Having issues using CImg to colormap a grey-scale Image

Question

I am using CImg for a few different things in a project and have a grey-scale image that I need to apply a jet_LUT256 color map to. I am not sure if I am on the right path or not. Any guidance would be appreciated.

#include "CImg.h"

using namespace std;
using namespace cimg_library;

int main()
{
    CImg<uint8_t> image("test.jpg");

    // Color mapping using: jet_LUT256

    image.map(jet_LUT256());

    CImgDisplay main_disp(image, "Thank you!");
    while (!main_disp.is_closed())
    {
        main_disp.wait();
    }

    return 0;
}

score 1 · Accepted Answer · answered Jul 31 '17 at 19:22

I think it needs to look more like this:

#include "CImg.h"

using namespace std;
using namespace cimg_library;

int main()
{
    CImg<unsigned char> image("test.jpg");

    // Color mapping using: jet_LUT256

    image.map(CImg<>::jet_LUT256());

    CImgDisplay main_disp(image, "Thank you!");
    while (!main_disp.is_closed())
    {
        main_disp.wait();
    }

    return 0;
}

If you make a grey gradient with ImageMagick like this:

convert -size 256x256 gradient: test.jpg

and run the program you get:

Thank you very much! That is exactly what I was looking for! — Logan Fawcett, Jul 31 '17 at 19:38

Having issues using CImg to colormap a grey-scale Image

1 Answers1