当前位置:网站首页>opencv学习笔记二——图像基本操作
opencv学习笔记二——图像基本操作
2022-07-07 05:19:00 【我是一个小稻米】
1. POI区域:感兴趣区域
2. 边缘填充
3. 数值运算
import cv2
import matplotlib.pyplot as plt
import matplotlib.image as mpimg
import numpy as np
from PIL import Image
image1 = mpimg.imread('1.jpg')
image2 = mpimg.imread('2.jpg')
plt.imshow(image1)
plt.imshow(image2)
图像加法
image3 = image1+image2
plt.imshow(image3)
图像裁剪
plt.imshow(image1[100:-100, 100:-100, :]);
图像缩放
fx和fy表示缩放倍数
image4 = cv2.resize(image1, (0, 0), fx=3, fy=1)
plt.imshow(image4);
4. 图像阈值
ret, dst = cv2.threshold(src, thresh, maxval, type)
- src: 输入图像,只能是单通道图像
- dst:输出图
- thresh:阈值
- maxval:当像素值超过了阈值或小于阈值时的取值
- type:二值化的类型
- cv2.THRESH_BINARY 超过阈值取maxval,否则取0
- cv2.THRESH_BINARY_INV THRESH_BINARY的反转
- cv2.THRESH_TRUNC 大于阈值设置阈值,其余不变
- cv2.THRESH_TOZERO 大于阈值不变,其余设为0
- cv2.THRESH_TOZERO_INV THRESH_TOZERO的反转
image1_gray = image1[:,:,0]
res, thresh1 = cv2.threshold(image1_gray, 127, 255, cv2.THRESH_BINARY)
res, thresh2 = cv2.threshold(image1_gray, 127, 255, cv2.THRESH_BINARY_INV)
res, thresh3 = cv2.threshold(image1_gray, 127, 255, cv2.THRESH_TRUNC)
res, thresh4 = cv2.threshold(image1_gray, 127, 255, cv2.THRESH_TOZERO)
res, thresh5 = cv2.threshold(image1_gray, 127, 255, cv2.THRESH_TOZERO_INV)
titles = ['Original Image', 'BINARY', 'BINARY_INV', 'TRUNC', 'TOZERO', 'TOZERO_INV']
images = [image1_gray, thresh1, thresh2, thresh3, thresh4, thresh5]
for i in range(6):
plt.subplot(2,3,i+1)
plt.imshow(images[i], 'gray')
plt.title(titles[i])
plt.xticks([])
plt.yticks([])
plt.show()
边栏推荐
- 机器人教育在动手实践中的真理
- 电池、电机技术受到很大关注,反而电控技术却很少被提及?
- CCTV is so warm-hearted that it teaches you to write HR's favorite resume hand in hand
- Function extension, attribute extension and non empty type extension in kotlin
- LeetCode简单题之找到一个数字的 K 美丽值
- 【无标题】
- 运放电路的反馈电阻上并联一个电容是什么作用
- Vulnerability recurrence easy_ tornado
- Hisense TV starts the developer mode
- Search for an element in a binary search tree (BST)
猜你喜欢
随机推荐
[quick start of Digital IC Verification] 12. Introduction to SystemVerilog testbench (svtb)
Linux Installation MySQL 8.0 configuration
Réplication de vulnérabilité - désrialisation fastjson
Four items that should be included in the management system of integral mall
Blob 对象介绍
[quick start of Digital IC Verification] 13. SystemVerilog interface and program learning
Complete linear regression manually based on pytoch framework
一文了解如何源码编译Rainbond基础组件
[quick start of Digital IC Verification] 10. Verilog RTL design must know FIFO
Qinglong panel -- Huahua reading
饥荒云服管理脚本
Blob object introduction
Rainbond 5.7.1 支持对接多家公有云和集群异常报警
Network learning (II) -- Introduction to socket
Use of JMeter
Dedecms collects content without writing rules
[step on the pit series] H5 cross domain problem of uniapp
【数字IC验证快速入门】11、Verilog TestBench(VTB)入门
【无标题】
eBPF Cilium实战(2) - 底层网络可观测性