1 /*
2 * gstrtponviftimestamp-parse.c
3 *
4 * Copyright (C) 2014 Axis Communications AB
5 * Author: Guillaume Desmottes <guillaume.desmottes@collabora.com>
6 *
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
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 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
19 */
20
21 #ifdef HAVE_CONFIG_H
22 #include "config.h"
23 #endif
24
25 #include <stdio.h>
26 #include <stdlib.h>
27 #include <string.h>
28
29 #include <gst/rtp/gstrtpbuffer.h>
30
31 #include "gstrtponvifparse.h"
32
33 static GstFlowReturn gst_rtp_onvif_parse_chain (GstPad * pad,
34 GstObject * parent, GstBuffer * buf);
35
36 static GstStaticPadTemplate sink_template_factory =
37 GST_STATIC_PAD_TEMPLATE ("sink",
38 GST_PAD_SINK,
39 GST_PAD_ALWAYS,
40 GST_STATIC_CAPS ("application/x-rtp")
41 );
42
43 static GstStaticPadTemplate src_template_factory =
44 GST_STATIC_PAD_TEMPLATE ("src",
45 GST_PAD_SRC,
46 GST_PAD_ALWAYS,
47 GST_STATIC_CAPS ("application/x-rtp")
48 );
49
50 G_DEFINE_TYPE (GstRtpOnvifParse, gst_rtp_onvif_parse, GST_TYPE_ELEMENT);
51 GST_ELEMENT_REGISTER_DEFINE (rtponvifparse, "rtponvifparse",
52 GST_RANK_NONE, GST_TYPE_RTP_ONVIF_PARSE);
53
54 static void
gst_rtp_onvif_parse_class_init(GstRtpOnvifParseClass * klass)55 gst_rtp_onvif_parse_class_init (GstRtpOnvifParseClass * klass)
56 {
57 GstElementClass *gstelement_class;
58
59 gstelement_class = GST_ELEMENT_CLASS (klass);
60
61 /* register pads */
62 gst_element_class_add_static_pad_template (gstelement_class,
63 &sink_template_factory);
64 gst_element_class_add_static_pad_template (gstelement_class,
65 &src_template_factory);
66
67 gst_element_class_set_static_metadata (gstelement_class,
68 "ONVIF NTP timestamps RTP extension", "Effect/RTP",
69 "Add absolute timestamps and flags of recorded data in a playback "
70 "session", "Guillaume Desmottes <guillaume.desmottes@collabora.com>");
71 }
72
73 static void
gst_rtp_onvif_parse_init(GstRtpOnvifParse * self)74 gst_rtp_onvif_parse_init (GstRtpOnvifParse * self)
75 {
76 self->sinkpad =
77 gst_pad_new_from_static_template (&sink_template_factory, "sink");
78 gst_pad_set_chain_function (self->sinkpad, gst_rtp_onvif_parse_chain);
79 gst_element_add_pad (GST_ELEMENT (self), self->sinkpad);
80 GST_PAD_SET_PROXY_CAPS (self->sinkpad);
81
82 self->srcpad =
83 gst_pad_new_from_static_template (&src_template_factory, "src");
84 gst_element_add_pad (GST_ELEMENT (self), self->srcpad);
85 }
86
87 #define EXTENSION_ID 0xABAC
88 #define EXTENSION_SIZE 3
89
90 static gboolean
handle_buffer(GstRtpOnvifParse * self,GstBuffer * buf,gboolean * send_eos)91 handle_buffer (GstRtpOnvifParse * self, GstBuffer * buf, gboolean * send_eos)
92 {
93 GstRTPBuffer rtp = GST_RTP_BUFFER_INIT;
94 guint8 *data;
95 guint16 bits;
96 guint wordlen;
97 guint8 flags;
98 guint64 timestamp_seconds;
99 guint64 timestamp_fraction;
100 guint64 timestamp_nseconds;
101 /*
102 guint8 cseq;
103 */
104
105 if (!gst_rtp_buffer_map (buf, GST_MAP_READWRITE, &rtp)) {
106 GST_ELEMENT_ERROR (self, STREAM, FAILED,
107 ("Failed to map RTP buffer"), (NULL));
108 return FALSE;
109 }
110
111 /* Check if the ONVIF RTP extension is present in the packet */
112 if (!gst_rtp_buffer_get_extension_data (&rtp, &bits, (gpointer) & data,
113 &wordlen))
114 goto out;
115
116 if (bits != EXTENSION_ID || wordlen != EXTENSION_SIZE)
117 goto out;
118
119 timestamp_seconds = GST_READ_UINT32_BE (data);
120 timestamp_fraction = GST_READ_UINT32_BE (data + 4);
121 timestamp_nseconds =
122 (timestamp_fraction * G_GINT64_CONSTANT (1000000000)) >> 32;
123
124 if (timestamp_seconds == G_MAXUINT32 && timestamp_fraction == G_MAXUINT32) {
125 GST_BUFFER_PTS (buf) = GST_CLOCK_TIME_NONE;
126 } else {
127 GST_BUFFER_PTS (buf) =
128 timestamp_seconds * GST_SECOND + timestamp_nseconds * GST_NSECOND;
129 }
130
131 flags = GST_READ_UINT8 (data + 8);
132 /* cseq = GST_READ_UINT8 (data + 9); TODO */
133
134 /* C */
135 if (flags & (1 << 7))
136 GST_BUFFER_FLAG_UNSET (buf, GST_BUFFER_FLAG_DELTA_UNIT);
137 else
138 GST_BUFFER_FLAG_SET (buf, GST_BUFFER_FLAG_DELTA_UNIT);
139
140 /* E */
141 /* if (flags & (1 << 6)); TODO */
142
143 /* D */
144 if (flags & (1 << 5))
145 GST_BUFFER_FLAG_SET (buf, GST_BUFFER_FLAG_DISCONT);
146 else
147 GST_BUFFER_FLAG_UNSET (buf, GST_BUFFER_FLAG_DISCONT);
148
149 /* T */
150 if (flags & (1 << 4))
151 *send_eos = TRUE;
152
153 out:
154 gst_rtp_buffer_unmap (&rtp);
155 return TRUE;
156 }
157
158 static GstFlowReturn
gst_rtp_onvif_parse_chain(GstPad * pad,GstObject * parent,GstBuffer * buf)159 gst_rtp_onvif_parse_chain (GstPad * pad, GstObject * parent, GstBuffer * buf)
160 {
161 GstRtpOnvifParse *self = GST_RTP_ONVIF_PARSE (parent);
162 GstFlowReturn ret;
163 gboolean send_eos = FALSE;
164
165 if (!handle_buffer (self, buf, &send_eos)) {
166 gst_buffer_unref (buf);
167 return GST_FLOW_ERROR;
168 }
169
170 ret = gst_pad_push (self->srcpad, buf);
171
172 if (ret == GST_FLOW_OK && send_eos) {
173 GstEvent *event;
174
175 event = gst_event_new_eos ();
176 gst_pad_push_event (self->srcpad, event);
177 ret = GST_FLOW_EOS;
178 }
179
180 return ret;
181 }
182