1 /* GStreamer
2 * Copyright (C) <2005> 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 #ifdef HAVE_CONFIG_H
21 # include "config.h"
22 #endif
23
24 #include <gst/rtp/gstrtpbuffer.h>
25
26 #include <string.h>
27 #include "gstrtpelements.h"
28 #include "gstrtpmp2tdepay.h"
29 #include "gstrtputils.h"
30
31 /* RtpMP2TDepay signals and args */
32 enum
33 {
34 /* FILL ME */
35 LAST_SIGNAL
36 };
37
38 #define DEFAULT_SKIP_FIRST_BYTES 0
39
40 enum
41 {
42 PROP_0,
43 PROP_SKIP_FIRST_BYTES
44 };
45
46 static GstStaticPadTemplate gst_rtp_mp2t_depay_src_template =
47 GST_STATIC_PAD_TEMPLATE ("src",
48 GST_PAD_SRC,
49 GST_PAD_ALWAYS,
50 GST_STATIC_CAPS ("video/mpegts,"
51 "packetsize=(int)188," "systemstream=(boolean)true")
52 );
53
54 static GstStaticPadTemplate gst_rtp_mp2t_depay_sink_template =
55 GST_STATIC_PAD_TEMPLATE ("sink",
56 GST_PAD_SINK,
57 GST_PAD_ALWAYS,
58 GST_STATIC_CAPS ("application/x-rtp, "
59 "media = (string) \"video\", "
60 "clock-rate = (int) [1, MAX ], "
61 "encoding-name = (string) { MP2T, MP2T-ES } ;"
62 /* All optional parameters
63 *
64 * "profile-level-id=[1,MAX]"
65 * "config="
66 */
67 "application/x-rtp, "
68 "media = (string) \"video\", "
69 "payload = (int) " GST_RTP_PAYLOAD_MP2T_STRING ", "
70 "clock-rate = (int) [1, MAX ]")
71 );
72
73 G_DEFINE_TYPE (GstRtpMP2TDepay, gst_rtp_mp2t_depay,
74 GST_TYPE_RTP_BASE_DEPAYLOAD);
75 GST_ELEMENT_REGISTER_DEFINE_WITH_CODE (rtpmp2tdepay, "rtpmp2tdepay",
76 GST_RANK_SECONDARY, GST_TYPE_RTP_MP2T_DEPAY, rtp_element_init (plugin));
77
78 static gboolean gst_rtp_mp2t_depay_setcaps (GstRTPBaseDepayload * depayload,
79 GstCaps * caps);
80 static GstBuffer *gst_rtp_mp2t_depay_process (GstRTPBaseDepayload * depayload,
81 GstRTPBuffer * rtp);
82
83 static void gst_rtp_mp2t_depay_set_property (GObject * object, guint prop_id,
84 const GValue * value, GParamSpec * pspec);
85 static void gst_rtp_mp2t_depay_get_property (GObject * object, guint prop_id,
86 GValue * value, GParamSpec * pspec);
87
88 static void
gst_rtp_mp2t_depay_class_init(GstRtpMP2TDepayClass * klass)89 gst_rtp_mp2t_depay_class_init (GstRtpMP2TDepayClass * klass)
90 {
91 GObjectClass *gobject_class;
92 GstElementClass *gstelement_class;
93 GstRTPBaseDepayloadClass *gstrtpbasedepayload_class;
94
95 gobject_class = (GObjectClass *) klass;
96 gstelement_class = (GstElementClass *) klass;
97 gstrtpbasedepayload_class = (GstRTPBaseDepayloadClass *) klass;
98
99 gstrtpbasedepayload_class->process_rtp_packet = gst_rtp_mp2t_depay_process;
100 gstrtpbasedepayload_class->set_caps = gst_rtp_mp2t_depay_setcaps;
101
102 gobject_class->set_property = gst_rtp_mp2t_depay_set_property;
103 gobject_class->get_property = gst_rtp_mp2t_depay_get_property;
104
105 gst_element_class_add_static_pad_template (gstelement_class,
106 &gst_rtp_mp2t_depay_src_template);
107 gst_element_class_add_static_pad_template (gstelement_class,
108 &gst_rtp_mp2t_depay_sink_template);
109
110 gst_element_class_set_static_metadata (gstelement_class,
111 "RTP MPEG Transport Stream depayloader", "Codec/Depayloader/Network/RTP",
112 "Extracts MPEG2 TS from RTP packets (RFC 2250)",
113 "Wim Taymans <wim.taymans@gmail.com>, "
114 "Thijs Vermeir <thijs.vermeir@barco.com>");
115
116 g_object_class_install_property (gobject_class, PROP_SKIP_FIRST_BYTES,
117 g_param_spec_uint ("skip-first-bytes",
118 "Skip first bytes",
119 "The amount of bytes that need to be skipped at the beginning of the payload",
120 0, G_MAXUINT, 0, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
121
122 }
123
124 static void
gst_rtp_mp2t_depay_init(GstRtpMP2TDepay * rtpmp2tdepay)125 gst_rtp_mp2t_depay_init (GstRtpMP2TDepay * rtpmp2tdepay)
126 {
127 rtpmp2tdepay->skip_first_bytes = DEFAULT_SKIP_FIRST_BYTES;
128 }
129
130 static gboolean
gst_rtp_mp2t_depay_setcaps(GstRTPBaseDepayload * depayload,GstCaps * caps)131 gst_rtp_mp2t_depay_setcaps (GstRTPBaseDepayload * depayload, GstCaps * caps)
132 {
133 GstCaps *srccaps;
134 GstStructure *structure;
135 gint clock_rate;
136 gboolean res;
137
138 structure = gst_caps_get_structure (caps, 0);
139 if (!gst_structure_get_int (structure, "clock-rate", &clock_rate))
140 clock_rate = 90000; /* default */
141 depayload->clock_rate = clock_rate;
142
143 srccaps = gst_caps_new_simple ("video/mpegts",
144 "packetsize", G_TYPE_INT, 188,
145 "systemstream", G_TYPE_BOOLEAN, TRUE, NULL);
146 res = gst_pad_set_caps (GST_RTP_BASE_DEPAYLOAD_SRCPAD (depayload), srccaps);
147 gst_caps_unref (srccaps);
148
149 return res;
150 }
151
152 static GstBuffer *
gst_rtp_mp2t_depay_process(GstRTPBaseDepayload * depayload,GstRTPBuffer * rtp)153 gst_rtp_mp2t_depay_process (GstRTPBaseDepayload * depayload, GstRTPBuffer * rtp)
154 {
155 GstRtpMP2TDepay *rtpmp2tdepay;
156 GstBuffer *outbuf;
157 gint payload_len, leftover;
158
159 rtpmp2tdepay = GST_RTP_MP2T_DEPAY (depayload);
160
161 payload_len = gst_rtp_buffer_get_payload_len (rtp);
162
163 if (G_UNLIKELY (payload_len <= rtpmp2tdepay->skip_first_bytes))
164 goto empty_packet;
165
166 payload_len -= rtpmp2tdepay->skip_first_bytes;
167
168 /* RFC 2250
169 *
170 * 2. Encapsulation of MPEG System and Transport Streams
171 *
172 * For MPEG2 Transport Streams the RTP payload will contain an integral
173 * number of MPEG transport packets.
174 */
175 leftover = payload_len % 188;
176 if (G_UNLIKELY (leftover)) {
177 GST_WARNING ("We don't have an integral number of buffers (leftover: %d)",
178 leftover);
179
180 payload_len -= leftover;
181 }
182
183 outbuf =
184 gst_rtp_buffer_get_payload_subbuffer (rtp,
185 rtpmp2tdepay->skip_first_bytes, payload_len);
186
187 if (outbuf) {
188 GST_DEBUG ("gst_rtp_mp2t_depay_chain: pushing buffer of size %"
189 G_GSIZE_FORMAT, gst_buffer_get_size (outbuf));
190
191 gst_rtp_drop_meta (GST_ELEMENT_CAST (depayload), outbuf, 0);
192 }
193
194 return outbuf;
195
196 /* ERRORS */
197 empty_packet:
198 {
199 GST_ELEMENT_WARNING (rtpmp2tdepay, STREAM, DECODE,
200 (NULL), ("Packet was empty"));
201 return NULL;
202 }
203 }
204
205 static void
gst_rtp_mp2t_depay_set_property(GObject * object,guint prop_id,const GValue * value,GParamSpec * pspec)206 gst_rtp_mp2t_depay_set_property (GObject * object, guint prop_id,
207 const GValue * value, GParamSpec * pspec)
208 {
209 GstRtpMP2TDepay *rtpmp2tdepay;
210
211 rtpmp2tdepay = GST_RTP_MP2T_DEPAY (object);
212
213 switch (prop_id) {
214 case PROP_SKIP_FIRST_BYTES:
215 rtpmp2tdepay->skip_first_bytes = g_value_get_uint (value);
216 break;
217 default:
218 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
219 break;
220 }
221 }
222
223 static void
gst_rtp_mp2t_depay_get_property(GObject * object,guint prop_id,GValue * value,GParamSpec * pspec)224 gst_rtp_mp2t_depay_get_property (GObject * object, guint prop_id,
225 GValue * value, GParamSpec * pspec)
226 {
227 GstRtpMP2TDepay *rtpmp2tdepay;
228
229 rtpmp2tdepay = GST_RTP_MP2T_DEPAY (object);
230
231 switch (prop_id) {
232 case PROP_SKIP_FIRST_BYTES:
233 g_value_set_uint (value, rtpmp2tdepay->skip_first_bytes);
234 break;
235 default:
236 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
237 break;
238 }
239 }
240