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 "gstrtpmp2tdepay.h"
28 #include "gstrtputils.h"
29
30 /* RtpMP2TDepay signals and args */
31 enum
32 {
33 /* FILL ME */
34 LAST_SIGNAL
35 };
36
37 #define DEFAULT_SKIP_FIRST_BYTES 0
38
39 enum
40 {
41 PROP_0,
42 PROP_SKIP_FIRST_BYTES
43 };
44
45 static GstStaticPadTemplate gst_rtp_mp2t_depay_src_template =
46 GST_STATIC_PAD_TEMPLATE ("src",
47 GST_PAD_SRC,
48 GST_PAD_ALWAYS,
49 GST_STATIC_CAPS ("video/mpegts,"
50 "packetsize=(int)188," "systemstream=(boolean)true")
51 );
52
53 static GstStaticPadTemplate gst_rtp_mp2t_depay_sink_template =
54 GST_STATIC_PAD_TEMPLATE ("sink",
55 GST_PAD_SINK,
56 GST_PAD_ALWAYS,
57 GST_STATIC_CAPS ("application/x-rtp, "
58 "media = (string) \"video\", "
59 "clock-rate = (int) [1, MAX ], "
60 "encoding-name = (string) { MP2T, MP2T-ES } ;"
61 /* All optional parameters
62 *
63 * "profile-level-id=[1,MAX]"
64 * "config="
65 */
66 "application/x-rtp, "
67 "media = (string) \"video\", "
68 "payload = (int) " GST_RTP_PAYLOAD_MP2T_STRING ", "
69 "clock-rate = (int) [1, MAX ]")
70 );
71
72 G_DEFINE_TYPE (GstRtpMP2TDepay, gst_rtp_mp2t_depay,
73 GST_TYPE_RTP_BASE_DEPAYLOAD);
74
75 static gboolean gst_rtp_mp2t_depay_setcaps (GstRTPBaseDepayload * depayload,
76 GstCaps * caps);
77 static GstBuffer *gst_rtp_mp2t_depay_process (GstRTPBaseDepayload * depayload,
78 GstRTPBuffer * rtp);
79
80 static void gst_rtp_mp2t_depay_set_property (GObject * object, guint prop_id,
81 const GValue * value, GParamSpec * pspec);
82 static void gst_rtp_mp2t_depay_get_property (GObject * object, guint prop_id,
83 GValue * value, GParamSpec * pspec);
84
85 static void
gst_rtp_mp2t_depay_class_init(GstRtpMP2TDepayClass * klass)86 gst_rtp_mp2t_depay_class_init (GstRtpMP2TDepayClass * klass)
87 {
88 GObjectClass *gobject_class;
89 GstElementClass *gstelement_class;
90 GstRTPBaseDepayloadClass *gstrtpbasedepayload_class;
91
92 gobject_class = (GObjectClass *) klass;
93 gstelement_class = (GstElementClass *) klass;
94 gstrtpbasedepayload_class = (GstRTPBaseDepayloadClass *) klass;
95
96 gstrtpbasedepayload_class->process_rtp_packet = gst_rtp_mp2t_depay_process;
97 gstrtpbasedepayload_class->set_caps = gst_rtp_mp2t_depay_setcaps;
98
99 gobject_class->set_property = gst_rtp_mp2t_depay_set_property;
100 gobject_class->get_property = gst_rtp_mp2t_depay_get_property;
101
102 gst_element_class_add_static_pad_template (gstelement_class,
103 &gst_rtp_mp2t_depay_src_template);
104 gst_element_class_add_static_pad_template (gstelement_class,
105 &gst_rtp_mp2t_depay_sink_template);
106
107 gst_element_class_set_static_metadata (gstelement_class,
108 "RTP MPEG Transport Stream depayloader", "Codec/Depayloader/Network/RTP",
109 "Extracts MPEG2 TS from RTP packets (RFC 2250)",
110 "Wim Taymans <wim.taymans@gmail.com>, "
111 "Thijs Vermeir <thijs.vermeir@barco.com>");
112
113 g_object_class_install_property (gobject_class, PROP_SKIP_FIRST_BYTES,
114 g_param_spec_uint ("skip-first-bytes",
115 "Skip first bytes",
116 "The amount of bytes that need to be skipped at the beginning of the payload",
117 0, G_MAXUINT, 0, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
118
119 }
120
121 static void
gst_rtp_mp2t_depay_init(GstRtpMP2TDepay * rtpmp2tdepay)122 gst_rtp_mp2t_depay_init (GstRtpMP2TDepay * rtpmp2tdepay)
123 {
124 rtpmp2tdepay->skip_first_bytes = DEFAULT_SKIP_FIRST_BYTES;
125 }
126
127 static gboolean
gst_rtp_mp2t_depay_setcaps(GstRTPBaseDepayload * depayload,GstCaps * caps)128 gst_rtp_mp2t_depay_setcaps (GstRTPBaseDepayload * depayload, GstCaps * caps)
129 {
130 GstCaps *srccaps;
131 GstStructure *structure;
132 gint clock_rate;
133 gboolean res;
134
135 structure = gst_caps_get_structure (caps, 0);
136 if (!gst_structure_get_int (structure, "clock-rate", &clock_rate))
137 clock_rate = 90000; /* default */
138 depayload->clock_rate = clock_rate;
139
140 srccaps = gst_caps_new_simple ("video/mpegts",
141 "packetsize", G_TYPE_INT, 188,
142 "systemstream", G_TYPE_BOOLEAN, TRUE, NULL);
143 res = gst_pad_set_caps (GST_RTP_BASE_DEPAYLOAD_SRCPAD (depayload), srccaps);
144 gst_caps_unref (srccaps);
145
146 return res;
147 }
148
149 static GstBuffer *
gst_rtp_mp2t_depay_process(GstRTPBaseDepayload * depayload,GstRTPBuffer * rtp)150 gst_rtp_mp2t_depay_process (GstRTPBaseDepayload * depayload, GstRTPBuffer * rtp)
151 {
152 GstRtpMP2TDepay *rtpmp2tdepay;
153 GstBuffer *outbuf;
154 gint payload_len, leftover;
155
156 rtpmp2tdepay = GST_RTP_MP2T_DEPAY (depayload);
157
158 payload_len = gst_rtp_buffer_get_payload_len (rtp);
159
160 if (G_UNLIKELY (payload_len <= rtpmp2tdepay->skip_first_bytes))
161 goto empty_packet;
162
163 payload_len -= rtpmp2tdepay->skip_first_bytes;
164
165 /* RFC 2250
166 *
167 * 2. Encapsulation of MPEG System and Transport Streams
168 *
169 * For MPEG2 Transport Streams the RTP payload will contain an integral
170 * number of MPEG transport packets.
171 */
172 leftover = payload_len % 188;
173 if (G_UNLIKELY (leftover)) {
174 GST_WARNING ("We don't have an integral number of buffers (leftover: %d)",
175 leftover);
176
177 payload_len -= leftover;
178 }
179
180 outbuf =
181 gst_rtp_buffer_get_payload_subbuffer (rtp,
182 rtpmp2tdepay->skip_first_bytes, payload_len);
183
184 if (outbuf) {
185 GST_DEBUG ("gst_rtp_mp2t_depay_chain: pushing buffer of size %"
186 G_GSIZE_FORMAT, gst_buffer_get_size (outbuf));
187
188 gst_rtp_drop_meta (GST_ELEMENT_CAST (depayload), outbuf, 0);
189 }
190
191 return outbuf;
192
193 /* ERRORS */
194 empty_packet:
195 {
196 GST_ELEMENT_WARNING (rtpmp2tdepay, STREAM, DECODE,
197 (NULL), ("Packet was empty"));
198 return NULL;
199 }
200 }
201
202 static void
gst_rtp_mp2t_depay_set_property(GObject * object,guint prop_id,const GValue * value,GParamSpec * pspec)203 gst_rtp_mp2t_depay_set_property (GObject * object, guint prop_id,
204 const GValue * value, GParamSpec * pspec)
205 {
206 GstRtpMP2TDepay *rtpmp2tdepay;
207
208 rtpmp2tdepay = GST_RTP_MP2T_DEPAY (object);
209
210 switch (prop_id) {
211 case PROP_SKIP_FIRST_BYTES:
212 rtpmp2tdepay->skip_first_bytes = g_value_get_uint (value);
213 break;
214 default:
215 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
216 break;
217 }
218 }
219
220 static void
gst_rtp_mp2t_depay_get_property(GObject * object,guint prop_id,GValue * value,GParamSpec * pspec)221 gst_rtp_mp2t_depay_get_property (GObject * object, guint prop_id,
222 GValue * value, GParamSpec * pspec)
223 {
224 GstRtpMP2TDepay *rtpmp2tdepay;
225
226 rtpmp2tdepay = GST_RTP_MP2T_DEPAY (object);
227
228 switch (prop_id) {
229 case PROP_SKIP_FIRST_BYTES:
230 g_value_set_uint (value, rtpmp2tdepay->skip_first_bytes);
231 break;
232 default:
233 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
234 break;
235 }
236 }
237
238 gboolean
gst_rtp_mp2t_depay_plugin_init(GstPlugin * plugin)239 gst_rtp_mp2t_depay_plugin_init (GstPlugin * plugin)
240 {
241 return gst_element_register (plugin, "rtpmp2tdepay",
242 GST_RANK_SECONDARY, GST_TYPE_RTP_MP2T_DEPAY);
243 }
244