Segfault in nv3dsink when setting window handle using gst_video_overlay_set_window_handle()

Autonomous Machines Jetson & Embedded Systems Jetson Nano
1

When the gst_video_overlay_set_window_handle() function is used to set the window handle with nv3dsink it segfaults. I have patched the source code for a previous version of libgstnvvideosinks_src.tbz2 (32.4.3) to fix this bug but the current version (32.5) does not function properly when built from sources. The segfault is caused by some variables not getting initialized properly.

3

Hi merwin,

May I know which patch you’re referring to? From which topic?

4

It’s my own patch.

5

Hi,
We would need to reproduce it and do further check. Is it possible to share the patch so that we can replicate it on r32.5/Jetson Nano?

6 
--- a/gst-plugins-nv-video-sinks/nv3dsink/gstnv3dsink.c
+++ b/gst-plugins-nv-video-sinks/nv3dsink/gstnv3dsink.c
@@ -546,4 +546,7 @@ gst_nv3dsink_init (GstNv3dSink * nv3dsink)
 
   /* mutex to serialize create, set and get window handle calls */
   g_mutex_init (&nv3dsink->win_handle_lock);
+
+  /* init vars */
+  gst_nv3dsink_start (nv3dsink);
 }
--
7

Hi,
For more information, could we run the command to reproduce the issue?

$ gst-launch-1.0 videotestsrc ! nvvidconv ! 'video/x-raw(memory:NVMM),format=NV12' ! nv3dsink
8

gst-launch-1.0 can’t be used to reproduce the issue. The issue occurs when video sink’s window handle (typically obtained with XCreateWindow() ) is set with the gst_video_overlay_set_window_handle() function to override the window created internally by the video sink. It can only be done programmatically.

9

There is no update from you for a period, assuming this is not an issue any more.
Hence we are closing this topic. If need further support, please open a new one.
Thanks

Hi,
Please make a patch to this sample so that we can replicate the segment fault:

#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;

    launch_stream
    << "videotestsrc is-live=1 name=mysource ! "
    << "nvvidconv ! video/x-raw(memory:NVMM),format=NV12 ! "
    << "nv3dsink ";

    launch_string = launch_stream.str();

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

    GError *error = nullptr;
    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(10*usec);
    GstElement* src = gst_bin_get_by_name(GST_BIN(gst_pipeline), "mysource");
    gst_element_send_event (src, gst_event_new_eos ());
    // Wait for EOS message
    GstBus *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_main_loop_unref(main_loop);

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