1 /* gstrtpvp8depay.c - Source for GstRtpVP8Depay
2 * Copyright (C) 2011 Sjoerd Simons <sjoerd@luon.net>
3 * Copyright (C) 2011 Collabora Ltd.
4 * Contact: Youness Alaoui <youness.alaoui@collabora.co.uk>
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21 #ifdef HAVE_CONFIG_H
22 # include "config.h"
23 #endif
24
25 #include "gstrtpvp8depay.h"
26 #include "gstrtputils.h"
27
28 #include <gst/video/video.h>
29
30 #include <stdio.h>
31
32 GST_DEBUG_CATEGORY_STATIC (gst_rtp_vp8_depay_debug);
33 #define GST_CAT_DEFAULT gst_rtp_vp8_depay_debug
34
35 static void gst_rtp_vp8_depay_dispose (GObject * object);
36 static GstBuffer *gst_rtp_vp8_depay_process (GstRTPBaseDepayload * depayload,
37 GstRTPBuffer * rtp);
38 static GstStateChangeReturn gst_rtp_vp8_depay_change_state (GstElement *
39 element, GstStateChange transition);
40 static gboolean gst_rtp_vp8_depay_handle_event (GstRTPBaseDepayload * depay,
41 GstEvent * event);
42
43 G_DEFINE_TYPE (GstRtpVP8Depay, gst_rtp_vp8_depay, GST_TYPE_RTP_BASE_DEPAYLOAD);
44
45 static GstStaticPadTemplate gst_rtp_vp8_depay_src_template =
46 GST_STATIC_PAD_TEMPLATE ("src",
47 GST_PAD_SRC,
48 GST_PAD_ALWAYS,
49 GST_STATIC_CAPS ("video/x-vp8"));
50
51 static GstStaticPadTemplate gst_rtp_vp8_depay_sink_template =
52 GST_STATIC_PAD_TEMPLATE ("sink",
53 GST_PAD_SINK,
54 GST_PAD_ALWAYS,
55 GST_STATIC_CAPS ("application/x-rtp, "
56 "clock-rate = (int) 90000,"
57 "media = (string) \"video\","
58 "encoding-name = (string) { \"VP8\", \"VP8-DRAFT-IETF-01\" }"));
59
60 static void
gst_rtp_vp8_depay_init(GstRtpVP8Depay * self)61 gst_rtp_vp8_depay_init (GstRtpVP8Depay * self)
62 {
63 self->adapter = gst_adapter_new ();
64 self->started = FALSE;
65 }
66
67 static void
gst_rtp_vp8_depay_class_init(GstRtpVP8DepayClass * gst_rtp_vp8_depay_class)68 gst_rtp_vp8_depay_class_init (GstRtpVP8DepayClass * gst_rtp_vp8_depay_class)
69 {
70 GObjectClass *object_class = G_OBJECT_CLASS (gst_rtp_vp8_depay_class);
71 GstElementClass *element_class = GST_ELEMENT_CLASS (gst_rtp_vp8_depay_class);
72 GstRTPBaseDepayloadClass *depay_class =
73 (GstRTPBaseDepayloadClass *) (gst_rtp_vp8_depay_class);
74
75
76 gst_element_class_add_static_pad_template (element_class,
77 &gst_rtp_vp8_depay_sink_template);
78 gst_element_class_add_static_pad_template (element_class,
79 &gst_rtp_vp8_depay_src_template);
80
81 gst_element_class_set_static_metadata (element_class, "RTP VP8 depayloader",
82 "Codec/Depayloader/Network/RTP",
83 "Extracts VP8 video from RTP packets)",
84 "Sjoerd Simons <sjoerd@luon.net>");
85
86 object_class->dispose = gst_rtp_vp8_depay_dispose;
87
88 element_class->change_state = gst_rtp_vp8_depay_change_state;
89
90 depay_class->process_rtp_packet = gst_rtp_vp8_depay_process;
91 depay_class->handle_event = gst_rtp_vp8_depay_handle_event;
92
93 GST_DEBUG_CATEGORY_INIT (gst_rtp_vp8_depay_debug, "rtpvp8depay", 0,
94 "VP8 Video RTP Depayloader");
95 }
96
97 static void
gst_rtp_vp8_depay_dispose(GObject * object)98 gst_rtp_vp8_depay_dispose (GObject * object)
99 {
100 GstRtpVP8Depay *self = GST_RTP_VP8_DEPAY (object);
101
102 if (self->adapter != NULL)
103 g_object_unref (self->adapter);
104 self->adapter = NULL;
105
106 /* release any references held by the object here */
107
108 if (G_OBJECT_CLASS (gst_rtp_vp8_depay_parent_class)->dispose)
109 G_OBJECT_CLASS (gst_rtp_vp8_depay_parent_class)->dispose (object);
110 }
111
112 static GstBuffer *
gst_rtp_vp8_depay_process(GstRTPBaseDepayload * depay,GstRTPBuffer * rtp)113 gst_rtp_vp8_depay_process (GstRTPBaseDepayload * depay, GstRTPBuffer * rtp)
114 {
115 GstRtpVP8Depay *self = GST_RTP_VP8_DEPAY (depay);
116 GstBuffer *payload;
117 guint8 *data;
118 guint hdrsize;
119 guint size;
120
121 if (G_UNLIKELY (GST_BUFFER_IS_DISCONT (rtp->buffer))) {
122 GST_LOG_OBJECT (self, "Discontinuity, flushing adapter");
123 gst_adapter_clear (self->adapter);
124 self->started = FALSE;
125 }
126
127 size = gst_rtp_buffer_get_payload_len (rtp);
128
129 /* At least one header and one vp8 byte */
130 if (G_UNLIKELY (size < 2))
131 goto too_small;
132
133 data = gst_rtp_buffer_get_payload (rtp);
134
135 if (G_UNLIKELY (!self->started)) {
136 /* Check if this is the start of a VP8 frame, otherwise bail */
137 /* S=1 and PartID= 0 */
138 if ((data[0] & 0x17) != 0x10)
139 goto done;
140
141 self->started = TRUE;
142 }
143
144 hdrsize = 1;
145 /* Check X optional header */
146 if ((data[0] & 0x80) != 0) {
147 hdrsize++;
148 /* Check I optional header */
149 if ((data[1] & 0x80) != 0) {
150 if (G_UNLIKELY (size < 3))
151 goto too_small;
152 hdrsize++;
153 /* Check for 16 bits PictureID */
154 if ((data[2] & 0x80) != 0)
155 hdrsize++;
156 }
157 /* Check L optional header */
158 if ((data[1] & 0x40) != 0)
159 hdrsize++;
160 /* Check T or K optional headers */
161 if ((data[1] & 0x20) != 0 || (data[1] & 0x10) != 0)
162 hdrsize++;
163 }
164 GST_DEBUG_OBJECT (depay, "hdrsize %u, size %u", hdrsize, size);
165
166 if (G_UNLIKELY (hdrsize >= size))
167 goto too_small;
168
169 payload = gst_rtp_buffer_get_payload_subbuffer (rtp, hdrsize, -1);
170 gst_adapter_push (self->adapter, payload);
171
172 /* Marker indicates that it was the last rtp packet for this frame */
173 if (gst_rtp_buffer_get_marker (rtp)) {
174 GstBuffer *out;
175 guint8 header[10];
176
177 if (gst_adapter_available (self->adapter) < 10)
178 goto too_small;
179 gst_adapter_copy (self->adapter, &header, 0, 10);
180
181 out = gst_adapter_take_buffer (self->adapter,
182 gst_adapter_available (self->adapter));
183
184 self->started = FALSE;
185
186 /* mark keyframes */
187 out = gst_buffer_make_writable (out);
188 /* Filter away all metas that are not sensible to copy */
189 gst_rtp_drop_non_video_meta (self, out);
190 if ((header[0] & 0x01)) {
191 GST_BUFFER_FLAG_SET (out, GST_BUFFER_FLAG_DELTA_UNIT);
192
193 if (!self->caps_sent) {
194 gst_buffer_unref (out);
195 out = NULL;
196 GST_INFO_OBJECT (self, "Dropping inter-frame before intra-frame");
197 gst_pad_push_event (GST_RTP_BASE_DEPAYLOAD_SINKPAD (depay),
198 gst_video_event_new_upstream_force_key_unit (GST_CLOCK_TIME_NONE,
199 TRUE, 0));
200 }
201 } else {
202 guint profile, width, height;
203
204 GST_BUFFER_FLAG_UNSET (out, GST_BUFFER_FLAG_DELTA_UNIT);
205
206 profile = (header[0] & 0x0e) >> 1;
207 width = GST_READ_UINT16_LE (header + 6) & 0x3fff;
208 height = GST_READ_UINT16_LE (header + 8) & 0x3fff;
209
210 if (G_UNLIKELY (self->last_width != width ||
211 self->last_height != height || self->last_profile != profile)) {
212 gchar profile_str[3];
213 GstCaps *srccaps;
214
215 snprintf (profile_str, 3, "%u", profile);
216 srccaps = gst_caps_new_simple ("video/x-vp8",
217 "framerate", GST_TYPE_FRACTION, 0, 1,
218 "height", G_TYPE_INT, height,
219 "width", G_TYPE_INT, width,
220 "profile", G_TYPE_STRING, profile_str, NULL);
221
222 gst_pad_set_caps (GST_RTP_BASE_DEPAYLOAD_SRCPAD (depay), srccaps);
223 gst_caps_unref (srccaps);
224
225 self->caps_sent = TRUE;
226 self->last_width = width;
227 self->last_height = height;
228 self->last_profile = profile;
229 }
230 }
231
232 return out;
233 }
234
235 done:
236 return NULL;
237
238 too_small:
239 GST_LOG_OBJECT (self, "Invalid rtp packet (too small), ignoring");
240 gst_adapter_clear (self->adapter);
241 self->started = FALSE;
242
243 goto done;
244 }
245
246 static GstStateChangeReturn
gst_rtp_vp8_depay_change_state(GstElement * element,GstStateChange transition)247 gst_rtp_vp8_depay_change_state (GstElement * element, GstStateChange transition)
248 {
249 GstRtpVP8Depay *self = GST_RTP_VP8_DEPAY (element);
250
251 switch (transition) {
252 case GST_STATE_CHANGE_READY_TO_PAUSED:
253 self->last_profile = -1;
254 self->last_height = -1;
255 self->last_width = -1;
256 self->caps_sent = FALSE;
257 break;
258 default:
259 break;
260 }
261
262 return
263 GST_ELEMENT_CLASS (gst_rtp_vp8_depay_parent_class)->change_state (element,
264 transition);
265 }
266
267 static gboolean
gst_rtp_vp8_depay_handle_event(GstRTPBaseDepayload * depay,GstEvent * event)268 gst_rtp_vp8_depay_handle_event (GstRTPBaseDepayload * depay, GstEvent * event)
269 {
270 GstRtpVP8Depay *self = GST_RTP_VP8_DEPAY (depay);
271
272 switch (GST_EVENT_TYPE (event)) {
273 case GST_EVENT_FLUSH_STOP:
274 self->last_profile = -1;
275 self->last_height = -1;
276 self->last_width = -1;
277 break;
278 default:
279 break;
280 }
281
282 return
283 GST_RTP_BASE_DEPAYLOAD_CLASS
284 (gst_rtp_vp8_depay_parent_class)->handle_event (depay, event);
285 }
286
287 gboolean
gst_rtp_vp8_depay_plugin_init(GstPlugin * plugin)288 gst_rtp_vp8_depay_plugin_init (GstPlugin * plugin)
289 {
290 return gst_element_register (plugin, "rtpvp8depay",
291 GST_RANK_MARGINAL, GST_TYPE_RTP_VP8_DEPAY);
292 }
293