如何在c++中用ffmpeg获取DirectShow设备列表？

#include <iostream>
extern "C" {
#include <libavformat/avformat.h>
#include <libavdevice/avdevice.h>
}

int main() {
    av_register_all();
    avdevice_register_all();
    avformat_network_init();

    AVFormatContext* formatContext = nullptr;
    if (avformat_open_input(&formatContext, "video=dshow", nullptr, nullptr) != 0) {
        std::cerr << "Failed to open device" << std::endl;
        return -1;
    }

    if (avformat_find_stream_info(formatContext, nullptr) < 0) {
        std::cerr << "Failed to find stream information" << std::endl;
        return -1;
    }

    for (unsigned int i = 0; i < formatContext->nb_streams; i++) {
        AVStream* stream = formatContext->streams[i];
        AVCodecParameters* codecParams = stream->codecpar;
        if (codecParams->codec_type == AVMEDIA_TYPE_VIDEO) {
            std::cout << "Video Device: " << codecParams->device_name << std::endl;
        }
        else if (codecParams->codec_type == AVMEDIA_TYPE_AUDIO) {
            std::cout << "Audio Device: " << codecParams->device_name << std::endl;
        }
    }

    avformat_close_input(&formatContext);
    avformat_free_context(formatContext);

    return 0;
}