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
120 const char *event_name;
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 GST_DEBUG_CATEGORY_STATIC (gst_rtp_dtmf_depay_debug);
168 #define GST_CAT_DEFAULT gst_rtp_dtmf_depay_debug
190 static GstStaticPadTemplate gst_rtp_dtmf_depay_src_template =
191 GST_STATIC_PAD_TEMPLATE ("src",
194 GST_STATIC_CAPS ("audio/x-raw-int, "
197 "endianness = (int) " G_STRINGIFY (G_BYTE_ORDER) ", "
198 "signed = (boolean) true, "
199 "rate = (int) [0, MAX], " "channels = (int) 1")
202 static GstStaticPadTemplate gst_rtp_dtmf_depay_sink_template =
203 GST_STATIC_PAD_TEMPLATE ("sink",
206 GST_STATIC_CAPS ("application/x-rtp, "
207 "media = (string) \"audio\", "
208 "payload = (int) " GST_RTP_PAYLOAD_DYNAMIC_STRING ", "
209 "clock-rate = (int) [ 0, MAX ], "
210 "encoding-name = (string) \"TELEPHONE-EVENT\"")
213 GST_BOILERPLATE (GstRtpDTMFDepay, gst_rtp_dtmf_depay, GstBaseRTPDepayload,
214 GST_TYPE_BASE_RTP_DEPAYLOAD);
216 static void gst_rtp_dtmf_depay_set_property (GObject * object, guint prop_id,
217 const GValue * value, GParamSpec * pspec);
218 static void gst_rtp_dtmf_depay_get_property (GObject * object, guint prop_id,
219 GValue * value, GParamSpec * pspec);
220 static GstBuffer *gst_rtp_dtmf_depay_process (GstBaseRTPDepayload * depayload,
222 gboolean gst_rtp_dtmf_depay_setcaps (GstBaseRTPDepayload * filter,
226 gst_rtp_dtmf_depay_base_init (gpointer klass)
228 GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
230 gst_element_class_add_pad_template (element_class,
231 gst_static_pad_template_get (&gst_rtp_dtmf_depay_src_template));
232 gst_element_class_add_pad_template (element_class,
233 gst_static_pad_template_get (&gst_rtp_dtmf_depay_sink_template));
236 GST_DEBUG_CATEGORY_INIT (gst_rtp_dtmf_depay_debug,
237 "rtpdtmfdepay", 0, "rtpdtmfdepay element");
238 gst_element_class_set_details_simple (element_class,
239 "RTP DTMF packet depayloader", "Codec/Depayloader/Network",
240 "Generates DTMF Sound from telephone-event RTP packets",
241 "Youness Alaoui <youness.alaoui@collabora.co.uk>");
245 gst_rtp_dtmf_depay_class_init (GstRtpDTMFDepayClass * klass)
247 GObjectClass *gobject_class;
248 GstElementClass *gstelement_class;
249 GstBaseRTPDepayloadClass *gstbasertpdepayload_class;
251 gobject_class = (GObjectClass *) klass;
252 gstelement_class = (GstElementClass *) klass;
253 gstbasertpdepayload_class = (GstBaseRTPDepayloadClass *) klass;
255 parent_class = g_type_class_peek_parent (klass);
257 gobject_class->set_property =
258 GST_DEBUG_FUNCPTR (gst_rtp_dtmf_depay_set_property);
259 gobject_class->get_property =
260 GST_DEBUG_FUNCPTR (gst_rtp_dtmf_depay_get_property);
262 g_object_class_install_property (G_OBJECT_CLASS (klass), PROP_UNIT_TIME,
263 g_param_spec_uint ("unit-time", "Duration unittime",
264 "The smallest unit (ms) the duration must be a multiple of (0 disables it)",
265 MIN_UNIT_TIME, MAX_UNIT_TIME, DEFAULT_UNIT_TIME, G_PARAM_READWRITE));
267 g_object_class_install_property (G_OBJECT_CLASS (klass), PROP_MAX_DURATION,
268 g_param_spec_uint ("max-duration", "Maximum duration",
269 "The maxumimum duration (ms) of the outgoing soundpacket. "
270 "(0 = no limit)", 0, G_MAXUINT, DEFAULT_MAX_DURATION,
273 gstbasertpdepayload_class->process =
274 GST_DEBUG_FUNCPTR (gst_rtp_dtmf_depay_process);
275 gstbasertpdepayload_class->set_caps =
276 GST_DEBUG_FUNCPTR (gst_rtp_dtmf_depay_setcaps);
281 gst_rtp_dtmf_depay_init (GstRtpDTMFDepay * rtpdtmfdepay,
282 GstRtpDTMFDepayClass * klass)
284 rtpdtmfdepay->unit_time = DEFAULT_UNIT_TIME;
288 gst_rtp_dtmf_depay_set_property (GObject * object, guint prop_id,
289 const GValue * value, GParamSpec * pspec)
291 GstRtpDTMFDepay *rtpdtmfdepay;
293 rtpdtmfdepay = GST_RTP_DTMF_DEPAY (object);
297 rtpdtmfdepay->unit_time = g_value_get_uint (value);
299 case PROP_MAX_DURATION:
300 rtpdtmfdepay->max_duration = g_value_get_uint (value);
303 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
309 gst_rtp_dtmf_depay_get_property (GObject * object, guint prop_id,
310 GValue * value, GParamSpec * pspec)
312 GstRtpDTMFDepay *rtpdtmfdepay;
314 rtpdtmfdepay = GST_RTP_DTMF_DEPAY (object);
318 g_value_set_uint (value, rtpdtmfdepay->unit_time);
320 case PROP_MAX_DURATION:
321 g_value_set_uint (value, rtpdtmfdepay->max_duration);
324 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
330 gst_rtp_dtmf_depay_setcaps (GstBaseRTPDepayload * filter, GstCaps * caps)
333 GstStructure *structure = gst_caps_get_structure (caps, 0);
334 gint clock_rate = 8000; /* default */
336 gst_structure_get_int (structure, "clock-rate", &clock_rate);
337 filter->clock_rate = clock_rate;
339 srccaps = gst_caps_new_simple ("audio/x-raw-int",
340 "width", G_TYPE_INT, 16,
341 "depth", G_TYPE_INT, 16,
342 "endianness", G_TYPE_INT, G_BYTE_ORDER,
343 "signed", G_TYPE_BOOLEAN, TRUE,
344 "channels", G_TYPE_INT, 1, "rate", G_TYPE_INT, clock_rate, NULL);
345 gst_pad_set_caps (GST_BASE_RTP_DEPAYLOAD_SRCPAD (filter), srccaps);
346 gst_caps_unref (srccaps);
352 gst_dtmf_src_generate_tone (GstRtpDTMFDepay * rtpdtmfdepay,
353 GstRTPDTMFPayload payload, GstBuffer * buffer)
358 double amplitude, f1, f2;
359 double volume_factor;
360 DTMF_KEY key = DTMF_KEYS[payload.event];
361 guint32 clock_rate = 8000 /* default */ ;
362 GstBaseRTPDepayload *depayload = GST_BASE_RTP_DEPAYLOAD (rtpdtmfdepay);
365 clock_rate = depayload->clock_rate;
367 /* Create a buffer for the tone */
368 tone_size = (payload.duration * SAMPLE_SIZE * CHANNELS) / 8;
369 GST_BUFFER_SIZE (buffer) = tone_size;
370 GST_BUFFER_MALLOCDATA (buffer) = g_malloc (tone_size);
371 GST_BUFFER_DATA (buffer) = GST_BUFFER_MALLOCDATA (buffer);
372 GST_BUFFER_DURATION (buffer) = payload.duration * GST_SECOND / clock_rate;
373 volume = payload.volume;
375 p = (gint16 *) GST_BUFFER_MALLOCDATA (buffer);
377 volume_factor = pow (10, (-volume) / 20);
380 * For each sample point we calculate 'x' as the
381 * the amplitude value.
383 for (i = 0; i < (tone_size / (SAMPLE_SIZE / 8)); i++) {
385 * We add the fundamental frequencies together.
387 f1 = sin (2 * M_PI * key.low_frequency * (rtpdtmfdepay->sample /
389 f2 = sin (2 * M_PI * key.high_frequency * (rtpdtmfdepay->sample /
392 amplitude = (f1 + f2) / 2;
394 /* Adjust the volume */
395 amplitude *= volume_factor;
397 /* Make the [-1:1] interval into a [-32767:32767] interval */
400 /* Store it in the data buffer */
401 *(p++) = (gint16) amplitude;
403 (rtpdtmfdepay->sample)++;
409 gst_rtp_dtmf_depay_process (GstBaseRTPDepayload * depayload, GstBuffer * buf)
412 GstRtpDTMFDepay *rtpdtmfdepay = NULL;
413 GstBuffer *outbuf = NULL;
415 guint8 *payload = NULL;
417 GstRTPDTMFPayload dtmf_payload;
419 GstStructure *structure = NULL;
420 GstMessage *dtmf_message = NULL;
422 rtpdtmfdepay = GST_RTP_DTMF_DEPAY (depayload);
424 if (!gst_rtp_buffer_validate (buf))
427 payload_len = gst_rtp_buffer_get_payload_len (buf);
428 payload = gst_rtp_buffer_get_payload (buf);
430 if (payload_len != sizeof (GstRTPDTMFPayload))
433 memcpy (&dtmf_payload, payload, sizeof (GstRTPDTMFPayload));
435 if (dtmf_payload.event > MAX_EVENT)
439 marker = gst_rtp_buffer_get_marker (buf);
441 timestamp = gst_rtp_buffer_get_timestamp (buf);
443 dtmf_payload.duration = g_ntohs (dtmf_payload.duration);
445 /* clip to whole units of unit_time */
446 if (rtpdtmfdepay->unit_time) {
447 guint unit_time_clock =
448 (rtpdtmfdepay->unit_time * depayload->clock_rate) / 1000;
449 if (dtmf_payload.duration % unit_time_clock) {
450 /* Make sure we don't overflow the duration */
451 if (dtmf_payload.duration < G_MAXUINT16 - unit_time_clock)
452 dtmf_payload.duration += unit_time_clock -
453 (dtmf_payload.duration % unit_time_clock);
455 dtmf_payload.duration -= dtmf_payload.duration % unit_time_clock;
459 /* clip to max duration */
460 if (rtpdtmfdepay->max_duration) {
461 guint max_duration_clock =
462 (rtpdtmfdepay->max_duration * depayload->clock_rate) / 1000;
464 if (max_duration_clock < G_MAXUINT16 &&
465 dtmf_payload.duration > max_duration_clock)
466 dtmf_payload.duration = max_duration_clock;
469 GST_DEBUG_OBJECT (depayload, "Received new RTP DTMF packet : "
470 "marker=%d - timestamp=%u - event=%d - duration=%d",
471 marker, timestamp, dtmf_payload.event, dtmf_payload.duration);
473 GST_DEBUG_OBJECT (depayload,
474 "Previous information : timestamp=%u - duration=%d",
475 rtpdtmfdepay->previous_ts, rtpdtmfdepay->previous_duration);
478 if (marker || rtpdtmfdepay->previous_ts != timestamp) {
479 rtpdtmfdepay->sample = 0;
480 rtpdtmfdepay->previous_ts = timestamp;
481 rtpdtmfdepay->previous_duration = dtmf_payload.duration;
482 rtpdtmfdepay->first_gst_ts = GST_BUFFER_TIMESTAMP (buf);
484 structure = gst_structure_new ("dtmf-event",
485 "number", G_TYPE_INT, dtmf_payload.event,
486 "volume", G_TYPE_INT, dtmf_payload.volume,
487 "type", G_TYPE_INT, 1, "method", G_TYPE_INT, 1, NULL);
490 gst_message_new_element (GST_OBJECT (depayload), structure);
492 if (!gst_element_post_message (GST_ELEMENT (depayload), dtmf_message)) {
493 GST_ERROR_OBJECT (depayload,
494 "Unable to send dtmf-event message to bus");
497 GST_ERROR_OBJECT (depayload, "Unable to create dtmf-event message");
500 GST_ERROR_OBJECT (depayload, "Unable to create dtmf-event structure");
503 guint16 duration = dtmf_payload.duration;
504 dtmf_payload.duration -= rtpdtmfdepay->previous_duration;
505 /* If late buffer, ignore */
506 if (duration > rtpdtmfdepay->previous_duration)
507 rtpdtmfdepay->previous_duration = duration;
510 GST_DEBUG_OBJECT (depayload, "new previous duration : %d - new duration : %d"
511 " - diff : %d - clock rate : %d - timestamp : %" G_GUINT64_FORMAT,
512 rtpdtmfdepay->previous_duration, dtmf_payload.duration,
513 (rtpdtmfdepay->previous_duration - dtmf_payload.duration),
514 depayload->clock_rate, GST_BUFFER_TIMESTAMP (buf));
516 /* If late or duplicate packet (like the redundant end packet). Ignore */
517 if (dtmf_payload.duration > 0) {
518 outbuf = gst_buffer_new ();
519 gst_dtmf_src_generate_tone (rtpdtmfdepay, dtmf_payload, outbuf);
522 GST_BUFFER_TIMESTAMP (outbuf) = rtpdtmfdepay->first_gst_ts +
523 (rtpdtmfdepay->previous_duration - dtmf_payload.duration) *
524 GST_SECOND / depayload->clock_rate;
525 GST_BUFFER_OFFSET (outbuf) =
526 (rtpdtmfdepay->previous_duration - dtmf_payload.duration) *
527 GST_SECOND / depayload->clock_rate;
528 GST_BUFFER_OFFSET_END (outbuf) = rtpdtmfdepay->previous_duration *
529 GST_SECOND / depayload->clock_rate;
531 GST_DEBUG_OBJECT (depayload,
532 "timestamp : %" G_GUINT64_FORMAT " - time %" GST_TIME_FORMAT,
533 GST_BUFFER_TIMESTAMP (buf), GST_TIME_ARGS (GST_BUFFER_TIMESTAMP (buf)));
541 GST_ELEMENT_WARNING (rtpdtmfdepay, STREAM, DECODE,
542 ("Packet did not validate"), (NULL));
547 gst_rtp_dtmf_depay_plugin_init (GstPlugin * plugin)
549 return gst_element_register (plugin, "rtpdtmfdepay",
550 GST_RANK_MARGINAL, GST_TYPE_RTP_DTMF_DEPAY);