GStreamer: 8路以上的osxaudiosrc输入

#include <gst/gst.h>

int main(int argc, char *argv[]) {
    GstElement *pipeline, *audiosrc, *audioconvert, *filesink;
    GstBus *bus;
    GstMessage *msg;
    GstStateChangeReturn ret;

    gst_init(&argc, &argv);

    pipeline = gst_pipeline_new("audio-pipeline");
    audiosrc = gst_element_factory_make("osxaudiosrc", "audio-source");
    audioconvert = gst_element_factory_make("audioconvert", "audio-converter");
    filesink = gst_element_factory_make("filesink", "audio-sink");

    g_object_set(G_OBJECT(audiosrc), "device", "/dev/audio0", NULL);
    g_object_set(G_OBJECT(filesink), "location", "output0.wav", NULL);

    gst_bin_add_many(GST_BIN(pipeline), audiosrc, audioconvert, filesink, NULL);
    gst_element_link_many(audiosrc, audioconvert, filesink, NULL);

    ret = gst_element_set_state(pipeline, GST_STATE_PLAYING);
    if (ret == GST_STATE_CHANGE_FAILURE) {
        g_printerr("Unable to set the pipeline to the playing state.\n");
        gst_object_unref(pipeline);
        return -1;
    }

    bus = gst_element_get_bus(pipeline);
    msg = gst_bus_timed_pop_filtered(bus, GST_CLOCK_TIME_NONE,
                                     static_cast<GstMessageType>(GST_MESSAGE_ERROR | GST_MESSAGE_EOS));

    if (msg != NULL)
        gst_message_unref(msg);

    gst_object_unref(bus);
    gst_element_set_state(pipeline, GST_STATE_NULL);
    gst_object_unref(pipeline);
    return 0;
}