opencv源码 python
opencv官方文档源码及注释
# -*- coding: UTF-8 -*-
import cv2
import numpy as np
from matplotlib import pyplot as plt
# I = cv2.imread('C:/Users/the_moon/Desktop/image.bmp',0)#读取图片
# cv2.namedWindow('I',cv2.WINDOW_NORMAL) #重新指定窗口形状
# cv2.imshow('image',I) #image 为显示框名字，I为显示的图片
# h=I.shape[0]
# w=I.shape[1]
# I1=np.zeros((w,h))
# cv2.imshow('1',I)
##创建蓝色线条
# # Create a black image
# img = np.zeros((512,512,3), np.uint8)
# # Draw a diagonal blue line with thickness of 5 px
# img = cv2.line(img,(0,0),(511,511),(255,0,0),5)#img为图像矩阵，（0，0），（511，511）范围，（255，0，0）指定蓝色，5为厚度
# cv2.imshow('img',img)
# #随轨迹创建调色板
# def nothing(x):
# pass
# # Create a black image, a window
img = cv2.imread('C:/Users/the_moon/Desktop/image.bmp')
plt.subplot(131),plt.imshow(img),plt.title('ORIGINAL1')
# cv2.namedWindow('image')
# # create trackbars for color change
# cv2.createTrackbar('R','image',0,255,nothing)
# cv2.createTrackbar('G','image',0,255,nothing)
# cv2.createTrackbar('B','image',0,255,nothing)
# # create switch for ON/OFF functionality
# switch = '0 : OFF \n1 : ON'
# cv2.createTrackbar(switch, 'image',0,1,nothing)
# while(1):
# cv2.imshow('image',img)
# k = cv2.waitKey(1) & 0xFF
# if k == 27:
# break
# # get current positions of four trackbars
# r = cv2.getTrackbarPos('R','image')
# g = cv2.getTrackbarPos('G','image')
# b = cv2.getTrackbarPos('B','image')
# s = cv2.getTrackbarPos(switch,'image')
# if s == 0:
# img[:] = 0
# else:
# img[:] = [b,g,r]
img = cv2.imread('C:/Users/the_moon/Desktop/image.bmp')
# cv2.imshow('image3',img)
img.itemset((10,10,2),100)
# cv2.namedWindow('image3',cv2.WINDOW_NORMAL)
x,y,z=img.shape #图片矩阵的形状
print(x,y,z,img.size,img.dtype)#img.size是图片像素总和,什么类型
b,g,r=cv2.split(img)#单独提出B,G,R三通道
img=cv2.merge((b,g,r))
#img[:,:,1]=255#提取出单通道，并赋值新的颜色，0，1，2代表蓝，绿，红
#填充图片边框
"""
cv2.copyMakeBorder()
src ：input image
top, bottom, left, right ：border width in number of pixels in corresponding directions
borderType ：Flag defining what kind of border to be added. It can be following types:
cv2.BORDER_CONSTANT ：Adds a constant colored border. The value should be given as next argument.
cv2.BORDER_REFLECT ： Border will be mirror reflection of the border elements, like this : fedcba|abcdefgh|hgfedcb
cv2.BORDER_REFLECT_101 or cv2.BORDER_DEFAULT ： Same as above, but with a slight change, like this : gfedcb|abcdefgh|gfedcba
cv2.BORDER_REPLICATE ： Last element is replicated throughout, like this: aaaaaa|abcdefgh|hhhhhhh
cv2.BORDER_WRAP ： Can’t explain, it will look like this : cdefgh|abcdefgh|abcdefg
value ： Color of border if border type is cv2.BORDER_CONSTANT
"""
# replicate=cv2.copyMakeBorder(img,100,100,100,100,cv2.BORDER_REPLICATE)
# reflect=cv2.copyMakeBorder(img,100,100,100,100,cv2.BORDER_REFLECT)
# wrap=cv2.copyMakeBorder(img,100,100,100,100,cv2.BORDER_WRAP)
# constant=cv2.copyMakeBorder(img,100,100,100,100,cv2.BORDER_CONSTANT)
# reflect101 = cv2.copyMakeBorder(img,100,100,100,100,cv2.BORDER_REFLECT_101)
# plt.subplot(231),plt.imshow(img),plt.title('ORIGINAL')
# plt.subplot(232),plt.imshow(replicate),plt.title('REPLICATE')
# plt.subplot(233),plt.imshow(reflect),plt.title('REFLECT')
# plt.subplot(234),plt.imshow(reflect101),plt.title('REFLECT_101')
# plt.subplot(235),plt.imshow(wrap),plt.title('WRAP')
# plt.subplot(236),plt.imshow(constant),plt.title('CONSTANT')
# plt.show()
# #两张图片叠加
img2=cv2.imread('C:/Users/the_moon/Desktop/lena.BMP')
# dst = cv2.addWeighted(img,0.7,img,0.3,0)
#按位操作对图片叠加
# I want to put logo on top-left corner, So I create a ROI
rows,cols,channels = img.shape
roi = img[0:rows, 0:cols ]
# Now create a mask of logo and create its inverse mask also
img2gray = cv2.cvtColor(img2,cv2.COLOR_BGR2GRAY) #用这个函数把图像从RGB转到HSV夜色空间，注意是BGR2HSV，因为在opencv中默认的颜色空间是BGR。
ret, mask = cv2.threshold(img2gray, 150, 255, cv2.THRESH_BINARY)#threshold：固定阈值二值化，ret, dst = cv2.threshold(src, thresh, maxval,type)src： 输入图，只能输入单通道图像，通常来说为灰度图dst： 输出图thresh： 阈值maxval： 当像素值超过了阈值（或者小于阈值，根据type来决定），所赋予的值type：二值化操作的类型，包含以下5种类型： cv2.THRESH_BINARY； cv2.THRESH_BINARY_INV； cv2.THRESH_TRUNC； cv2.THRESH_TOZERO；cv2.THRESH_TOZERO_INV
"""bitwise_and是对二进制数据进行“与”操作，即对图像（灰度图像或彩色图像均可）每个像素值进行二进制“与”操作，1&1=1，1&0=0，0&1=0，0&0=0
bitwise_or是对二进制数据进行“或”操作，即对图像（灰度图像或彩色图像均可）每个像素值进行二进制“或”操作，1|1=1，1|0=0，0|1=0，0|0=0
bitwise_xor是对二进制数据进行“异或”操作，即对图像（灰度图像或彩色图像均可）每个像素值进行二进制“异或”操作，1^1=0,1^0=1,0^1=1,0^0=0
bitwise_not是对二进制数据进行“非”操作，即对图像（灰度图像或彩色图像均可）每个像素值进行二进制“非”操作，~1=0，~0=1
"""
mask_inv = cv2.bitwise_not(mask)
# Now black-out the area of logo in ROI
img1_bg = cv2.bitwise_and(roi,roi,mask = mask_inv)
# Take only region of logo from logo image.
img2_fg = cv2.bitwise_and(img2,img2,mask = mask)
# Put logo in ROI and modify the main image
dst = cv2.add(img1_bg,img2_fg)
img[0:rows, 0:cols ] = dst
plt.subplot(132),plt.imshow(img2),plt.title('ORIGINAL2')
plt.subplot(133),plt.imshow(dst),plt.title('Image Blending')
plt.show()
# cv2.imshow('image3_after',dst)
# cv2.namedWindow('image3_after',cv2.WINDOW_NORMAL)
#
# #结束条件
# k=cv2.waitKey(0)#等待时间，ms
# if k ==27: #当ESC按下时退出
# print('退出')
# cv2.destroyAllWindows()
# elif k==ord('s'):#如果按下键盘S则保存并退出
# cv2.imwrite('image2.bmp', I) # 储存图片，第一个参数为图片名字和格式，第二个为要存储图片的对象
# print('已保存图片')
# cv2.destroyAllWindows()#任意键盘键关闭所有窗口
#