Camera liveview cannot show up again after repeated open/close the liveview for several times

[DaneLLL]

Hi,
Please check this sample:

#include <cstdlib>
#include <cstring>
#include <sstream>
#include <gst/gst.h>

using namespace std;

#define USE(x) ((void)(x))

static GstPipeline *gst_pipeline = nullptr;
static string launch_string;

GstClockTime usec = 1000000;

int main(int argc, char** argv) {
    USE(argc);
    USE(argv);

    gst_init (&argc, &argv);

    GMainLoop *main_loop;
    main_loop = g_main_loop_new (NULL, FALSE);
    ostringstream launch_stream;
    GstBus* bus;

    launch_stream
    << "videotestsrc is-live=1 ! "
    << "video/x-raw,width=1920,height=1080,format=YUY2 ! "
    << "nvvidconv ! video/x-raw(memory:NVMM),format=NV12 ! nvdrmvideosink ";

    launch_string = launch_stream.str();

    g_print("Using launch string: %s\n", launch_string.c_str());

    GError *error = nullptr;
for(guint i=0; i<300; i++) {
    g_print("loop= %d \n", i);
    gst_pipeline  = (GstPipeline*) gst_parse_launch(launch_string.c_str(), &error);

    if (gst_pipeline == nullptr) {
        g_print( "Failed to parse launch: %s\n", error->message);
        return -1;
    }
    if(error) g_error_free(error);

    gst_element_set_state((GstElement*)gst_pipeline, GST_STATE_PLAYING); 
    g_usleep(5*usec);
    gst_element_send_event ((GstElement*)gst_pipeline, gst_event_new_eos ());
    // Wait for EOS message
    bus = gst_pipeline_get_bus(GST_PIPELINE(gst_pipeline));
    gst_bus_poll(bus, GST_MESSAGE_EOS, GST_CLOCK_TIME_NONE);
    gst_element_set_state((GstElement*)gst_pipeline, GST_STATE_NULL);

    gst_object_unref(GST_OBJECT(gst_pipeline));
    g_usleep(1*usec);
}
    g_main_loop_unref(main_loop);

    g_print("going to exit \n");
    return 0;
}