自学教程：Python opencv操作深入详解

def display_img(file="p.jpeg"):  img = cv.imread(file)  print (img.shape)  cv.imshow('image',img)  cv.waitKey(0)  cv.destroyAllWindows()

def display_gray_img(file="p.jpeg"):  img = cv.imread(file,cv.IMREAD_GRAYSCALE)  print (img.shape)  cv.imshow('image',img)  cv.waitKey(0)  cv.destroyAllWindows()  cv.imwrite("gray_img.png",img)

def display_video(file="sj.mp4"):  v = cv.VideoCapture(file)  if v.isOpened():    open,frame = v.read()  else:    open=False  while open:    ret,frame = v.read()    if frame is None:      break      if ret == True:      gray = cv.cvtColor(frame,cv.COLOR_BGR2GRAY)      cv.imshow("result",gray)      if cv.waitKey(10) & 0xFF == 27:        break  v.release()  v.waitKey(0)  v.destroyAllWindows()

def get_frame_img(file="p.jpeg"):  img = cv.imread(file)  print (img.shape)  cat = img[0:200,0:200]  cv.imshow('get_frame_img',cat)  cv.waitKey(0)  cv.destroyAllWindows()

def extrats_rgb_img(file="p.jpeg"):  img = cv.imread(file)  b,g,r = cv.split(img)  print (b.shape,g.shape,r.shape)  new_img = cv.merge((b,g,r))  print (new_img.shape)  copy_img_r = img.copy()  copy_img_r[:,:,0]=0  copy_img_r[:,:,1]=0  cv.imshow("r_img",copy_img_r)  copy_img_g = img.copy()  copy_img_g[:,:,0]=0  copy_img_g[:,:,2]=0  cv.imshow("g_img",copy_img_g)  copy_img_b = img.copy()  copy_img_b[:,:,1]=0  copy_img_b[:,:,2]=0  cv.imshow("b_img",copy_img_b)

def border_fill_img(file="p.jpeg"):  border_type = [    cv.BORDER_REPLICATE,#复制法，复制边缘    cv.BORDER_REFLECT, #反射法，对感兴趣的图像中的像素在两边进行复制    cv.BORDER_REFLECT_101,#反射法，以边缘像素为轴，对称    cv.BORDER_WRAP,#外包装法    cv.BORDER_CONSTANT#常量法，常量填充    ]  border_title = [    "REPLICATE",    "REFLECT",    "REFLECT_101",    "WRAP",    "CONSTANT"    ]  img = cv.imread(file)  top_size,bottom_size,left_size,right_size = (50,50,50,50)  plt.subplot(231)  plt.imshow(img,"gray")#原始图像  plt.title("ORIGNAL")  for i in range(len(border_type)):    result = cv.copyMakeBorder(img,top_size,bottom_size,left_size,right_size,border_type[i])    plt.subplot(232+i)    plt.imshow(result,"gray")    plt.title(border_title[i])  plt.show()

def img_compose(file1="tu.jpeg",file2="gui.jpeg"):  img_1 = cv.imread(file1)  img_2 = cv.imread(file2)  print (img_1.shape)  print (img_2.shape)  img_1= cv.resize(img_1,(500,500))  img_2= cv.resize(img_2,(500,500))  print (img_1.shape)  print (img_2.shape)  res = cv.addWeighted(img_1,0.4,img_2,0.6,0)  plt.imshow(res)  plt.show()  res = cv.resize(img_1,(0,0),fx=3,fy=1)  plt.imshow(res)  plt.show()  res = cv.resize(img_2,(0,0),fx=1,fy=3)  plt.imshow(res)  plt.show()

def Binarization(filepath):  img = cv2.imread(filepath,0)  limit = 120  ret,thresh=cv2.threshold(img,limit,255,cv2.THRESH_BINARY_INV)  plt.imshow(thresh,'gray')  plt.show()  return threshBinarization('t1.jpg')