[MOVED FROM GST-P-FARSIGHT] Added dtmfsrc, a DTMF Tone Generator, and made it part of the 'dtmf' plugin.

20070820184852-4f0f6-a0d85e67708290aebafa89ab79d3cedd5815b620.gz

6 files changed, 845 insertions, 23 deletions

diff --git a/gst/dtmf/Makefile.am b/gst/dtmf/Makefile.am
index 603b32c28..210dcadea 100644
--- a/gst/dtmf/Makefile.am
+++ b/gst/dtmf/Makefile.am
@@ -1,9 +1,13 @@
-plugin_LTLIBRARIES = libgstrtpdtmf.la
+plugin_LTLIBRARIES = libgstdtmf.la
 
-libgstrtpdtmf_la_SOURCES = gstrtpdtmfsrc.c
+libgstdtmf_la_SOURCES = gstdtmfsrc.c \
+                        gstrtpdtmfsrc.c \
+                        gstdtmf.c
 
-libgstrtpdtmf_la_CFLAGS = $(GST_CFLAGS) $(GST_PLUGINS_BASE_CFLAGS) $(ERROR_CFLAGS) -DEXTERN_BUF -DRTP_SUPPORT
-libgstrtpdtmf_la_LIBADD = $(GST_LIBS_LIBS)
-libgstrtpdtmf_la_LDFLAGS = $(GST_PLUGIN_LDFLAGS) $(GST_BASE_LIBS) $(GST_PLUGINS_BASE_LIBS) -lgstrtp-@GST_MAJORMINOR@
+noinst_HEADERS = gstdtmfsrc.h \
+                 gstrtpdtmfsrc.h
+
+libgstdtmf_la_CFLAGS = $(GST_CFLAGS) $(GST_PLUGINS_BASE_CFLAGS) $(ERROR_CFLAGS) -DEXTERN_BUF -DRTP_SUPPORT
+libgstdtmf_la_LIBADD = $(GST_LIBS_LIBS)
+libgstdtmf_la_LDFLAGS = $(GST_PLUGIN_LDFLAGS) $(GST_BASE_LIBS) $(GST_PLUGINS_BASE_LIBS) -lgstrtp-@GST_MAJORMINOR@
 
-noinst_HEADERS = gstrtpdtmfsrc.h
diff --git a/gst/dtmf/gstdtmf.c b/gst/dtmf/gstdtmf.c
new file mode 100644
index 000000000..308688574
--- /dev/null
+++ b/gst/dtmf/gstdtmf.c
@@ -0,0 +1,27 @@
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "gstdtmfsrc.h"
+#include "gstrtpdtmfsrc.h"
+
+
+static gboolean
+plugin_init (GstPlugin * plugin)
+{
+  if (!gst_dtmf_src_plugin_init (plugin))
+    return FALSE;
+
+  if (!gst_rtp_dtmf_src_plugin_init (plugin))
+    return FALSE;
+
+
+  return TRUE;
+}
+
+GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,
+    GST_VERSION_MINOR,
+    "dtmf",
+    "DTMF plugins",
+    plugin_init, "0.1" , "LGPL", "DTMF", "");
diff --git a/gst/dtmf/gstdtmfsrc.c b/gst/dtmf/gstdtmfsrc.c
new file mode 100644
index 000000000..523419db4
--- /dev/null
+++ b/gst/dtmf/gstdtmfsrc.c
@@ -0,0 +1,729 @@
+/* GStreamer DTMF source
+ *
+ * gstdtmfsrc.c:
+ *
+ * Copyright (C) <2007> Collabora.
+ *   Contact: Youness Alaoui <youness.alaoui@collabora.co.uk>
+ * Copyright (C) <2007> Nokia Corporation.
+ *   Contact: Zeeshan Ali <zeeshan.ali@nokia.com>
+ * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
+ *               2000,2005 Wim Taymans <wim@fluendo.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+/**
+ * SECTION:element-dtmfsrc
+ * @short_description: Generates DTMF packets
+ *
+ * <refsect2>
+ *
+ * <para>
+ * The DTMFSrc element generates DTMF (ITU-T Q.23 Specification) tone packets on request
+ * from application. The application communicates the beginning and end of a
+ * DTMF event using custom upstream gstreamer events. To report a DTMF event, an
+ * application must send an event of type GST_EVENT_CUSTOM_UPSTREAM, having a
+ * structure of name "dtmf-event" with fields set according to the following
+ * table:
+ * </para>
+ *
+ * <para>
+ * <informaltable>
+ * <tgroup cols='4'>
+ * <colspec colname='Name' />
+ * <colspec colname='Type' />
+ * <colspec colname='Possible values' />
+ * <colspec colname='Purpose' />
+ *
+ * <thead>
+ * <row>
+ * <entry>Name</entry>
+ * <entry>GType</entry>
+ * <entry>Possible values</entry>
+ * <entry>Purpose</entry>
+ * </row>
+ * </thead>
+ *
+ * <tbody>
+ * <row>
+ * <entry>type</entry>
+ * <entry>G_TYPE_INT</entry>
+ * <entry>0-1</entry>
+ * <entry>The application uses this field to specify which of the two methods
+ * specified in RFC 2833 to use. The value should be 0 for tones and 1 for
+ * named events. This element is only capable of generating tones.
+ * </entry>
+ * </row>
+ * <row>
+ * <entry>number</entry>
+ * <entry>G_TYPE_INT</entry>
+ * <entry>0-16</entry>
+ * <entry>The event number.</entry>
+ * </row>
+ * <row>
+ * <entry>volume</entry>
+ * <entry>G_TYPE_INT</entry>
+ * <entry>0-36</entry>
+ * <entry>This field describes the power level of the tone, expressed in dBm0
+ * after dropping the sign. Power levels range from 0 to -63 dBm0. The range of
+ * valid DTMF is from 0 to -36 dBm0. Can be omitted if start is set to FALSE.
+ * </entry>
+ * </row>
+ * <row>
+ * <entry>start</entry>
+ * <entry>G_TYPE_BOOLEAN</entry>
+ * <entry>True or False</entry>
+ * <entry>Whether the event is starting or ending.</entry>
+ * </row>
+ * <row>
+ * <entry>method</entry>
+ * <entry>G_TYPE_INT</entry>
+ * <entry>1</entry>
+ * <entry>The method used for sending event, this element will react if this field
+ * is absent or 2.
+ * </entry>
+ * </row>
+ * </tbody>
+ * </tgroup>
+ * </informaltable>
+ * </para>
+ *
+ * <para>For example, the following code informs the pipeline (and in turn, the
+ * DTMFSrc element inside the pipeline) about the start of a DTMF named
+ * event '1' of volume -25 dBm0:
+ * </para>
+ *
+ * <para>
+ * <programlisting>
+ * structure = gst_structure_new ("dtmf-event",
+ *                    "type", G_TYPE_INT, 0,
+ *                    "number", G_TYPE_INT, 1,
+ *                    "volume", G_TYPE_INT, 25,
+ *                    "start", G_TYPE_BOOLEAN, TRUE, NULL);
+ *
+ * event = gst_event_new_custom (GST_EVENT_CUSTOM_UPSTREAM, structure);
+ * gst_element_send_event (pipeline, event);
+ * </programlisting>
+ * </para>
+ *
+ * </refsect2>
+ */
+
+#ifdef HAVE_CONFIG_H
+#  include "config.h"
+#endif
+
+#include <stdlib.h>
+#include <string.h>
+#include <math.h>
+
+#ifndef M_PI
+# define M_PI           3.14159265358979323846  /* pi */
+#endif
+
+
+#include "gstdtmfsrc.h"
+
+#define GST_TONE_DTMF_TYPE_EVENT 0
+#define DEFAULT_PACKET_INTERVAL  50 /* ms */
+#define MIN_PACKET_INTERVAL      10 /* ms */
+#define MAX_PACKET_INTERVAL      50 /* ms */
+#define SAMPLE_RATE              8000
+#define SAMPLE_SIZE              16
+#define CHANNELS                 1
+#define MIN_EVENT                0
+#define MAX_EVENT                16
+#define MIN_VOLUME               0
+#define MAX_VOLUME               36
+
+
+
+typedef struct st_dtmf_key {
+        char *event_name;
+        int event_encoding;
+        float low_frequency;
+        float high_frequency;
+} DTMF_KEY;
+
+static const DTMF_KEY DTMF_KEYS[] = {
+        {"DTMF_KEY_EVENT_0",  0, 941, 1336},
+        {"DTMF_KEY_EVENT_1",  1, 697, 1209},
+        {"DTMF_KEY_EVENT_2",  2, 697, 1336},
+        {"DTMF_KEY_EVENT_3",  3, 697, 1477},
+        {"DTMF_KEY_EVENT_4",  4, 770, 1209},
+        {"DTMF_KEY_EVENT_5",  5, 770, 1336},
+        {"DTMF_KEY_EVENT_6",  6, 770, 1477},
+        {"DTMF_KEY_EVENT_7",  7, 852, 1209},
+        {"DTMF_KEY_EVENT_8",  8, 852, 1336},
+        {"DTMF_KEY_EVENT_9",  9, 852, 1477},
+        {"DTMF_KEY_EVENT_S", 10, 941, 1209},
+        {"DTMF_KEY_EVENT_P", 11, 941, 1477},
+        {"DTMF_KEY_EVENT_A", 12, 697, 1633},
+        {"DTMF_KEY_EVENT_B", 13, 770, 1633},
+        {"DTMF_KEY_EVENT_C", 14, 852, 1633},
+        {"DTMF_KEY_EVENT_D", 15, 941, 1633},
+};
+
+#define MAX_DTMF_EVENTS 16
+
+enum {
+DTMF_KEY_EVENT_1 = 1,
+DTMF_KEY_EVENT_2 = 2,
+DTMF_KEY_EVENT_3 = 3,
+DTMF_KEY_EVENT_4 = 4,
+DTMF_KEY_EVENT_5 = 5,
+DTMF_KEY_EVENT_6 = 6,
+DTMF_KEY_EVENT_7 = 7,
+DTMF_KEY_EVENT_8 = 8,
+DTMF_KEY_EVENT_9 = 9,
+DTMF_KEY_EVENT_0 = 0,
+DTMF_KEY_EVENT_STAR = 10,
+DTMF_KEY_EVENT_POUND = 11,
+DTMF_KEY_EVENT_A = 12,
+DTMF_KEY_EVENT_B = 13,
+DTMF_KEY_EVENT_C = 14,
+DTMF_KEY_EVENT_D = 15,
+};
+
+/* elementfactory information */
+static const GstElementDetails gst_dtmf_src_details =
+GST_ELEMENT_DETAILS ("DTMF tone generator",
+    "Source/Audio",
+    "Generates DTMF tones",
+    "Youness Alaoui <youness.alaoui@collabora.co.uk>");
+
+GST_DEBUG_CATEGORY_STATIC (gst_dtmf_src_debug);
+#define GST_CAT_DEFAULT gst_dtmf_src_debug
+
+enum
+{
+  PROP_0,
+  PROP_INTERVAL,
+};
+
+static GstStaticPadTemplate gst_dtmf_src_template =
+GST_STATIC_PAD_TEMPLATE ("src",
+    GST_PAD_SRC,
+    GST_PAD_ALWAYS,
+    GST_STATIC_CAPS ("audio/x-raw-int, "
+        "width = (int) 16, "
+        "depth = (int) 16, "
+	"endianness = (int) 1234, "
+	"signed = (bool) true, "
+        "rate = (int) 8000, "
+	"channels = (int) 1")
+    );
+
+static GstElementClass *parent_class = NULL;
+
+static void gst_dtmf_src_base_init (gpointer g_class);
+static void gst_dtmf_src_class_init (GstDTMFSrcClass * klass);
+static void gst_dtmf_src_init (GstDTMFSrc * dtmfsrc, gpointer g_class);
+static void gst_dtmf_src_finalize (GObject * object);
+
+GType
+gst_dtmf_src_get_type (void)
+{
+  static GType base_src_type = 0;
+
+  if (G_UNLIKELY (base_src_type == 0)) {
+    static const GTypeInfo base_src_info = {
+      sizeof (GstDTMFSrcClass),
+      (GBaseInitFunc) gst_dtmf_src_base_init,
+      NULL,
+      (GClassInitFunc) gst_dtmf_src_class_init,
+      NULL,
+      NULL,
+      sizeof (GstDTMFSrc),
+      0,
+      (GInstanceInitFunc) gst_dtmf_src_init,
+    };
+
+    base_src_type = g_type_register_static (GST_TYPE_ELEMENT,
+        "GstDTMFSrc", &base_src_info, 0);
+  }
+  return base_src_type;
+}
+
+static void gst_dtmf_src_set_property (GObject * object, guint prop_id,
+    const GValue * value, GParamSpec * pspec);
+static void gst_dtmf_src_get_property (GObject * object, guint prop_id,
+    GValue * value, GParamSpec * pspec);
+static gboolean gst_dtmf_src_handle_event (GstPad * pad, GstEvent * event);
+static GstStateChangeReturn gst_dtmf_src_change_state (GstElement * element,
+    GstStateChange transition);
+static void gst_dtmf_src_generate_tone(GstDTMFSrc *dtmfsrc, DTMF_KEY key, float duration,
+    GstBuffer * buffer);
+static void gst_dtmf_src_push_next_tone_packet (GstDTMFSrc *dtmfsrc);
+static void gst_dtmf_src_start (GstDTMFSrc *dtmfsrc, gint event_number,
+    gint event_volume);
+static void gst_dtmf_src_stop (GstDTMFSrc *dtmfsrc);
+
+static void
+gst_dtmf_src_base_init (gpointer g_class)
+{
+  GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);
+
+  GST_DEBUG_CATEGORY_INIT (gst_dtmf_src_debug,
+          "dtmfsrc", 0, "dtmfsrc element");
+
+  gst_element_class_add_pad_template (element_class,
+      gst_static_pad_template_get (&gst_dtmf_src_template));
+
+  gst_element_class_set_details (element_class, &gst_dtmf_src_details);
+}
+
+static void
+gst_dtmf_src_class_init (GstDTMFSrcClass * klass)
+{
+  GObjectClass *gobject_class;
+  GstElementClass *gstelement_class;
+
+  gobject_class = G_OBJECT_CLASS (klass);
+  gstelement_class = GST_ELEMENT_CLASS (klass);
+
+  parent_class = g_type_class_peek_parent (klass);
+
+  gobject_class->finalize = GST_DEBUG_FUNCPTR (gst_dtmf_src_finalize);
+  gobject_class->set_property =
+      GST_DEBUG_FUNCPTR (gst_dtmf_src_set_property);
+  gobject_class->get_property =
+      GST_DEBUG_FUNCPTR (gst_dtmf_src_get_property);
+
+  g_object_class_install_property (G_OBJECT_CLASS (klass), PROP_INTERVAL,
+      g_param_spec_int ("interval", "Interval between tone packets",
+          "Interval in ms between two tone packets", MIN_PACKET_INTERVAL,
+          MAX_PACKET_INTERVAL, DEFAULT_PACKET_INTERVAL, G_PARAM_READWRITE));
+
+  gstelement_class->change_state =
+      GST_DEBUG_FUNCPTR (gst_dtmf_src_change_state);
+}
+
+static void
+gst_dtmf_src_init (GstDTMFSrc * dtmfsrc, gpointer g_class)
+{
+  dtmfsrc->srcpad =
+      gst_pad_new_from_static_template (&gst_dtmf_src_template, "src");
+  GST_DEBUG_OBJECT (dtmfsrc, "adding src pad");
+  gst_element_add_pad (GST_ELEMENT (dtmfsrc), dtmfsrc->srcpad);
+
+  gst_pad_set_event_function (dtmfsrc->srcpad, gst_dtmf_src_handle_event);
+
+  dtmfsrc->interval = DEFAULT_PACKET_INTERVAL;
+
+  dtmfsrc->sample = 0;
+
+  GST_DEBUG_OBJECT (dtmfsrc, "init done");
+}
+
+static void
+gst_dtmf_src_finalize (GObject * object)
+{
+  GstDTMFSrc *dtmfsrc;
+
+  dtmfsrc = GST_DTMF_SRC (object);
+
+  G_OBJECT_CLASS (parent_class)->finalize (object);
+}
+
+static gboolean
+gst_dtmf_src_handle_dtmf_event (GstDTMFSrc *dtmfsrc,
+        const GstStructure * event_structure)
+{
+  gint event_type;
+  gboolean start;
+  gint method;
+
+  if (!gst_structure_get_int (event_structure, "type", &event_type) ||
+      !gst_structure_get_boolean (event_structure, "start", &start) ||
+      (start == TRUE && event_type != GST_TONE_DTMF_TYPE_EVENT))
+    goto failure;
+
+  if (gst_structure_get_int (event_structure, "method", &method)) {
+    if (method != 2) {
+      goto failure;
+    }
+  }
+
+  if (start) {
+    gint event_number;
+    gint event_volume;
+
+    if (!gst_structure_get_int (event_structure, "number", &event_number) ||
+            !gst_structure_get_int (event_structure, "volume", &event_volume))
+      goto failure;
+
+    GST_DEBUG_OBJECT (dtmfsrc, "Received start event %d with volume %d",
+            event_number, event_volume);
+    gst_dtmf_src_start (dtmfsrc, event_number, event_volume);
+  }
+
+  else {
+    GST_DEBUG_OBJECT (dtmfsrc, "Received stop event");
+    gst_dtmf_src_stop (dtmfsrc);
+  }
+
+  return TRUE;
+failure:
+  return FALSE;
+}
+
+static gboolean
+gst_dtmf_src_handle_custom_upstream (GstDTMFSrc *dtmfsrc,
+    GstEvent * event)
+{
+  gboolean result = FALSE;
+  const GstStructure *structure;
+
+  if (GST_STATE (dtmfsrc) != GST_STATE_PLAYING) {
+    GST_DEBUG_OBJECT (dtmfsrc, "Received event while not in PLAYING state");
+    goto ret;
+  }
+
+  GST_DEBUG_OBJECT (dtmfsrc, "Received event is of our interest");
+  structure = gst_event_get_structure (event);
+  if (structure && gst_structure_has_name (structure, "dtmf-event"))
+    result = gst_dtmf_src_handle_dtmf_event (dtmfsrc, structure);
+
+ret:
+  return result;
+}
+
+static gboolean
+gst_dtmf_src_handle_event (GstPad * pad, GstEvent * event)
+{
+  GstDTMFSrc *dtmfsrc;
+  gboolean result = FALSE;
+
+  dtmfsrc = GST_DTMF_SRC (GST_PAD_PARENT (pad));
+
+  GST_DEBUG_OBJECT (dtmfsrc, "Received an event on the src pad");
+  switch (GST_EVENT_TYPE (event)) {
+    case GST_EVENT_CUSTOM_UPSTREAM:
+    {
+      result = gst_dtmf_src_handle_custom_upstream (dtmfsrc, event);
+      break;
+    }
+    /* Ideally this element should not be flushed but let's handle the event
+     * just in case it is */
+    case GST_EVENT_FLUSH_START:
+      gst_dtmf_src_stop (dtmfsrc);
+      result = TRUE;
+      break;
+    case GST_EVENT_FLUSH_STOP:
+      gst_segment_init (&dtmfsrc->segment, GST_FORMAT_UNDEFINED);
+      break;
+    case GST_EVENT_NEWSEGMENT:
+      {
+        gboolean update;
+        gdouble rate;
+        GstFormat fmt;
+        gint64 start, stop, position;
+
+        gst_event_parse_new_segment (event, &update, &rate, &fmt, &start,
+            &stop, &position);
+        gst_segment_set_newsegment (&dtmfsrc->segment, update, rate, fmt,
+            start, stop, position);
+      }
+      /* fallthrough */
+    default:
+      result = gst_pad_event_default (pad, event);
+      break;
+  }
+
+  gst_event_unref (event);
+  return result;
+}
+
+static void
+gst_dtmf_src_set_property (GObject * object, guint prop_id,
+    const GValue * value, GParamSpec * pspec)
+{
+  GstDTMFSrc *dtmfsrc;
+
+  dtmfsrc = GST_DTMF_SRC (object);
+
+  switch (prop_id) {
+    case PROP_INTERVAL:
+      dtmfsrc->interval = g_value_get_int (value);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
+}
+
+static void
+gst_dtmf_src_get_property (GObject * object, guint prop_id, GValue * value,
+    GParamSpec * pspec)
+{
+  GstDTMFSrc *dtmfsrc;
+
+  dtmfsrc = GST_DTMF_SRC (object);
+
+  switch (prop_id) {
+    case PROP_INTERVAL:
+      g_value_set_uint (value, dtmfsrc->interval);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
+}
+
+static void
+gst_dtmf_src_set_stream_lock (GstDTMFSrc *dtmfsrc, gboolean lock)
+{
+   GstEvent *event;
+   GstStructure *structure;
+
+   structure = gst_structure_new ("stream-lock",
+                      "lock", G_TYPE_BOOLEAN, lock, NULL);
+
+   event = gst_event_new_custom (GST_EVENT_CUSTOM_DOWNSTREAM_OOB, structure);
+   gst_pad_push_event (dtmfsrc->srcpad, event);
+}
+
+static void
+gst_dtmf_prepare_timestamps (GstDTMFSrc *dtmfsrc)
+{
+  GstClock *clock;
+
+  clock = GST_ELEMENT_CLOCK (dtmfsrc);
+  if (clock != NULL)
+    dtmfsrc->timestamp = gst_clock_get_time (GST_ELEMENT_CLOCK (dtmfsrc));
+
+  else {
+    GST_ERROR_OBJECT (dtmfsrc, "No clock set for element %s",
+        GST_ELEMENT_NAME (dtmfsrc));
+    dtmfsrc->timestamp = GST_CLOCK_TIME_NONE;
+  }
+}
+
+static void
+gst_dtmf_src_start (GstDTMFSrc *dtmfsrc,
+        gint event_number, gint event_volume)
+{
+  GstCaps * caps = gst_pad_get_pad_template_caps (dtmfsrc->srcpad);
+
+  dtmfsrc->event = CLAMP (event_number, MIN_EVENT, MAX_EVENT);
+  dtmfsrc->volume = CLAMP (event_volume, MIN_VOLUME, MAX_VOLUME);
+
+  gst_dtmf_prepare_timestamps (dtmfsrc);
+
+  /* Don't forget to get exclusive access to the stream */
+  gst_dtmf_src_set_stream_lock (dtmfsrc, TRUE);
+
+  if (!gst_pad_set_caps (dtmfsrc->srcpad, caps))
+    GST_ERROR_OBJECT (dtmfsrc,
+            "Failed to set caps %" GST_PTR_FORMAT " on src pad", caps);
+  else
+    GST_DEBUG_OBJECT (dtmfsrc,
+            "caps %" GST_PTR_FORMAT " set on src pad", caps);
+
+
+  if (!gst_pad_start_task (dtmfsrc->srcpad,
+      (GstTaskFunction) gst_dtmf_src_push_next_tone_packet, dtmfsrc)) {
+    GST_ERROR_OBJECT (dtmfsrc, "Failed to start task on src pad");
+  }
+}
+
+static void
+gst_dtmf_src_stop (GstDTMFSrc *dtmfsrc)
+{
+  /* Don't forget to release the stream lock */
+  gst_dtmf_src_set_stream_lock (dtmfsrc, FALSE);
+
+  if (!gst_pad_pause_task (dtmfsrc->srcpad)) {
+    GST_ERROR_OBJECT (dtmfsrc, "Failed to pause task on src pad");
+    return;
+  }
+
+}
+
+static void
+gst_dtmf_src_generate_tone(GstDTMFSrc *dtmfsrc, DTMF_KEY key, float duration, GstBuffer * buffer)
+{
+  gint16 *p;
+  gint tone_size;
+  double i = 0;
+  double amplitude, f1, f2;
+
+  /* Create a buffer for the tone */
+  tone_size = ((duration/1000)*SAMPLE_RATE*SAMPLE_SIZE*CHANNELS)/8;
+  GST_BUFFER_SIZE (buffer) = tone_size;
+  GST_BUFFER_MALLOCDATA (buffer) = g_malloc(tone_size);
+  GST_BUFFER_DATA (buffer) = GST_BUFFER_MALLOCDATA (buffer);
+
+  p = (gint16 *) GST_BUFFER_MALLOCDATA (buffer);
+
+  /*
+   * For each sample point we calculate 'x' as the
+   * the amplitude value.
+   */
+  for (i = 0; i < (tone_size / (SAMPLE_SIZE/8)); i++) {
+    /*
+     * We add the fundamental frequencies together.
+     */
+    f1 = sin(2 * M_PI * key.low_frequency * (dtmfsrc->sample / SAMPLE_RATE));
+    f2 = sin(2 * M_PI * key.high_frequency * (dtmfsrc->sample / SAMPLE_RATE));
+
+    amplitude = (f1 + f2) / 2;
+
+    /* Make the [-1:1] interval into a [-32767:32767] interval */
+    amplitude *= 32767;
+
+    /* Store it in the data buffer */
+    *(p++) = (gint16) amplitude;
+
+    (dtmfsrc->sample)++;
+  }
+}
+
+static void
+gst_dtmf_src_wait_for_buffer_ts (GstDTMFSrc *dtmfsrc, GstBuffer * buf)
+{
+  GstClock *clock;
+
+  clock = GST_ELEMENT_CLOCK (dtmfsrc);
+  if (clock != NULL) {
+    GstClockID clock_id;
+    GstClockReturn clock_ret;
+
+    clock_id = gst_clock_new_single_shot_id (clock, GST_BUFFER_TIMESTAMP (buf));
+    clock_ret = gst_clock_id_wait (clock_id, NULL);
+    if (clock_ret != GST_CLOCK_OK && clock_ret != GST_CLOCK_EARLY) {
+      GST_ERROR_OBJECT (dtmfsrc, "Failed to wait on clock %s",
+              GST_ELEMENT_NAME (clock));
+    }
+    gst_clock_id_unref (clock_id);
+  }
+
+  else {
+    GST_ERROR_OBJECT (dtmfsrc, "No clock set for element %s",
+        GST_ELEMENT_NAME (dtmfsrc));
+  }
+}
+
+
+static GstBuffer *
+gst_dtmf_src_create_next_tone_packet (GstDTMFSrc *dtmfsrc)
+{
+  GstBuffer *buf = NULL;
+
+
+  GST_DEBUG_OBJECT (dtmfsrc,
+      "Creating buffer for tone");
+
+  /* create buffer to hold the tone */
+  buf = gst_buffer_new ();
+
+  /* Generate the tone */
+  gst_dtmf_src_generate_tone(dtmfsrc, DTMF_KEYS[dtmfsrc->event], dtmfsrc->interval, buf);
+
+
+  /* timestamp and duration of GstBuffer */
+  GST_BUFFER_DURATION (buf) = dtmfsrc->interval * GST_MSECOND;
+  GST_BUFFER_TIMESTAMP (buf) = dtmfsrc->timestamp;
+  dtmfsrc->timestamp += GST_BUFFER_DURATION (buf) /2;
+
+  /* FIXME: Should we sync to clock ourselves or leave it to sink */
+  gst_dtmf_src_wait_for_buffer_ts (dtmfsrc, buf);
+
+  /* Set caps on the buffer before pushing it */
+  gst_buffer_set_caps (buf, GST_PAD_CAPS (dtmfsrc->srcpad));
+
+  return buf;
+}
+
+static void
+gst_dtmf_src_push_next_tone_packet (GstDTMFSrc *dtmfsrc)
+{
+  GstBuffer *buf = NULL;
+  GstFlowReturn ret;
+
+  buf = gst_dtmf_src_create_next_tone_packet (dtmfsrc);
+
+  gst_buffer_ref(buf);
+
+  GST_DEBUG_OBJECT (dtmfsrc,
+      "pushing buffer on src pad of size %d", GST_BUFFER_SIZE (buf));
+  ret = gst_pad_push (dtmfsrc->srcpad, buf);
+  if (ret != GST_FLOW_OK) {
+    GST_ERROR_OBJECT (dtmfsrc, "Failed to push buffer on src pad", GST_BUFFER_SIZE (buf));
+  }
+
+  gst_buffer_unref(buf);
+  GST_DEBUG_OBJECT (dtmfsrc, "pushed DTMF tone on src pad");
+
+}
+
+static GstStateChangeReturn
+gst_dtmf_src_change_state (GstElement * element, GstStateChange transition)
+{
+  GstDTMFSrc *dtmfsrc;
+  GstStateChangeReturn result;
+  gboolean no_preroll = FALSE;
+
+  dtmfsrc = GST_DTMF_SRC (element);
+
+  switch (transition) {
+    case GST_STATE_CHANGE_READY_TO_PAUSED:
+      gst_segment_init (&dtmfsrc->segment, GST_FORMAT_UNDEFINED);
+      /* Indicate that we don't do PRE_ROLL */
+      no_preroll = TRUE;
+      break;
+    case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
+      /* gst_dtmf_src_start (dtmfsrc, 6, 30); */
+      break;
+    default:
+      break;
+  }
+
+  if ((result =
+          GST_ELEMENT_CLASS (parent_class)->change_state (element,
+              transition)) == GST_STATE_CHANGE_FAILURE)
+    goto failure;
+
+  switch (transition) {
+    case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
+      /* Indicate that we don't do PRE_ROLL */
+      /* gst_dtmf_src_stop (dtmfsrc); */
+      no_preroll = TRUE;
+      break;
+    default:
+      break;
+  }
+
+  if (no_preroll && result == GST_STATE_CHANGE_SUCCESS)
+    result = GST_STATE_CHANGE_NO_PREROLL;
+
+  return result;
+
+  /* ERRORS */
+failure:
+  {
+    GST_ERROR_OBJECT (dtmfsrc, "parent failed state change");
+    return result;
+  }
+}
+
+gboolean
+gst_dtmf_src_plugin_init (GstPlugin * plugin)
+{
+  return gst_element_register (plugin, "dtmfsrc",
+      GST_RANK_NONE, GST_TYPE_DTMF_SRC);
+}
diff --git a/gst/dtmf/gstdtmfsrc.h b/gst/dtmf/gstdtmfsrc.h
new file mode 100644
index 000000000..234120e96
--- /dev/null
+++ b/gst/dtmf/gstdtmfsrc.h
@@ -0,0 +1,74 @@
+/* GStreamer DTMF source
+ *
+ * gstdtmfsrc.h:
+ *
+ * Copyright (C) <2007> Collabora.
+ *   Contact: Youness Alaoui <youness.alaoui@collabora.co.uk>
+ * Copyright (C) <2007> Nokia Corporation.
+ *   Contact: Zeeshan Ali <zeeshan.ali@nokia.com>
+ * Copyright (C) <2005> Wim Taymans <wim@fluendo.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#ifndef __GST_DTMF_SRC_H__
+#define __GST_DTMF_SRC_H__
+
+#include <gst/gst.h>
+#include <gst/gstbuffer.h>
+
+G_BEGIN_DECLS
+
+#define GST_TYPE_DTMF_SRC		(gst_dtmf_src_get_type())
+#define GST_DTMF_SRC(obj)		(G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_DTMF_SRC,GstDTMFSrc))
+#define GST_DTMF_SRC_CLASS(klass)	(G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_DTMF_SRC,GstDTMFSrcClass))
+#define GST_DTMF_SRC_GET_CLASS(obj)     (G_TYPE_INSTANCE_GET_CLASS ((obj), GST_TYPE_DTMF_SRC, GstDTMFSrcClass))
+#define GST_IS_DTMF_SRC(obj)		(G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_DTMF_SRC))
+#define GST_IS_DTMF_SRC_CLASS(klass)	(G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_DTMF_SRC))
+#define GST_DTMF_SRC_CAST(obj)		((GstDTMFSrc *)(obj))
+
+typedef struct _GstDTMFSrc GstDTMFSrc;
+typedef struct _GstDTMFSrcClass GstDTMFSrcClass;
+
+/**
+ * GstDTMFSrc:
+ * @element: the parent element.
+ *
+ * The opaque #GstDTMFSrc data structure.
+ */
+struct _GstDTMFSrc {
+  GstElement        element;
+  GstPad	    *srcpad;
+  GstClockTime      timestamp;
+  GstSegment        segment;
+  double            sample;
+
+  guint16	    event;
+  guint16	    volume;
+  guint16	    interval;
+};
+
+struct _GstDTMFSrcClass {
+  GstElementClass parent_class;
+};
+
+GType gst_dtmf_src_get_type (void);
+
+gboolean gst_dtmf_src_plugin_init (GstPlugin * plugin);
+
+G_END_DECLS
+
+#endif /* __GST_DTMF_SRC_H__ */
diff --git a/gst/dtmf/gstrtpdtmfsrc.c b/gst/dtmf/gstrtpdtmfsrc.c
index 8e4f31b54..11bff7868 100644
--- a/gst/dtmf/gstrtpdtmfsrc.c
+++ b/gst/dtmf/gstrtpdtmfsrc.c
@@ -244,7 +244,7 @@ gst_rtp_dtmf_src_base_init (gpointer g_class)
   GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);
   
   GST_DEBUG_CATEGORY_INIT (gst_rtp_dtmf_src_debug,
-          "dtmfsrc", 0, "dtmfsrc element");
+          "rtpdtmfsrc", 0, "rtpdtmfsrc element");
   
   gst_element_class_add_pad_template (element_class,
       gst_static_pad_template_get (&gst_rtp_dtmf_src_template));
@@ -849,24 +849,9 @@ failure:
   }
 }
 
-static gboolean
+gboolean
 gst_rtp_dtmf_src_plugin_init (GstPlugin * plugin)
 {
   return gst_element_register (plugin, "rtpdtmfsrc",
       GST_RANK_NONE, GST_TYPE_RTP_DTMF_SRC);
 }
-
-static gboolean
-plugin_init (GstPlugin * plugin)
-{
-  if (!gst_rtp_dtmf_src_plugin_init (plugin))
-    return FALSE;
-
-  return TRUE;
-}
-
-GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,
-    GST_VERSION_MINOR,
-    "dtmf",
-    "DTMF plugins",
-    plugin_init, "0.1" , "LGPL", "DTMF", "");
diff --git a/gst/dtmf/gstrtpdtmfsrc.h b/gst/dtmf/gstrtpdtmfsrc.h
index 797526ea9..8a763cce0 100644
--- a/gst/dtmf/gstrtpdtmfsrc.h
+++ b/gst/dtmf/gstrtpdtmfsrc.h
@@ -96,6 +96,9 @@ struct _GstRTPDTMFSrcClass {
 
 GType gst_rtp_dtmf_src_get_type (void);
 
+gboolean gst_rtp_dtmf_src_plugin_init (GstPlugin * plugin);
+
+
 G_END_DECLS
 
 #endif /* __GST_RTP_DTMF_SRC_H__ */