1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
|
/* GStreamer
* Copyright (C) <2006> Wim Taymans <wim.taymans@gmail.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <gst/rtp/gstrtpbuffer.h>
#include <gst/video/video.h>
#include <string.h>
#include "gstrtpelements.h"
#include "gstrtpmpvdepay.h"
#include "gstrtputils.h"
GST_DEBUG_CATEGORY_STATIC (rtpmpvdepay_debug);
#define GST_CAT_DEFAULT (rtpmpvdepay_debug)
/* FIXME, we set the mpeg version to 2, we should ideally be looking at contents
* of the stream to figure out the version */
static GstStaticPadTemplate gst_rtp_mpv_depay_src_template =
GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS
("video/mpeg, mpegversion = (int) 2, systemstream = (boolean) FALSE")
);
static GstStaticPadTemplate gst_rtp_mpv_depay_sink_template =
GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("application/x-rtp, "
"media = (string) \"video\", "
"clock-rate = (int) 90000, " "encoding-name = (string) \"MPV\";"
"application/x-rtp, "
"media = (string) \"video\", "
"payload = (int) " GST_RTP_PAYLOAD_MPV_STRING ", "
"clock-rate = (int) 90000")
);
G_DEFINE_TYPE (GstRtpMPVDepay, gst_rtp_mpv_depay, GST_TYPE_RTP_BASE_DEPAYLOAD);
GST_ELEMENT_REGISTER_DEFINE_WITH_CODE (rtpmpvdepay, "rtpmpvdepay",
GST_RANK_SECONDARY, GST_TYPE_RTP_MPV_DEPAY, rtp_element_init (plugin));
static gboolean gst_rtp_mpv_depay_setcaps (GstRTPBaseDepayload * depayload,
GstCaps * caps);
static GstBuffer *gst_rtp_mpv_depay_process (GstRTPBaseDepayload * depayload,
GstRTPBuffer * rtp);
static void
gst_rtp_mpv_depay_class_init (GstRtpMPVDepayClass * klass)
{
GstElementClass *gstelement_class;
GstRTPBaseDepayloadClass *gstrtpbasedepayload_class;
gstelement_class = (GstElementClass *) klass;
gstrtpbasedepayload_class = (GstRTPBaseDepayloadClass *) klass;
gst_element_class_add_static_pad_template (gstelement_class,
&gst_rtp_mpv_depay_src_template);
gst_element_class_add_static_pad_template (gstelement_class,
&gst_rtp_mpv_depay_sink_template);
gst_element_class_set_static_metadata (gstelement_class,
"RTP MPEG video depayloader", "Codec/Depayloader/Network/RTP",
"Extracts MPEG video from RTP packets (RFC 2250)",
"Wim Taymans <wim.taymans@gmail.com>");
gstrtpbasedepayload_class->set_caps = gst_rtp_mpv_depay_setcaps;
gstrtpbasedepayload_class->process_rtp_packet = gst_rtp_mpv_depay_process;
GST_DEBUG_CATEGORY_INIT (rtpmpvdepay_debug, "rtpmpvdepay", 0,
"MPEG Video RTP Depayloader");
}
static void
gst_rtp_mpv_depay_init (GstRtpMPVDepay * rtpmpvdepay)
{
}
static gboolean
gst_rtp_mpv_depay_setcaps (GstRTPBaseDepayload * depayload, GstCaps * caps)
{
GstStructure *structure;
gint clock_rate;
GstCaps *outcaps;
gboolean res;
structure = gst_caps_get_structure (caps, 0);
if (!gst_structure_get_int (structure, "clock-rate", &clock_rate))
clock_rate = 90000; /* default */
depayload->clock_rate = clock_rate;
outcaps = gst_caps_new_simple ("video/mpeg",
"mpegversion", G_TYPE_INT, 2,
"systemstream", G_TYPE_BOOLEAN, FALSE, NULL);
res = gst_pad_set_caps (depayload->srcpad, outcaps);
gst_caps_unref (outcaps);
return res;
}
static GstBuffer *
gst_rtp_mpv_depay_process (GstRTPBaseDepayload * depayload, GstRTPBuffer * rtp)
{
GstRtpMPVDepay *rtpmpvdepay;
GstBuffer *outbuf = NULL;
rtpmpvdepay = GST_RTP_MPV_DEPAY (depayload);
{
gint payload_len, payload_header;
guint8 *payload;
guint8 T;
payload_len = gst_rtp_buffer_get_payload_len (rtp);
payload = gst_rtp_buffer_get_payload (rtp);
payload_header = 0;
if (payload_len <= 4)
goto empty_packet;
/* 3.4 MPEG Video-specific header
*
* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | MBZ |T| TR | |N|S|B|E| P | | BFC | | FFC |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* AN FBV FFV
*/
T = (payload[0] & 0x04);
payload_len -= 4;
payload_header += 4;
payload += 4;
if (T) {
/*
* 3.4.1 MPEG-2 Video-specific header extension
*
* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* |X|E|f_[0,0]|f_[0,1]|f_[1,0]|f_[1,1]| DC| PS|T|P|C|Q|V|A|R|H|G|D|
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
if (payload_len <= 4)
goto empty_packet;
payload_len -= 4;
payload_header += 4;
payload += 4;
}
outbuf = gst_rtp_buffer_get_payload_subbuffer (rtp, payload_header, -1);
if (outbuf) {
GST_DEBUG_OBJECT (rtpmpvdepay,
"gst_rtp_mpv_depay_chain: pushing buffer of size %" G_GSIZE_FORMAT,
gst_buffer_get_size (outbuf));
gst_rtp_drop_non_video_meta (rtpmpvdepay, outbuf);
}
}
return outbuf;
/* ERRORS */
empty_packet:
{
GST_ELEMENT_WARNING (rtpmpvdepay, STREAM, DECODE,
(NULL), ("Empty payload."));
return NULL;
}
}
|
