1 /*
2  * Siren Payloader Gst Element
3  *
4  *   @author: Youness Alaoui <kakaroto@kakaroto.homelinux.net>
5  *
6  * This library is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Library General Public
8  * License as published by the Free Software Foundation; either
9  * version 2 of the License, or (at your option) any later version.
10  *
11  * This library is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * Library General Public License for more details.
15  *
16  * You should have received a copy of the GNU Library General Public
17  * License along with this library; if not, write to the
18  * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
19  * Boston, MA 02110-1301, USA.
20  */
21 
22 #ifdef HAVE_CONFIG_H
23 #include "config.h"
24 #endif
25 
26 #include "gstrtpsirenpay.h"
27 #include <gst/rtp/gstrtpbuffer.h>
28 
29 GST_DEBUG_CATEGORY_STATIC (rtpsirenpay_debug);
30 #define GST_CAT_DEFAULT (rtpsirenpay_debug)
31 
32 static GstStaticPadTemplate gst_rtp_siren_pay_sink_template =
33 GST_STATIC_PAD_TEMPLATE ("sink",
34     GST_PAD_SINK,
35     GST_PAD_ALWAYS,
36     GST_STATIC_CAPS ("audio/x-siren, " "dct-length = (int) 320")
37     );
38 
39 static GstStaticPadTemplate gst_rtp_siren_pay_src_template =
40 GST_STATIC_PAD_TEMPLATE ("src",
41     GST_PAD_SRC,
42     GST_PAD_ALWAYS,
43     GST_STATIC_CAPS ("application/x-rtp, "
44         "media = (string) \"audio\", "
45         "payload = (int) " GST_RTP_PAYLOAD_DYNAMIC_STRING ", "
46         "clock-rate = (int) 16000, "
47         "encoding-name = (string) \"SIREN\", "
48         "bitrate = (string) \"16000\", " "dct-length = (int) 320")
49     );
50 
51 static gboolean gst_rtp_siren_pay_setcaps (GstRTPBasePayload * payload,
52     GstCaps * caps);
53 
54 G_DEFINE_TYPE (GstRTPSirenPay, gst_rtp_siren_pay,
55     GST_TYPE_RTP_BASE_AUDIO_PAYLOAD);
56 
57 static void
gst_rtp_siren_pay_class_init(GstRTPSirenPayClass * klass)58 gst_rtp_siren_pay_class_init (GstRTPSirenPayClass * klass)
59 {
60   GstElementClass *gstelement_class;
61   GstRTPBasePayloadClass *gstrtpbasepayload_class;
62 
63   gstelement_class = (GstElementClass *) klass;
64   gstrtpbasepayload_class = (GstRTPBasePayloadClass *) klass;
65 
66   gstrtpbasepayload_class->set_caps = gst_rtp_siren_pay_setcaps;
67 
68   gst_element_class_add_static_pad_template (gstelement_class,
69       &gst_rtp_siren_pay_sink_template);
70   gst_element_class_add_static_pad_template (gstelement_class,
71       &gst_rtp_siren_pay_src_template);
72   gst_element_class_set_static_metadata (gstelement_class,
73       "RTP Payloader for Siren Audio", "Codec/Payloader/Network/RTP",
74       "Packetize Siren audio streams into RTP packets",
75       "Youness Alaoui <kakaroto@kakaroto.homelinux.net>");
76 
77   GST_DEBUG_CATEGORY_INIT (rtpsirenpay_debug, "rtpsirenpay", 0,
78       "siren audio RTP payloader");
79 }
80 
81 static void
gst_rtp_siren_pay_init(GstRTPSirenPay * rtpsirenpay)82 gst_rtp_siren_pay_init (GstRTPSirenPay * rtpsirenpay)
83 {
84   GstRTPBasePayload *rtpbasepayload;
85   GstRTPBaseAudioPayload *rtpbaseaudiopayload;
86 
87   rtpbasepayload = GST_RTP_BASE_PAYLOAD (rtpsirenpay);
88   rtpbaseaudiopayload = GST_RTP_BASE_AUDIO_PAYLOAD (rtpsirenpay);
89 
90   /* we don't set the payload type, it should be set by the application using
91    * the pt property or the default 96 will be used */
92   rtpbasepayload->clock_rate = 16000;
93 
94   /* tell rtpbaseaudiopayload that this is a frame based codec */
95   gst_rtp_base_audio_payload_set_frame_based (rtpbaseaudiopayload);
96 }
97 
98 static gboolean
gst_rtp_siren_pay_setcaps(GstRTPBasePayload * rtpbasepayload,GstCaps * caps)99 gst_rtp_siren_pay_setcaps (GstRTPBasePayload * rtpbasepayload, GstCaps * caps)
100 {
101   GstRTPSirenPay *rtpsirenpay;
102   GstRTPBaseAudioPayload *rtpbaseaudiopayload;
103   gint dct_length;
104   GstStructure *structure;
105   const char *payload_name;
106 
107   rtpsirenpay = GST_RTP_SIREN_PAY (rtpbasepayload);
108   rtpbaseaudiopayload = GST_RTP_BASE_AUDIO_PAYLOAD (rtpbasepayload);
109 
110   structure = gst_caps_get_structure (caps, 0);
111 
112   gst_structure_get_int (structure, "dct-length", &dct_length);
113   if (dct_length != 320)
114     goto wrong_dct;
115 
116   payload_name = gst_structure_get_name (structure);
117   if (g_ascii_strcasecmp ("audio/x-siren", payload_name))
118     goto wrong_caps;
119 
120   gst_rtp_base_payload_set_options (rtpbasepayload, "audio", TRUE, "SIREN",
121       16000);
122   /* set options for this frame based audio codec */
123   gst_rtp_base_audio_payload_set_frame_options (rtpbaseaudiopayload, 20, 40);
124 
125   return gst_rtp_base_payload_set_outcaps (rtpbasepayload, NULL);
126 
127   /* ERRORS */
128 wrong_dct:
129   {
130     GST_ERROR_OBJECT (rtpsirenpay, "dct-length must be 320, received %d",
131         dct_length);
132     return FALSE;
133   }
134 wrong_caps:
135   {
136     GST_ERROR_OBJECT (rtpsirenpay, "expected audio/x-siren, received %s",
137         payload_name);
138     return FALSE;
139   }
140 }
141 
142 gboolean
gst_rtp_siren_pay_plugin_init(GstPlugin * plugin)143 gst_rtp_siren_pay_plugin_init (GstPlugin * plugin)
144 {
145   return gst_element_register (plugin, "rtpsirenpay",
146       GST_RANK_SECONDARY, GST_TYPE_RTP_SIREN_PAY);
147 }
148