Bug in GStreamer 1.0 Python Bindings (Related to: https://github.com/teltek/Galicaster/issues/29)

gst_c_version.c

/*
gcc gst_c_version.c -o gst_c_version `pkg-config --cflags --libs gstreamer-1.0 gtk+-3.0`
 */

#include <gst/gst.h>
#include <gtk/gtk.h>

typedef struct _CustomData {
  GstElement *pipeline;
  int s;
} CustomData;

static GstElement *test_gst_element_factory_make() {
  GstElement *pipeline, *bin;
  GstElement *source, *sink;

  pipeline = gst_pipeline_new ("test-pipeline");
  bin = gst_bin_new ("test-bin");

  source = gst_element_factory_make ("videotestsrc", "source");
  sink = gst_element_factory_make ("autovideosink", "sink");
  gst_bin_add_many (GST_BIN (bin), source, sink, NULL);
  gst_bin_add_many (GST_BIN (pipeline), bin, NULL);

  return pipeline;
}


static GstElement *test_gst_parse_launch() {
  GstElement *pipeline, *bin;
  GstElement *source, *sink;

  pipeline = gst_pipeline_new ("test-pipeline");
  bin = gst_parse_launch ("(audiotestsrc ! alsasink)", NULL);

  gst_bin_add_many (GST_BIN (pipeline), bin, NULL);

  return pipeline;
}

static GstElement *test_gst_parse_bin_from_description() {
  GstElement *pipeline, *bin;
  GstElement *source, *sink;
  GError *err = NULL;

  pipeline = gst_pipeline_new ("test-pipeline");
  bin = gst_parse_bin_from_description ("audiotestsrc ! alsasink", FALSE, &err);

  gst_bin_add_many (GST_BIN (pipeline), bin, NULL);

  return pipeline;
}

void record(GstElement *pipeline) {
  gst_element_set_state (pipeline, GST_STATE_PLAYING);
}

void stop(GstElement *pipeline) {
  gst_element_set_state (pipeline, GST_STATE_NULL);
}

static int loop(CustomData *data) {
  printf("Tengo %d\n", data->s);
  if (data->s == 0) {
    printf("init\n");
    data->s = 1;
    data->pipeline = test_gst_parse_bin_from_description();
    /* data->pipeline = test_gst_parse_launch(); */
    /* data->pipeline = test_gst_element_factory_make(); */
  }else if(data->s == 1) {
    printf("record\n");
    data->s = 2;
    record(data->pipeline);
  }else if(data->s == 2) {
    printf("stop\n");
    data->s = 3;
    stop(data->pipeline);
  }else if(data->s == 3) {
    printf("null\n");
    data->s = 0;
    gst_object_unref (data->pipeline);
  }
  return 1;
}

int main(int argc, char *argv[]) {
  CustomData data;
  data.s = 0;
  /* Initialize GStreamer */
  gst_init (&argc, &argv);
  printf("start\n");
  g_timeout_add_seconds (1, (GSourceFunc)loop, &data);
  gtk_main ();

  gst_object_unref(data.pipeline);
  return 0;
}

gst_element_factory_make.py

#!/usr/bin/env python
# -*- coding:utf-8 -*-
"""
TO see the bug:
$cd /proc/`pgrep python`/fd; while true; do ls  | wc -l; sleep 1; done
"""

import gi
gi.require_version('Gst', '1.0')
gi.require_version('Gtk', '3.0')
from gi.repository import Gst
from gi.repository import GObject
from gi.repository import Gtk

class Test():
    def __init__(self):
        Gst.init(None)
        # Build the pipeline
        self.pipeline = Gst.Pipeline()

        src = Gst.ElementFactory.make('audiotestsrc', None)
        sink = Gst.ElementFactory.make('alsasink', None)
        mbin = Gst.Bin()
        mbin.add(src, sink)
        self.pipeline.add(mbin)
        src.link(sink)

    def __del__(self):
        print "__del__"

    def record(self):
        self.pipeline.set_state(Gst.State.PLAYING)

    def stop(self):
        self.pipeline.set_state(Gst.State.NULL)

t = None
s = 0
def test():
    global t, s
    print "Loop:"
    if s == 0:
        print " 1.- Preview"
        s = 1
        t = Test()

    elif s == 1:
        print " 2.- Record"
        s = 2
        t.record()

    elif s == 2:
        print " 3.- Stop"
        s = 0
        t.stop()

    return True

GObject.timeout_add_seconds(1, test)
Gtk.main()

gst_parse_bin_from_description.py

#!/usr/bin/env python
# -*- coding:utf-8 -*-
"""
TO see the bug:
$cd /proc/`pgrep python`/fd; while true; do ls  | wc -l; sleep 1; done
"""

import gi
gi.require_version('Gst', '1.0')
gi.require_version('Gtk', '3.0')
from gi.repository import Gst
from gi.repository import GObject
from gi.repository import Gtk


class Test():
    def __init__(self):
        # Build the pipeline
        Gst.init(None)
        self.pipeline = Gst.Pipeline()

        aux = "audiotestsrc ! alsasink"
        self.bin = Gst.parse_bin_from_description(aux, False)
        self.pipeline.add(self.bin)

    def __del__(self):
        print "__del__"

    def record(self):
        self.pipeline.set_state(Gst.State.PLAYING)

    def stop(self):
        self.pipeline.set_state(Gst.State.NULL)

t = None
s = 0
def test():
    global t, s
    print "Loop:"
    if s == 0:
        print " 1.- Preview"
        s = 1
        t = Test()

    elif s == 1:
        print " 2.- Record"
        s = 2
        t.record()

    elif s == 2:
        print " 3.- Stop"
        s = 0
        t.stop()

    return True

GObject.timeout_add_seconds(1, test)
Gtk.main()

gst_parse_launch.py

#!/usr/bin/env python
# -*- coding:utf-8 -*-
"""
TO see the bug:
$cd /proc/`pgrep python`/fd; while true; do ls  | wc -l; sleep 1; done
"""

import gi
gi.require_version('Gst', '1.0')
gi.require_version('Gtk', '3.0')
from gi.repository import Gst
from gi.repository import GObject
from gi.repository import Gtk

class Test():
    def __init__(self):
        # Build the pipeline
        Gst.init(None)
        self.pipeline = Gst.Pipeline()

        aux = "(audiotestsrc ! alsasink)"
        self.bin = Gst.parse_launch(aux)
        self.pipeline.add(self.bin)

    def __del__(self):
        print "__del__"

    def record(self):
        self.pipeline.set_state(Gst.State.PLAYING)

    def stop(self):
        self.pipeline.set_state(Gst.State.NULL)

t = None
s = 0
def test():
    global t, s
    print "Loop:"
    if s == 0:
        print " 1.- Preview"
        s = 1
        t = Test()

    elif s == 1:
        print " 2.- Record"
        s = 2
        t.record()

    elif s == 2:
        print " 3.- Stop"
        s = 0
        t.stop()

    return True

GObject.timeout_add_seconds(1, test)
Gtk.main()