Gstreamer Multifilesrc循环短视频

#include <gst/gst.h>

int main(int argc, char *argv[]) {
    GstElement *pipeline, *multifilesrc, *decoder, *videoconvert, *videosink;
    GstBus *bus;
    GstMessage *msg;
    GstStateChangeReturn ret;

    /* Initialize GStreamer */
    gst_init(&argc, &argv);

    /* Create the elements */
    pipeline = gst_pipeline_new("video-player");
    multifilesrc = gst_element_factory_make("multifilesrc", "file-source");
    decoder = gst_element_factory_make("decodebin", "decoder");
    videoconvert = gst_element_factory_make("videoconvert", "converter");
    videosink = gst_element_factory_make("autovideosink", "video-output");

    if (!pipeline || !multifilesrc || !decoder || !videoconvert || !videosink) {
        g_printerr("Not all elements could be created.\n");
        return -1;
    }

    /* Set up the multifilesrc */
    g_object_set(G_OBJECT(multifilesrc), "location", "video1.mp4,video2.mp4,video3.mp4", NULL);
    g_object_set(G_OBJECT(multifilesrc), "loop", TRUE, NULL);

    /* Add elements to the pipeline */
    gst_bin_add_many(GST_BIN(pipeline), multifilesrc, decoder, videoconvert, videosink, NULL);

    /* Link the elements together */
    if (!gst_element_link_many(multifilesrc, decoder, videoconvert, videosink, NULL)) {
        g_printerr("Elements could not be linked.\n");
        gst_object_unref(pipeline);
        return -1;
    }

    /* Connect the decoder's pad-added signal */
    g_signal_connect(decoder, "pad-added", G_CALLBACK(on_pad_added), videoconvert);

    /* Start playing */
    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;
    }

    /* Wait until error or EOS */
    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));

    /* Free resources */
    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;
}

void on_pad_added(GstElement *element, GstPad *pad, gpointer data) {
    GstPad *sinkpad = gst_element_get_static_pad(GST_ELEMENT(data), "sink");
    if (gst_pad_is_linked(sinkpad)) {
        g_print("Pad already linked. Ignoring.\n");
        goto done;
    }
    if (gst_pad_link(pad, sinkpad) != GST_PAD_LINK_OK) {
        g_print("Failed to link pads.\n");
        goto done;
    }
    g_print("Pads linked.\n");
done:
    gst_object_unref(sinkpad);
}