Is it possible to create an image with C++?

Question

Can you create a PNG, GIF, etc with C++ on windows?

If it's possible, how? For an example how can you make a png image just one solid color.

Just a "hello world" example would be great...

Answer 1

For PNG, try out the PNGWriter library: http://pngwriter.sourceforge.net/

Answer 2

Yes, it is possible to do so. Some libraries for image manipulation include ImageMagick/GraphicsMagick (same API), CImg, and OpenCV. OpenCV is by far the most powerful but also the most difficult to use. CImg is probably the easiest to use, and I would strongly recommend it for beginners... you basically create an instance of the CImg<pixel_type> type, fill in the pixels, and then call "save", which will automatically deduce the type and knows how to encode it based on the file extension you give it.

Answer 3

Images are just binary files and C++ can easily write binary files. Image formats include many complicated compression algorithms so doing so is not always easy.

Its generally best to use a C++ library which can handle the loading/saving of such files for you so you can worry about more important things like you'd actually like these pictures to have in them.

Imaghttp://www.imagemagick.org is a popular one used by several open source projects but there are many others.

Answer 4

When someone asks you about Hello world, just say Hello world ...

#include "opencv/cxcore.h"
#include "opencv/cv.h"
#include "opencv/highgui.h"

int _tmain(int argc, _TCHAR* argv[])
{
    cv::Mat image(480, 640, CV_8UC3);
    cv::putText(image, "Hello world", cvPoint(320, 200), 
        CV_FONT_HERSHEY_SIMPLEX, 1, cvScalar(255, 0, 0));
    cv::imwrite("output.tif", image);
    return 0;
}