1 /* GStreamer
2 * Copyright (C) <2009> Wim Taymans <wim.taymans@gmail.com>
3 *
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Library General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
8 *
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Library General Public License for more details.
13 *
14 * You should have received a copy of the GNU Library General Public
15 * License along with this library; if not, write to the
16 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
17 * Boston, MA 02110-1301, USA.
18 */
19
20 /**
21 * SECTION:element-rtpbvdepay
22 * @see_also: rtpbvpay
23 *
24 * Extract BroadcomVoice audio from RTP packets according to RFC 4298.
25 * For detailed information see: http://www.rfc-editor.org/rfc/rfc4298.txt
26 */
27
28 #ifdef HAVE_CONFIG_H
29 # include "config.h"
30 #endif
31
32 #include <string.h>
33 #include <stdlib.h>
34
35 #include <gst/rtp/gstrtpbuffer.h>
36 #include <gst/audio/audio.h>
37 #include "gstrtpbvdepay.h"
38 #include "gstrtputils.h"
39
40 static GstStaticPadTemplate gst_rtp_bv_depay_sink_template =
41 GST_STATIC_PAD_TEMPLATE ("sink",
42 GST_PAD_SINK,
43 GST_PAD_ALWAYS,
44 GST_STATIC_CAPS ("application/x-rtp, "
45 "media = (string) \"audio\", "
46 "clock-rate = (int) 8000, "
47 "encoding-name = (string) \"BV16\"; "
48 "application/x-rtp, "
49 "media = (string) \"audio\", "
50 "clock-rate = (int) 16000, " "encoding-name = (string) \"BV32\"")
51 );
52
53 static GstStaticPadTemplate gst_rtp_bv_depay_src_template =
54 GST_STATIC_PAD_TEMPLATE ("src",
55 GST_PAD_SRC,
56 GST_PAD_ALWAYS,
57 GST_STATIC_CAPS ("audio/x-bv, " "mode = (int) { 16, 32 }")
58 );
59
60 static GstBuffer *gst_rtp_bv_depay_process (GstRTPBaseDepayload * depayload,
61 GstRTPBuffer * rtp);
62 static gboolean gst_rtp_bv_depay_setcaps (GstRTPBaseDepayload * depayload,
63 GstCaps * caps);
64
65 #define gst_rtp_bv_depay_parent_class parent_class
66 G_DEFINE_TYPE (GstRTPBVDepay, gst_rtp_bv_depay, GST_TYPE_RTP_BASE_DEPAYLOAD);
67
68 static void
gst_rtp_bv_depay_class_init(GstRTPBVDepayClass * klass)69 gst_rtp_bv_depay_class_init (GstRTPBVDepayClass * klass)
70 {
71 GstElementClass *gstelement_class;
72 GstRTPBaseDepayloadClass *gstrtpbasedepayload_class;
73
74 gstelement_class = (GstElementClass *) klass;
75 gstrtpbasedepayload_class = (GstRTPBaseDepayloadClass *) klass;
76
77 gst_element_class_add_static_pad_template (gstelement_class,
78 &gst_rtp_bv_depay_src_template);
79 gst_element_class_add_static_pad_template (gstelement_class,
80 &gst_rtp_bv_depay_sink_template);
81
82 gst_element_class_set_static_metadata (gstelement_class,
83 "RTP BroadcomVoice depayloader", "Codec/Depayloader/Network/RTP",
84 "Extracts BroadcomVoice audio from RTP packets (RFC 4298)",
85 "Wim Taymans <wim.taymans@collabora.co.uk>");
86
87 gstrtpbasedepayload_class->process_rtp_packet = gst_rtp_bv_depay_process;
88 gstrtpbasedepayload_class->set_caps = gst_rtp_bv_depay_setcaps;
89 }
90
91 static void
gst_rtp_bv_depay_init(GstRTPBVDepay * rtpbvdepay)92 gst_rtp_bv_depay_init (GstRTPBVDepay * rtpbvdepay)
93 {
94 rtpbvdepay->mode = -1;
95 }
96
97 static gboolean
gst_rtp_bv_depay_setcaps(GstRTPBaseDepayload * depayload,GstCaps * caps)98 gst_rtp_bv_depay_setcaps (GstRTPBaseDepayload * depayload, GstCaps * caps)
99 {
100 GstRTPBVDepay *rtpbvdepay = GST_RTP_BV_DEPAY (depayload);
101 GstCaps *srccaps;
102 GstStructure *structure;
103 const gchar *mode_str = NULL;
104 gint mode, clock_rate, expected_rate;
105 gboolean ret;
106
107 structure = gst_caps_get_structure (caps, 0);
108
109 mode_str = gst_structure_get_string (structure, "encoding-name");
110 if (!mode_str)
111 goto no_mode;
112
113 if (!strcmp (mode_str, "BV16")) {
114 mode = 16;
115 expected_rate = 8000;
116 } else if (!strcmp (mode_str, "BV32")) {
117 mode = 32;
118 expected_rate = 16000;
119 } else
120 goto invalid_mode;
121
122 if (!gst_structure_get_int (structure, "clock-rate", &clock_rate))
123 clock_rate = expected_rate;
124 else if (clock_rate != expected_rate)
125 goto wrong_rate;
126
127 depayload->clock_rate = clock_rate;
128 rtpbvdepay->mode = mode;
129
130 srccaps = gst_caps_new_simple ("audio/x-bv",
131 "mode", G_TYPE_INT, rtpbvdepay->mode, NULL);
132 ret = gst_pad_set_caps (GST_RTP_BASE_DEPAYLOAD_SRCPAD (depayload), srccaps);
133
134 GST_DEBUG ("set caps on source: %" GST_PTR_FORMAT " (ret=%d)", srccaps, ret);
135 gst_caps_unref (srccaps);
136
137 return ret;
138
139 /* ERRORS */
140 no_mode:
141 {
142 GST_ERROR_OBJECT (rtpbvdepay, "did not receive an encoding-name");
143 return FALSE;
144 }
145 invalid_mode:
146 {
147 GST_ERROR_OBJECT (rtpbvdepay,
148 "invalid encoding-name, expected BV16 or BV32, got %s", mode_str);
149 return FALSE;
150 }
151 wrong_rate:
152 {
153 GST_ERROR_OBJECT (rtpbvdepay, "invalid clock-rate, expected %d, got %d",
154 expected_rate, clock_rate);
155 return FALSE;
156 }
157 }
158
159 static GstBuffer *
gst_rtp_bv_depay_process(GstRTPBaseDepayload * depayload,GstRTPBuffer * rtp)160 gst_rtp_bv_depay_process (GstRTPBaseDepayload * depayload, GstRTPBuffer * rtp)
161 {
162 GstBuffer *outbuf;
163 gboolean marker;
164
165 marker = gst_rtp_buffer_get_marker (rtp);
166
167 GST_DEBUG ("process : got %" G_GSIZE_FORMAT " bytes, mark %d ts %u seqn %d",
168 gst_buffer_get_size (rtp->buffer), marker,
169 gst_rtp_buffer_get_timestamp (rtp), gst_rtp_buffer_get_seq (rtp));
170
171 outbuf = gst_rtp_buffer_get_payload_buffer (rtp);
172
173 if (marker && outbuf) {
174 /* mark start of talkspurt with RESYNC */
175 GST_BUFFER_FLAG_SET (outbuf, GST_BUFFER_FLAG_RESYNC);
176 }
177
178 if (outbuf) {
179 gst_rtp_drop_non_audio_meta (depayload, outbuf);
180 }
181
182 return outbuf;
183 }
184
185 gboolean
gst_rtp_bv_depay_plugin_init(GstPlugin * plugin)186 gst_rtp_bv_depay_plugin_init (GstPlugin * plugin)
187 {
188 return gst_element_register (plugin, "rtpbvdepay",
189 GST_RANK_SECONDARY, GST_TYPE_RTP_BV_DEPAY);
190 }
191