3 * Copyright (C) 2008 Collabora Limited
4 * Copyright (C) 2008 Nokia Corporation
5 * Contact: Youness Alaoui <youness.alaoui@collabora.co.uk>
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Library General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Library General Public License for more details.
17 * You should have received a copy of the GNU Library General Public
18 * License along with this library; if not, write to the
19 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
20 * Boston, MA 02111-1307, USA.
23 * SECTION:element-rtpdtmfdepay
24 * @see_also: rtpdtmfsrc, rtpdtmfmux
26 * This element takes RTP DTMF packets and produces sound. It also emits a
27 * message on the #GstBus.
29 * The message is called "dtmf-event" and has the following fields
32 * <colspec colname='Name' />
33 * <colspec colname='Type' />
34 * <colspec colname='Possible values' />
35 * <colspec colname='Purpose' />
39 * <entry>GType</entry>
40 * <entry>Possible values</entry>
41 * <entry>Purpose</entry>
47 * <entry>G_TYPE_INT</entry>
49 * <entry>Which of the two methods
50 * specified in RFC 2833 to use. The value should be 0 for tones and 1 for
51 * named events. Tones are specified by their frequencies and events are specied
52 * by their number. This element currently only recognizes events.
53 * Do not confuse with "method" which specified the output.
57 * <entry>number</entry>
58 * <entry>G_TYPE_INT</entry>
60 * <entry>The event number.</entry>
63 * <entry>volume</entry>
64 * <entry>G_TYPE_INT</entry>
66 * <entry>This field describes the power level of the tone, expressed in dBm0
67 * after dropping the sign. Power levels range from 0 to -63 dBm0. The range of
68 * valid DTMF is from 0 to -36 dBm0.
72 * <entry>method</entry>
73 * <entry>G_TYPE_INT</entry>
75 * <entry>This field will always been 1 (ie RTP event) from this element.
90 #include <gst/rtp/gstrtpbuffer.h>
91 #include "gstrtpdtmfdepay.h"
94 # define M_PI 3.14159265358979323846 /* pi */
98 #define DEFAULT_PACKET_INTERVAL 50 /* ms */
99 #define MIN_PACKET_INTERVAL 10 /* ms */
100 #define MAX_PACKET_INTERVAL 50 /* ms */
101 #define SAMPLE_RATE 8000
102 #define SAMPLE_SIZE 16
107 #define MAX_VOLUME 36
108 #define MIN_INTER_DIGIT_INTERVAL 100
109 #define MIN_PULSE_DURATION 250
110 #define MIN_DUTY_CYCLE (MIN_INTER_DIGIT_INTERVAL + MIN_PULSE_DURATION)
112 #define MIN_UNIT_TIME 0
113 #define MAX_UNIT_TIME 1000
114 #define DEFAULT_UNIT_TIME 0
116 #define DEFAULT_MAX_DURATION 0
118 typedef struct st_dtmf_key
123 float high_frequency;
126 static const DTMF_KEY DTMF_KEYS[] = {
127 {"DTMF_KEY_EVENT_0", 0, 941, 1336},
128 {"DTMF_KEY_EVENT_1", 1, 697, 1209},
129 {"DTMF_KEY_EVENT_2", 2, 697, 1336},
130 {"DTMF_KEY_EVENT_3", 3, 697, 1477},
131 {"DTMF_KEY_EVENT_4", 4, 770, 1209},
132 {"DTMF_KEY_EVENT_5", 5, 770, 1336},
133 {"DTMF_KEY_EVENT_6", 6, 770, 1477},
134 {"DTMF_KEY_EVENT_7", 7, 852, 1209},
135 {"DTMF_KEY_EVENT_8", 8, 852, 1336},
136 {"DTMF_KEY_EVENT_9", 9, 852, 1477},
137 {"DTMF_KEY_EVENT_S", 10, 941, 1209},
138 {"DTMF_KEY_EVENT_P", 11, 941, 1477},
139 {"DTMF_KEY_EVENT_A", 12, 697, 1633},
140 {"DTMF_KEY_EVENT_B", 13, 770, 1633},
141 {"DTMF_KEY_EVENT_C", 14, 852, 1633},
142 {"DTMF_KEY_EVENT_D", 15, 941, 1633},
145 #define MAX_DTMF_EVENTS 16
149 DTMF_KEY_EVENT_1 = 1,
150 DTMF_KEY_EVENT_2 = 2,
151 DTMF_KEY_EVENT_3 = 3,
152 DTMF_KEY_EVENT_4 = 4,
153 DTMF_KEY_EVENT_5 = 5,
154 DTMF_KEY_EVENT_6 = 6,
155 DTMF_KEY_EVENT_7 = 7,
156 DTMF_KEY_EVENT_8 = 8,
157 DTMF_KEY_EVENT_9 = 9,
158 DTMF_KEY_EVENT_0 = 0,
159 DTMF_KEY_EVENT_STAR = 10,
160 DTMF_KEY_EVENT_POUND = 11,
161 DTMF_KEY_EVENT_A = 12,
162 DTMF_KEY_EVENT_B = 13,
163 DTMF_KEY_EVENT_C = 14,
164 DTMF_KEY_EVENT_D = 15,
167 /* elementfactory information */
168 static const GstElementDetails gst_rtp_dtmfdepay_details =
169 GST_ELEMENT_DETAILS ("RTP DTMF packet depayloader",
170 "Codec/Depayloader/Network",
171 "Generates DTMF Sound from telephone-event RTP packets",
172 "Youness Alaoui <youness.alaoui@collabora.co.uk>");
174 GST_DEBUG_CATEGORY_STATIC (gst_rtp_dtmf_depay_debug);
175 #define GST_CAT_DEFAULT gst_rtp_dtmf_depay_debug
197 static GstStaticPadTemplate gst_rtp_dtmf_depay_src_template =
198 GST_STATIC_PAD_TEMPLATE ("src",
201 GST_STATIC_CAPS ("audio/x-raw-int, "
204 "endianness = (int) " G_STRINGIFY (G_BYTE_ORDER) ", "
205 "signed = (boolean) true, "
206 "rate = (int) [0, MAX], " "channels = (int) 1")
209 static GstStaticPadTemplate gst_rtp_dtmf_depay_sink_template =
210 GST_STATIC_PAD_TEMPLATE ("sink",
213 GST_STATIC_CAPS ("application/x-rtp, "
214 "media = (string) \"audio\", "
215 "payload = (int) " GST_RTP_PAYLOAD_DYNAMIC_STRING ", "
216 "clock-rate = (int) [ 0, MAX ], "
217 "encoding-name = (string) \"TELEPHONE-EVENT\"")
220 GST_BOILERPLATE (GstRtpDTMFDepay, gst_rtp_dtmf_depay, GstBaseRTPDepayload,
221 GST_TYPE_BASE_RTP_DEPAYLOAD);
223 static void gst_rtp_dtmf_depay_set_property (GObject * object, guint prop_id,
224 const GValue * value, GParamSpec * pspec);
225 static void gst_rtp_dtmf_depay_get_property (GObject * object, guint prop_id,
226 GValue * value, GParamSpec * pspec);
227 static GstBuffer *gst_rtp_dtmf_depay_process (GstBaseRTPDepayload * depayload,
229 gboolean gst_rtp_dtmf_depay_setcaps (GstBaseRTPDepayload * filter,
233 gst_rtp_dtmf_depay_base_init (gpointer klass)
235 GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
237 gst_element_class_add_pad_template (element_class,
238 gst_static_pad_template_get (&gst_rtp_dtmf_depay_src_template));
239 gst_element_class_add_pad_template (element_class,
240 gst_static_pad_template_get (&gst_rtp_dtmf_depay_sink_template));
243 GST_DEBUG_CATEGORY_INIT (gst_rtp_dtmf_depay_debug,
244 "rtpdtmfdepay", 0, "rtpdtmfdepay element");
245 gst_element_class_set_details (element_class, &gst_rtp_dtmfdepay_details);
249 gst_rtp_dtmf_depay_class_init (GstRtpDTMFDepayClass * klass)
251 GObjectClass *gobject_class;
252 GstElementClass *gstelement_class;
253 GstBaseRTPDepayloadClass *gstbasertpdepayload_class;
255 gobject_class = (GObjectClass *) klass;
256 gstelement_class = (GstElementClass *) klass;
257 gstbasertpdepayload_class = (GstBaseRTPDepayloadClass *) klass;
259 parent_class = g_type_class_peek_parent (klass);
261 gobject_class->set_property =
262 GST_DEBUG_FUNCPTR (gst_rtp_dtmf_depay_set_property);
263 gobject_class->get_property =
264 GST_DEBUG_FUNCPTR (gst_rtp_dtmf_depay_get_property);
266 g_object_class_install_property (G_OBJECT_CLASS (klass), PROP_UNIT_TIME,
267 g_param_spec_uint ("unit-time", "Duration unittime",
268 "The smallest unit (ms) the duration must be a multiple of (0 disables it)",
269 MIN_UNIT_TIME, MAX_UNIT_TIME, DEFAULT_UNIT_TIME, G_PARAM_READWRITE));
271 g_object_class_install_property (G_OBJECT_CLASS (klass), PROP_MAX_DURATION,
272 g_param_spec_uint ("max-duration", "Maximum duration",
273 "The maxumimum duration (ms) of the outgoing soundpacket. "
274 "(0 = no limit)", 0, G_MAXUINT, DEFAULT_MAX_DURATION,
277 gstbasertpdepayload_class->process =
278 GST_DEBUG_FUNCPTR (gst_rtp_dtmf_depay_process);
279 gstbasertpdepayload_class->set_caps =
280 GST_DEBUG_FUNCPTR (gst_rtp_dtmf_depay_setcaps);
285 gst_rtp_dtmf_depay_init (GstRtpDTMFDepay * rtpdtmfdepay,
286 GstRtpDTMFDepayClass * klass)
288 rtpdtmfdepay->unit_time = DEFAULT_UNIT_TIME;
292 gst_rtp_dtmf_depay_set_property (GObject * object, guint prop_id,
293 const GValue * value, GParamSpec * pspec)
295 GstRtpDTMFDepay *rtpdtmfdepay;
297 rtpdtmfdepay = GST_RTP_DTMF_DEPAY (object);
301 rtpdtmfdepay->unit_time = g_value_get_uint (value);
303 case PROP_MAX_DURATION:
304 rtpdtmfdepay->max_duration = g_value_get_uint (value);
307 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
313 gst_rtp_dtmf_depay_get_property (GObject * object, guint prop_id,
314 GValue * value, GParamSpec * pspec)
316 GstRtpDTMFDepay *rtpdtmfdepay;
318 rtpdtmfdepay = GST_RTP_DTMF_DEPAY (object);
322 g_value_set_uint (value, rtpdtmfdepay->unit_time);
324 case PROP_MAX_DURATION:
325 g_value_set_uint (value, rtpdtmfdepay->max_duration);
328 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
334 gst_rtp_dtmf_depay_setcaps (GstBaseRTPDepayload * filter, GstCaps * caps)
337 GstStructure *structure = gst_caps_get_structure (caps, 0);
338 gint clock_rate = 8000; /* default */
340 gst_structure_get_int (structure, "clock-rate", &clock_rate);
341 filter->clock_rate = clock_rate;
343 srccaps = gst_caps_new_simple ("audio/x-raw-int",
344 "width", G_TYPE_INT, 16,
345 "depth", G_TYPE_INT, 16,
346 "endianness", G_TYPE_INT, G_BYTE_ORDER,
347 "signed", G_TYPE_BOOLEAN, TRUE,
348 "channels", G_TYPE_INT, 1, "rate", G_TYPE_INT, clock_rate, NULL);
349 gst_pad_set_caps (GST_BASE_RTP_DEPAYLOAD_SRCPAD (filter), srccaps);
350 gst_caps_unref (srccaps);
356 gst_dtmf_src_generate_tone (GstRtpDTMFDepay * rtpdtmfdepay,
357 GstRTPDTMFPayload payload, GstBuffer * buffer)
362 double amplitude, f1, f2;
363 double volume_factor;
364 DTMF_KEY key = DTMF_KEYS[payload.event];
365 guint32 clock_rate = 8000 /* default */ ;
366 GstBaseRTPDepayload *depayload = GST_BASE_RTP_DEPAYLOAD (rtpdtmfdepay);
369 clock_rate = depayload->clock_rate;
371 /* Create a buffer for the tone */
372 tone_size = (payload.duration * SAMPLE_SIZE * CHANNELS) / 8;
373 GST_BUFFER_SIZE (buffer) = tone_size;
374 GST_BUFFER_MALLOCDATA (buffer) = g_malloc (tone_size);
375 GST_BUFFER_DATA (buffer) = GST_BUFFER_MALLOCDATA (buffer);
376 GST_BUFFER_DURATION (buffer) = payload.duration * GST_SECOND / clock_rate;
377 volume = payload.volume;
379 p = (gint16 *) GST_BUFFER_MALLOCDATA (buffer);
381 volume_factor = pow (10, (-volume) / 20);
384 * For each sample point we calculate 'x' as the
385 * the amplitude value.
387 for (i = 0; i < (tone_size / (SAMPLE_SIZE / 8)); i++) {
389 * We add the fundamental frequencies together.
391 f1 = sin (2 * M_PI * key.low_frequency * (rtpdtmfdepay->sample /
393 f2 = sin (2 * M_PI * key.high_frequency * (rtpdtmfdepay->sample /
396 amplitude = (f1 + f2) / 2;
398 /* Adjust the volume */
399 amplitude *= volume_factor;
401 /* Make the [-1:1] interval into a [-32767:32767] interval */
404 /* Store it in the data buffer */
405 *(p++) = (gint16) amplitude;
407 (rtpdtmfdepay->sample)++;
413 gst_rtp_dtmf_depay_process (GstBaseRTPDepayload * depayload, GstBuffer * buf)
416 GstRtpDTMFDepay *rtpdtmfdepay = NULL;
417 GstBuffer *outbuf = NULL;
419 guint8 *payload = NULL;
421 GstRTPDTMFPayload dtmf_payload;
423 GstStructure *structure = NULL;
424 GstMessage *dtmf_message = NULL;
426 rtpdtmfdepay = GST_RTP_DTMF_DEPAY (depayload);
428 if (!gst_rtp_buffer_validate (buf))
431 payload_len = gst_rtp_buffer_get_payload_len (buf);
432 payload = gst_rtp_buffer_get_payload (buf);
434 if (payload_len != sizeof (GstRTPDTMFPayload))
437 memcpy (&dtmf_payload, payload, sizeof (GstRTPDTMFPayload));
439 if (dtmf_payload.event > MAX_EVENT)
443 marker = gst_rtp_buffer_get_marker (buf);
445 timestamp = gst_rtp_buffer_get_timestamp (buf);
447 dtmf_payload.duration = g_ntohs (dtmf_payload.duration);
449 /* clip to whole units of unit_time */
450 if (rtpdtmfdepay->unit_time) {
451 guint unit_time_clock =
452 (rtpdtmfdepay->unit_time * depayload->clock_rate) / 1000;
453 if (dtmf_payload.duration % unit_time_clock) {
454 /* Make sure we don't overflow the duration */
455 if (dtmf_payload.duration < G_MAXUINT16 - unit_time_clock)
456 dtmf_payload.duration += unit_time_clock -
457 (dtmf_payload.duration % unit_time_clock);
459 dtmf_payload.duration -= dtmf_payload.duration % unit_time_clock;
463 /* clip to max duration */
464 if (rtpdtmfdepay->max_duration) {
465 guint max_duration_clock =
466 (rtpdtmfdepay->max_duration * depayload->clock_rate) / 1000;
468 if (max_duration_clock < G_MAXUINT16 &&
469 dtmf_payload.duration > max_duration_clock)
470 dtmf_payload.duration = max_duration_clock;
473 GST_DEBUG_OBJECT (depayload, "Received new RTP DTMF packet : "
474 "marker=%d - timestamp=%u - event=%d - duration=%d",
475 marker, timestamp, dtmf_payload.event, dtmf_payload.duration);
477 GST_DEBUG_OBJECT (depayload,
478 "Previous information : timestamp=%u - duration=%d",
479 rtpdtmfdepay->previous_ts, rtpdtmfdepay->previous_duration);
482 if (marker || rtpdtmfdepay->previous_ts != timestamp) {
483 rtpdtmfdepay->sample = 0;
484 rtpdtmfdepay->previous_ts = timestamp;
485 rtpdtmfdepay->previous_duration = dtmf_payload.duration;
486 rtpdtmfdepay->first_gst_ts = GST_BUFFER_TIMESTAMP (buf);
488 structure = gst_structure_new ("dtmf-event",
489 "number", G_TYPE_INT, dtmf_payload.event,
490 "volume", G_TYPE_INT, dtmf_payload.volume,
491 "type", G_TYPE_INT, 1, "method", G_TYPE_INT, 1, NULL);
494 gst_message_new_element (GST_OBJECT (depayload), structure);
496 if (!gst_element_post_message (GST_ELEMENT (depayload), dtmf_message)) {
497 GST_ERROR_OBJECT (depayload,
498 "Unable to send dtmf-event message to bus");
501 GST_ERROR_OBJECT (depayload, "Unable to create dtmf-event message");
504 GST_ERROR_OBJECT (depayload, "Unable to create dtmf-event structure");
507 guint16 duration = dtmf_payload.duration;
508 dtmf_payload.duration -= rtpdtmfdepay->previous_duration;
509 /* If late buffer, ignore */
510 if (duration > rtpdtmfdepay->previous_duration)
511 rtpdtmfdepay->previous_duration = duration;
514 GST_DEBUG_OBJECT (depayload, "new previous duration : %d - new duration : %d"
515 " - diff : %d - clock rate : %d - timestamp : %llu",
516 rtpdtmfdepay->previous_duration, dtmf_payload.duration,
517 (rtpdtmfdepay->previous_duration - dtmf_payload.duration),
518 depayload->clock_rate, GST_BUFFER_TIMESTAMP (buf));
520 /* If late or duplicate packet (like the redundant end packet). Ignore */
521 if (dtmf_payload.duration > 0) {
522 outbuf = gst_buffer_new ();
523 gst_dtmf_src_generate_tone (rtpdtmfdepay, dtmf_payload, outbuf);
526 GST_BUFFER_TIMESTAMP (outbuf) = rtpdtmfdepay->first_gst_ts +
527 (rtpdtmfdepay->previous_duration - dtmf_payload.duration) *
528 GST_SECOND / depayload->clock_rate;
529 GST_BUFFER_OFFSET (outbuf) =
530 (rtpdtmfdepay->previous_duration - dtmf_payload.duration) *
531 GST_SECOND / depayload->clock_rate;
532 GST_BUFFER_OFFSET_END (outbuf) = rtpdtmfdepay->previous_duration *
533 GST_SECOND / depayload->clock_rate;
535 GST_DEBUG_OBJECT (depayload, "timestamp : %llu - time %" GST_TIME_FORMAT,
536 GST_BUFFER_TIMESTAMP (buf), GST_TIME_ARGS (GST_BUFFER_TIMESTAMP (buf)));
544 GST_ELEMENT_WARNING (rtpdtmfdepay, STREAM, DECODE,
545 ("Packet did not validate"), (NULL));
550 gst_rtp_dtmf_depay_plugin_init (GstPlugin * plugin)
552 return gst_element_register (plugin, "rtpdtmfdepay",
553 GST_RANK_MARGINAL, GST_TYPE_RTP_DTMF_DEPAY);