// This code demonstrates how to get the histogram for a 
        // previously taken 512x600 pixel CCD image that currently
        // resides in the kernel image buffer (CController::mapFd).

        #include <iostream>
        #include "CController.h"
        #include "CImage.h"

        using namespace std;
        using namespace arc;

        int main()
        {
            CController cController;

            try {
                // .... previously exposed quad readout
                // .... image resides in kernel buffer
                // .... at CController.mapFd

                CImage cImg;

                long lHistSize = 0;
                long *lHist = cImg.Histogram(  &lHistSize,
                                               cController.mapFd,
                                               512,
                                               600 );

                for ( int i=0; i<lHistSize; i++ )
                    cout << "hist[ " << i << " ]: " << lHist[ i ] << endl;
            }
            catch ( std::exception &e )
            {
                cerr << "Exception Occurred: " << e.what() << endl;
            }
        }