshow("b1", b1);
cv.imshow("b2", b2);
dst1 = cv.bitwise_and(b1, b2)
dst2 = cv.bitwise_or(b1, b2)
cv.imshow("bitwise_and", dst1)
cv.imshow("bitwise_or", dst2)
cv.waitKey(0)
cv.destroyAllWindows()
def channels_split_demo():
b1 = cv.imread("D:/images/lena.jpg")
print(b1.shape)
cv.imshow("input", b1)
cv.imshow("b1", b1[:,:,2])
mv = cv.split(b1)
mv[0][:,:] = 255
result = cv.merge(mv)
dst = np.zeros(b1.shape, dtype=np.uint8)
cv.mixChannels([b1], [dst], fromTo=[2, 0, 1, 1, 0, 2])
cv.imshow("output4", dst)
cv.imshow("result",result)
cv.waitKey(0)
cv.destroyAllWindows()
def color_space_demo():
b1 = cv.imread("D:/images/greenback.png")
print(b1.shape)
cv.imshow("input", b1)
hsv = cv.cvtColor(b1, cv.COLOR_BGR2HSV)
cv.imshow("hsv", hsv)
mask = cv.inRange(hsv, (35, 43, 46), (77, 255, 255))
cv.bitwise_not(mask, mask)
result = cv.bitwise_and(b1, b1, mask=mask)
cv.imshow("result", result)
cv.waitKey(0)
cv.destroyAllWindows()
def pixel_stat_demo():
b1 = cv.imread("D:/images/1024.png")
print(b1.shape)
cv.imshow("input", b1)
print(np.max(b1[:,:,2]))
means, dev = cv.meanStdDev(b1)
print(means, "dev: ", dev)
cv.waitKey(0)
cv.destroyAllWindows()
def drawing_demo():
b1 = cv.imread("D:/images/1024.png")#np.zeros((512, 512, 3), dtype=np.uint8)
temp = np.copy(b1)
cv.rectangle(b1, (50, 50), (400, 400), (0, 0, 255), 4, 8, 0)
# cv.circle(b1, (200, 200), 100, (255, 0, 0), -1, 8, 0)
# cv.line(b1, (50, 50), (400, 400), (0, 255, 0), 4, 8, 0)
cv.putText(b1, "99% face", (50, 50), cv.FONT_HERSHEY_SIMPLEX, 1.0, (0, 255, 255), 2, 8)
cv.imshow("input", b1)
cv.waitKey(0)
cv.destroyAllWindows()
def random_color_demo():
b1 = np.zeros((512, 512, 3), dtype=np.uint8)
while True:
xx = np.random.randint(0, 512, 2, dtype=np.int)
yy = np.random.randint(0, 512, 2, dtype=np.int)
bgr = np.random.randint(0, 255, 3, dtype=np.int32)
print(bgr[0], bgr[1], bgr[2])
cv.line(b1, (xx[0], yy[0]), (xx[1], yy[1]), (np.int(bgr[0]), np.int(bgr[1]), np.int(bgr[2])), 1, 8, 0)
cv.imshow("input", b1)
c = cv.waitKey(10)
if c == 27:
break
cv.destroyAllWindows()
def polyline_drawing_demo():
canvas = np.zeros((512, 512, 3), dtype=np.uint8)
pts = np.array([[100, 100], [350, 100], [450, 280], [320, 450], [80, 400]在 django（使用 python-opencv）项目中找不到人脸（人脸检测）