RtMidi-MidiInDummy :이 클래스는 기능을 제공하지 않습니다.

Rtmidi를 사용하여 런치 패드에서 입력을 받고 싶습니다. 그러나 런치 패드 연결에도 불구하고 0 개의 포드를 사용할 수 있습니다. " MidiInDummy :이 클래스는 기능을 제공하지 않습니다. "이 문구도 있으므로 뭔가 잘못된 것 같습니다 .

출처:

//Source : http://www.music.mcgill.ca/~gary/rtmidi/index.html#probing
#define __WINDOWS_MM__
#include <iostream>
#include <cstdlib>
#include "RtMidi.h"
int main()
{
    RtMidiIn* midiin = 0;
    RtMidiOut* midiout = 0;
    // RtMidiIn constructor
    try {
        midiin = new RtMidiIn();
    }
    catch (RtMidiError& error) {
        error.printMessage();
        exit(EXIT_FAILURE);
    }
    // Check inputs.
    unsigned int nPorts = midiin->getPortCount();
    std::cout << "\nThere are " << nPorts << " MIDI input sources available.\n";
    std::string portName;
    for (unsigned int i = 0; i < nPorts; i++) {
        try {
            portName = midiin->getPortName(i);
        }
        catch (RtMidiError& error) {
            error.printMessage();
            goto cleanup;
        }
        std::cout << "  Input Port #" << i + 1 << ": " << portName << '\n';
    }
    // RtMidiOut constructor
    try {
        midiout = new RtMidiOut();
    }
    catch (RtMidiError& error) {
        error.printMessage();
        exit(EXIT_FAILURE);
    }
    // Check outputs.
    nPorts = midiout->getPortCount();
    std::cout << "\nThere are " << nPorts << " MIDI output ports available.\n";
    for (unsigned int i = 0; i < nPorts; i++) {
        try {
            portName = midiout->getPortName(i);
        }
        catch (RtMidiError& error) {
            error.printMessage();
            goto cleanup;
        }
        std::cout << "  Output Port #" << i + 1 << ": " << portName << '\n';
    }
    std::cout << '\n';
    // Clean up
cleanup:
    delete midiin;
    delete midiout;
    return 0;
}

산출:

MidiInDummy: This class provides no functionality.
There are 0 MIDI input sources available.
MidiOutDummy: This class provides no functionality.
There are 0 MIDI output ports available.

이 문제를 어떻게 해결할 수 있습니까?