(C++) OpenCvExample1

 

OpenCvExample1 is a OpenCV example how to display an image and how to convert one to greyscale.

 

• View a screenshot of this example
• Download the Qt Creator project 'CppOpenCvExample1' (zip)

 

 

 

 

 

Technical facts

 

Application type(s)

• Desktop application

Operating system(s) or programming environment(s)

• Lubuntu 12.04 (precise)

IDE(s):

• Qt Creator 2.3.0

Project type:

• GUI application

C++ standard:

• C++98

Compiler(s):

• G++ 4.6.3

Libraries used:

• OpenCV: version 2.3.1
• Qt: version 4.8.1 (32 bit)
• STL: GNU ISO C++ Library, version 4.6.3

 

 

 

 

 

Qt project file: CppOpenCvExample1.pro

 

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#------------------------------------------------- # # Project created by QtCreator 2012-07-11T13:49:58 # #------------------------------------------------- QT       += core QT       -= gui unix {    CONFIG += link_pkgconfig    PKGCONFIG += opencv } #LIBS += -lopencv TARGET = CppOpenCvExample1 CONFIG   += console CONFIG   -= app_bundle TEMPLATE = app SOURCES += main.cpp RESOURCES += \     CppOpenCvExample1.qrc

 

 

 

 

 

main.cpp

 

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#include <QFile> #include <QResource> #include <opencv2/opencv.hpp> int main() {   const std::string filename = "image.jpg";   //Create the source image if it does not exist   {     if (!QFile::exists(filename.c_str()))     {       QFile f((std::string(":/images/") + filename).c_str());       f.copy(filename.c_str());     }     assert(QFile::exists(filename.c_str()));   }   //Load the image   const cv::Mat image_original = cv::imread(filename);   assert(image_original.data);   //Create the resulting image   cv::Mat image_result;   cv::cvtColor(image_original,image_result,CV_RGB2GRAY );   cv::imwrite("R_grey.png", image_result );   //Display the original   cv::imshow("Original",image_original );   //Display the result   cv::imshow("Result", image_result );   //Wait for a key press   cv::waitKey(0); }