1 /* GStreamer RTP KLV Payloader
2 * Copyright (C) 2014-2015 Tim-Philipp Müller <tim@centricular.com>>
3 * Copyright (C) 2014-2015 Centricular Ltd
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Library General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
9 *
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Library General Public License for more details.
14 *
15 * You should have received a copy of the GNU Library General Public
16 * License along with this library; if not, write to the
17 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
18 * Boston, MA 02110-1301, USA.
19 */
20
21 /**
22 * SECTION:element-rtpklvpay
23 * @title: rtpklvpay
24 * @see_also: rtpklvdepay
25 *
26 * Payloads KLV metadata into RTP packets according to RFC 6597.
27 * For detailed information see: http://tools.ietf.org/html/rfc6597
28 *
29 * ## Example pipeline
30 * |[
31 * gst-launch-1.0 filesrc location=video-with-klv.ts ! tsdemux ! rtpklvpay ! udpsink
32 * ]| This example pipeline will payload an RTP KLV stream extracted from an
33 * MPEG-TS stream and send it via UDP to an RTP receiver.
34 *
35 */
36 #ifdef HAVE_CONFIG_H
37 #include "config.h"
38 #endif
39
40 #include "gstrtpelements.h"
41 #include "gstrtpklvpay.h"
42 #include "gstrtputils.h"
43
44 #include <string.h>
45
46 GST_DEBUG_CATEGORY_STATIC (klvpay_debug);
47 #define GST_CAT_DEFAULT (klvpay_debug)
48
49 static GstStaticPadTemplate src_template = GST_STATIC_PAD_TEMPLATE ("src",
50 GST_PAD_SRC,
51 GST_PAD_ALWAYS,
52 GST_STATIC_CAPS ("application/x-rtp, "
53 "media = (string) application, clock-rate = (int) [1, MAX], "
54 "encoding-name = (string) SMPTE336M")
55 );
56
57 static GstStaticPadTemplate sink_template = GST_STATIC_PAD_TEMPLATE ("sink",
58 GST_PAD_SINK,
59 GST_PAD_ALWAYS,
60 GST_STATIC_CAPS ("meta/x-klv, parsed = (bool) true"));
61
62 #define gst_rtp_klv_pay_parent_class parent_class
63 G_DEFINE_TYPE (GstRtpKlvPay, gst_rtp_klv_pay, GST_TYPE_RTP_BASE_PAYLOAD);
64 GST_ELEMENT_REGISTER_DEFINE_WITH_CODE (rtpklvpay, "rtpklvpay",
65 GST_RANK_SECONDARY, GST_TYPE_RTP_KLV_PAY, rtp_element_init (plugin));
66
67 static gboolean gst_rtp_klv_pay_setcaps (GstRTPBasePayload * pay,
68 GstCaps * caps);
69 static GstFlowReturn gst_rtp_klv_pay_handle_buffer (GstRTPBasePayload * pay,
70 GstBuffer * buf);
71
72 static void
gst_rtp_klv_pay_class_init(GstRtpKlvPayClass * klass)73 gst_rtp_klv_pay_class_init (GstRtpKlvPayClass * klass)
74 {
75 GstElementClass *element_class = (GstElementClass *) klass;
76 GstRTPBasePayloadClass *rtpbasepay_class;
77
78 GST_DEBUG_CATEGORY_INIT (klvpay_debug, "klvpay", 0, "RTP KLV Payloader");
79
80 gst_element_class_add_static_pad_template (element_class, &src_template);
81 gst_element_class_add_static_pad_template (element_class, &sink_template);
82
83 gst_element_class_set_static_metadata (element_class,
84 "RTP KLV Payloader", "Codec/Payloader/Network/RTP",
85 "Payloads KLV (SMPTE ST 336) metadata as RTP packets",
86 "Tim-Philipp Müller <tim@centricular.com>");
87
88 rtpbasepay_class = (GstRTPBasePayloadClass *) klass;
89
90 rtpbasepay_class->set_caps = gst_rtp_klv_pay_setcaps;
91 rtpbasepay_class->handle_buffer = gst_rtp_klv_pay_handle_buffer;
92 }
93
94 static void
gst_rtp_klv_pay_init(GstRtpKlvPay * klvpay)95 gst_rtp_klv_pay_init (GstRtpKlvPay * klvpay)
96 {
97 /* nothing to do here yet */
98 }
99
100 static gboolean
gst_rtp_klv_pay_setcaps(GstRTPBasePayload * pay,GstCaps * caps)101 gst_rtp_klv_pay_setcaps (GstRTPBasePayload * pay, GstCaps * caps)
102 {
103 /* FIXME: allow other clock rates */
104 gst_rtp_base_payload_set_options (pay, "application", TRUE, "SMPTE336M",
105 90000);
106
107 return gst_rtp_base_payload_set_outcaps (pay, NULL);
108 }
109
110 static GstFlowReturn
gst_rtp_klv_pay_handle_buffer(GstRTPBasePayload * basepayload,GstBuffer * buf)111 gst_rtp_klv_pay_handle_buffer (GstRTPBasePayload * basepayload, GstBuffer * buf)
112 {
113 GstFlowReturn ret = GST_FLOW_OK;
114 GstBufferList *list = NULL;
115 GstRtpKlvPay *pay;
116 GstMapInfo map;
117 GstBuffer *outbuf = NULL;
118 gsize offset;
119 guint mtu, rtp_header_size, max_payload_size;
120
121 pay = GST_RTP_KLV_PAY (basepayload);
122 mtu = GST_RTP_BASE_PAYLOAD_MTU (basepayload);
123
124 rtp_header_size = gst_rtp_buffer_calc_header_len (0);
125 max_payload_size = mtu - rtp_header_size;
126
127 gst_buffer_map (buf, &map, GST_MAP_READ);
128
129 if (map.size == 0)
130 goto done;
131
132 /* KLV coding shall use and only use a fixed 16-byte SMPTE-administered
133 * Universal Label, according to SMPTE 298M as Key (Rec. ITU R-BT.1653-1) */
134 if (map.size < 16 || GST_READ_UINT32_BE (map.data) != 0x060E2B34)
135 goto bad_input;
136
137 if (map.size > max_payload_size)
138 list = gst_buffer_list_new ();
139
140 GST_LOG_OBJECT (pay, "%" G_GSIZE_FORMAT " bytes of data to payload",
141 map.size);
142
143 offset = 0;
144 while (offset < map.size) {
145 GstBuffer *payloadbuf;
146 GstRTPBuffer rtp = { NULL };
147 guint payload_size;
148 guint bytes_left;
149
150 bytes_left = map.size - offset;
151 payload_size = MIN (bytes_left, max_payload_size);
152
153 outbuf = gst_rtp_base_payload_allocate_output_buffer (basepayload, 0, 0, 0);
154
155 if (payload_size == bytes_left) {
156 GST_LOG_OBJECT (pay, "last packet of KLV unit");
157 gst_rtp_buffer_map (outbuf, GST_MAP_WRITE, &rtp);
158 gst_rtp_buffer_set_marker (&rtp, 1);
159 gst_rtp_buffer_unmap (&rtp);
160 }
161
162 GST_LOG_OBJECT (pay, "packet with payload size %u", payload_size);
163
164 gst_rtp_copy_meta (GST_ELEMENT_CAST (pay), outbuf, buf, 0);
165
166 payloadbuf = gst_buffer_copy_region (buf, GST_BUFFER_COPY_MEMORY,
167 offset, payload_size);
168
169 /* join rtp header + payload memory parts */
170 outbuf = gst_buffer_append (outbuf, payloadbuf);
171
172 GST_BUFFER_PTS (outbuf) = GST_BUFFER_PTS (buf);
173 GST_BUFFER_DTS (outbuf) = GST_BUFFER_DTS (buf);
174
175 /* and add to list */
176 if (list != NULL)
177 gst_buffer_list_insert (list, -1, outbuf);
178
179 offset += payload_size;
180 }
181
182 done:
183
184 gst_buffer_unmap (buf, &map);
185 gst_buffer_unref (buf);
186
187 if (list != NULL)
188 ret = gst_rtp_base_payload_push_list (basepayload, list);
189 else if (outbuf != NULL)
190 ret = gst_rtp_base_payload_push (basepayload, outbuf);
191
192 return ret;
193
194 /* ERRORS */
195 bad_input:
196 {
197 GST_ERROR_OBJECT (pay, "Input doesn't look like a KLV packet, ignoring");
198 goto done;
199 }
200 }
201