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Image Processing

Monochrome (B&W Black-and-White)

$author:   Jin-Wen (Ed) Lai           
$date:     Mar. 2018
$keywords: image, processing, rgb, colormap, grayscale

An implementation of digital image processing to change RGB image or colormap to monochrome (black-and-white) image.

Content

Requirements

  • OpenCV 
    # apt-get install libopencv-dev
# apt-get install cmake

Programming

  • create Memochrome.cpp 
#include <cv.h>
#include <highgui.h>
#include <opencv2/imgproc/imgproc.hpp>
#include <stdio.h>

using namespace cv;

int main( int argc, char** argv )
{

 Mat im_rgb  = imread("../../lena.png");
 Mat im_gray;
 cvtColor(im_rgb,im_gray,CV_RGB2GRAY);
 Mat img_bw = im_gray > 128;
 imwrite("lena_monochrome.png", img_bw);
 return 0;
}

CMakeLists

  • Create CMakeLists.txt 
cmake_minimum_required(VERSION 2.8)
project( Monochrome )
find_package( OpenCV REQUIRED )
add_executable( Monochrome Monochrome.cpp )
target_link_libraries( Monochrome ${OpenCV_LIBS} )

Running

  • Issue below commands 
cmake .
make
./ Monochrome
  • Result
Original Grayscale

Note:

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Reference: