时光荏苒，珍惜当下

Opencv学习2：指定图像读取

发表于 更新于 分类于 Valine：

  此次图像读取学习，所有程序都是在opencv_learning功能包下编译完成的。

创建功能包opencv_learning

创建功能包

  打开终端，创建功能包opencv_learning

$ cs
$ catkin_create_pkg opencv_learning std_msgs roscpp rospy cv_bridge image_transport sensor_msgs
$ cm

添加OpenCV库

  修改功能包下CMakeLists.txt文件

CMakeLists.txt
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find_package(catkin REQUIRED COMPONENTS
+  OpenCV
  cv_bridge
  image_transport
  sensor_msgs
  std_msgs
  roscpp
  rospy
)

include_directories(
  include ${catkin_INCLUDE_DIRS}
# include
  ${catkin_INCLUDE_DIRS}
+  ${OpenCV_INCLUDE_DIRS}
)

读取指定图片

添加图片

图片路径：/home/tao/opencv/1.jpg

1.jpg

c++程序

  • 新建程序
read_image_c.cpp
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#include <ros/ros.h>
#include <opencv2/opencv.hpp>
#include <opencv2/imgproc/imgproc.hpp>
#include <opencv2/highgui/highgui.hpp>
 
int main(int argc, char** argv)
{
    //创建一个Mat对象cv_image，它将存储加载的图像的数据
    cv::Mat cv_image = cv::imread("/home/tao/opencv/1.jpg");
    if(cv_image.empty())
        {
            ROS_ERROR("Read the picture failed!");
            return -1;
        }
    //创建窗口，显示图像
    cv::namedWindow("Display Image",cv::WINDOW_NORMAL);
    cv::resizeWindow("Display Image", 640, 480);
    cv::imshow("Display Image", cv_image);
    cv::waitKey(0);
    cv::destroyAllWindows();

    return 0;
}
  • 修改功能包下CMakeLists.txt文件,添加以下内容
CMakeLists.txt
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add_executable(read_image_c
  src/read_image_c.cpp
)
add_dependencies(read_image_c ${${PROJECT_NAME}_EXPORTED_TARGETS} ${catkin_EXPORTED_TARGETS})
target_link_libraries(read_image_c
  ${catkin_LIBRARIES}
)
  • 编译运行
$ cm
$ rosrun opencv_learning read_image_c
c++程序运行结果

python程序

read_image_p.py
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#!/usr/bin/env python2
# coding:utf-8

import rospy
import cv2

def read_image():
    img = cv2.imread('/home/tao/opencv/1.jpg',cv2.IMREAD_COLOR)
    cv2.namedWindow('image',cv2.WINDOW_NORMAL)
    cv2.resizeWindow("image", 640, 480);
    cv2.imshow('image', img)
    cv2.waitKey(0)
    cv2.destroyAllWindows()
 
if __name__ == '__main__':
    read_image()
  • 添加权限并运行
$ cs
$ cd opencv_learning/src/
$ chmod +x read_image_p.py 
$ rosrun opencv_learning read_image_p.py
python程序运行结果
完
+