gstreamer/gst/rtp/gstrtpgstdepay.c

518 lines
13 KiB
C

/* GStreamer
* Copyright (C) <2010> 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 <string.h>
#include <stdlib.h>
#include "gstrtpgstdepay.h"
GST_DEBUG_CATEGORY_STATIC (rtpgstdepay_debug);
#define GST_CAT_DEFAULT (rtpgstdepay_debug)
static GstStaticPadTemplate gst_rtp_gst_depay_src_template =
GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS_ANY);
static GstStaticPadTemplate gst_rtp_gst_depay_sink_template =
GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("application/x-rtp, "
"media = (string) \"application\", "
"clock-rate = (int) 90000, " "encoding-name = (string) \"X-GST\"")
);
#define gst_rtp_gst_depay_parent_class parent_class
G_DEFINE_TYPE (GstRtpGSTDepay, gst_rtp_gst_depay, GST_TYPE_RTP_BASE_DEPAYLOAD);
static void gst_rtp_gst_depay_finalize (GObject * object);
static GstStateChangeReturn gst_rtp_gst_depay_change_state (GstElement *
element, GstStateChange transition);
static void gst_rtp_gst_depay_reset (GstRtpGSTDepay * rtpgstdepay);
static gboolean gst_rtp_gst_depay_setcaps (GstRTPBaseDepayload * depayload,
GstCaps * caps);
static GstBuffer *gst_rtp_gst_depay_process (GstRTPBaseDepayload * depayload,
GstBuffer * buf);
static void
gst_rtp_gst_depay_class_init (GstRtpGSTDepayClass * klass)
{
GObjectClass *gobject_class;
GstElementClass *gstelement_class;
GstRTPBaseDepayloadClass *gstrtpbasedepayload_class;
GST_DEBUG_CATEGORY_INIT (rtpgstdepay_debug, "rtpgstdepay", 0,
"Gstreamer RTP Depayloader");
gobject_class = (GObjectClass *) klass;
gstelement_class = (GstElementClass *) klass;
gstrtpbasedepayload_class = (GstRTPBaseDepayloadClass *) klass;
gobject_class->finalize = gst_rtp_gst_depay_finalize;
gstelement_class->change_state = gst_rtp_gst_depay_change_state;
gst_element_class_add_pad_template (gstelement_class,
gst_static_pad_template_get (&gst_rtp_gst_depay_src_template));
gst_element_class_add_pad_template (gstelement_class,
gst_static_pad_template_get (&gst_rtp_gst_depay_sink_template));
gst_element_class_set_static_metadata (gstelement_class,
"GStreamer depayloader", "Codec/Depayloader/Network",
"Extracts GStreamer buffers from RTP packets",
"Wim Taymans <wim.taymans@gmail.com>");
gstrtpbasedepayload_class->set_caps = gst_rtp_gst_depay_setcaps;
gstrtpbasedepayload_class->process = gst_rtp_gst_depay_process;
}
static void
gst_rtp_gst_depay_init (GstRtpGSTDepay * rtpgstdepay)
{
rtpgstdepay->adapter = gst_adapter_new ();
}
static void
gst_rtp_gst_depay_finalize (GObject * object)
{
GstRtpGSTDepay *rtpgstdepay;
rtpgstdepay = GST_RTP_GST_DEPAY (object);
gst_rtp_gst_depay_reset (rtpgstdepay);
g_object_unref (rtpgstdepay->adapter);
G_OBJECT_CLASS (parent_class)->finalize (object);
}
static void
store_cache (GstRtpGSTDepay * rtpgstdepay, guint CV, GstCaps * caps)
{
if (rtpgstdepay->CV_cache[CV])
gst_caps_unref (rtpgstdepay->CV_cache[CV]);
rtpgstdepay->CV_cache[CV] = caps;
}
static void
gst_rtp_gst_depay_reset (GstRtpGSTDepay * rtpgstdepay)
{
guint i;
gst_adapter_clear (rtpgstdepay->adapter);
rtpgstdepay->current_CV = 0;
for (i = 0; i < 8; i++)
store_cache (rtpgstdepay, i, NULL);
}
static gboolean
gst_rtp_gst_depay_setcaps (GstRTPBaseDepayload * depayload, GstCaps * caps)
{
GstRtpGSTDepay *rtpgstdepay;
GstStructure *structure;
gint clock_rate;
gboolean res;
const gchar *capsenc;
rtpgstdepay = GST_RTP_GST_DEPAY (depayload);
structure = gst_caps_get_structure (caps, 0);
if (!gst_structure_get_int (structure, "clock-rate", &clock_rate))
clock_rate = 90000;
depayload->clock_rate = clock_rate;
capsenc = gst_structure_get_string (structure, "caps");
if (capsenc) {
GstCaps *outcaps;
gsize out_len;
gchar *capsstr;
const gchar *capsver;
guint CV;
/* decode caps */
capsstr = (gchar *) g_base64_decode (capsenc, &out_len);
outcaps = gst_caps_from_string (capsstr);
g_free (capsstr);
/* parse version */
capsver = gst_structure_get_string (structure, "capsversion");
if (capsver) {
CV = atoi (capsver);
} else {
/* no version, assume 0 */
CV = 0;
}
/* store in cache */
rtpgstdepay->current_CV = CV;
gst_caps_ref (outcaps);
store_cache (rtpgstdepay, CV, outcaps);
res = gst_pad_set_caps (depayload->srcpad, outcaps);
gst_caps_unref (outcaps);
} else {
GST_WARNING_OBJECT (depayload, "no caps given");
rtpgstdepay->current_CV = -1;
res = TRUE;
}
return res;
}
static gboolean
read_length (GstRtpGSTDepay * rtpgstdepay, guint8 * data, guint size,
guint * length, guint * skip)
{
guint b, len, offset;
/* start reading the length, we need this to skip to the data later */
len = offset = 0;
do {
if (offset >= size)
return FALSE;
b = data[offset++];
len = (len << 7) | (b & 0x7f);
} while (b & 0x80);
/* check remaining buffer size */
if (size - offset < len)
return FALSE;
*length = len;
*skip = offset;
return TRUE;
}
static GstCaps *
read_caps (GstRtpGSTDepay * rtpgstdepay, GstBuffer * buf, guint * skip)
{
guint offset, length;
GstCaps *caps;
GstMapInfo map;
gst_buffer_map (buf, &map, GST_MAP_READ);
GST_DEBUG_OBJECT (rtpgstdepay, "buffer size %" G_GSIZE_FORMAT, map.size);
if (!read_length (rtpgstdepay, map.data, map.size, &length, &offset))
goto too_small;
GST_DEBUG_OBJECT (rtpgstdepay, "parsing caps %s", &map.data[offset]);
/* parse and store in cache */
caps = gst_caps_from_string ((gchar *) & map.data[offset]);
gst_buffer_unmap (buf, &map);
*skip = length + offset;
return caps;
too_small:
{
GST_ELEMENT_WARNING (rtpgstdepay, STREAM, DECODE,
("Buffer too small."), (NULL));
gst_buffer_unmap (buf, &map);
return NULL;
}
}
static GstEvent *
read_event (GstRtpGSTDepay * rtpgstdepay, guint type,
GstBuffer * buf, guint * skip)
{
guint offset, length;
GstStructure *s;
GstEvent *event;
GstEventType etype;
gchar *end;
GstMapInfo map;
gst_buffer_map (buf, &map, GST_MAP_READ);
GST_DEBUG_OBJECT (rtpgstdepay, "buffer size %" G_GSIZE_FORMAT, map.size);
if (!read_length (rtpgstdepay, map.data, map.size, &length, &offset))
goto too_small;
GST_DEBUG_OBJECT (rtpgstdepay, "parsing event %s", &map.data[offset]);
/* parse */
s = gst_structure_from_string ((gchar *) & map.data[offset], &end);
gst_buffer_unmap (buf, &map);
if (s == NULL)
goto parse_failed;
switch (type) {
case 1:
etype = GST_EVENT_TAG;
break;
case 2:
etype = GST_EVENT_CUSTOM_DOWNSTREAM;
break;
case 3:
etype = GST_EVENT_CUSTOM_BOTH;
break;
case 4:
etype = GST_EVENT_STREAM_START;
break;
default:
goto unknown_event;
}
event = gst_event_new_custom (etype, s);
*skip = length + offset;
return event;
too_small:
{
GST_ELEMENT_WARNING (rtpgstdepay, STREAM, DECODE,
("Buffer too small."), (NULL));
gst_buffer_unmap (buf, &map);
return NULL;
}
parse_failed:
{
GST_WARNING_OBJECT (rtpgstdepay, "could not parse event");
return NULL;
}
unknown_event:
{
GST_DEBUG_OBJECT (rtpgstdepay, "unknown event type");
gst_structure_free (s);
return NULL;
}
}
static GstBuffer *
gst_rtp_gst_depay_process (GstRTPBaseDepayload * depayload, GstBuffer * buf)
{
GstRtpGSTDepay *rtpgstdepay;
GstBuffer *subbuf, *outbuf = NULL;
gint payload_len;
guint8 *payload;
guint CV, frag_offset, avail, offset;
GstRTPBuffer rtp = { NULL };
rtpgstdepay = GST_RTP_GST_DEPAY (depayload);
gst_rtp_buffer_map (buf, GST_MAP_READ, &rtp);
payload_len = gst_rtp_buffer_get_payload_len (&rtp);
if (payload_len <= 8)
goto empty_packet;
if (GST_BUFFER_IS_DISCONT (buf)) {
GST_WARNING_OBJECT (rtpgstdepay, "DISCONT, clear adapter");
gst_adapter_clear (rtpgstdepay->adapter);
}
payload = gst_rtp_buffer_get_payload (&rtp);
/* strip off 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
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* |C| CV |D|0|0|0| ETYPE | MBZ |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Frag_offset |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
frag_offset =
(payload[4] << 24) | (payload[5] << 16) | (payload[6] << 8) | payload[7];
avail = gst_adapter_available (rtpgstdepay->adapter);
if (avail != frag_offset)
goto wrong_frag;
/* subbuffer skipping the 8 header bytes */
subbuf = gst_rtp_buffer_get_payload_subbuffer (&rtp, 8, -1);
gst_adapter_push (rtpgstdepay->adapter, subbuf);
offset = 0;
if (gst_rtp_buffer_get_marker (&rtp)) {
guint avail;
GstCaps *outcaps;
/* take the buffer */
avail = gst_adapter_available (rtpgstdepay->adapter);
outbuf = gst_adapter_take_buffer (rtpgstdepay->adapter, avail);
CV = (payload[0] >> 4) & 0x7;
if (payload[0] & 0x80) {
guint size;
/* C bit, we have inline caps */
outcaps = read_caps (rtpgstdepay, outbuf, &size);
if (outcaps == NULL)
goto no_caps;
GST_DEBUG_OBJECT (rtpgstdepay,
"inline caps %u, length %u, %" GST_PTR_FORMAT, CV, size, outcaps);
store_cache (rtpgstdepay, CV, outcaps);
/* skip caps */
offset += size;
avail -= size;
}
if (payload[1]) {
guint size;
GstEvent *event;
/* we have an event */
event = read_event (rtpgstdepay, payload[1], outbuf, &size);
if (event == NULL)
goto no_event;
GST_DEBUG_OBJECT (rtpgstdepay,
"inline event, length %u, %" GST_PTR_FORMAT, size, event);
gst_pad_push_event (depayload->srcpad, event);
/* no buffer after event */
avail = 0;
}
if (avail) {
if (offset != 0) {
GstBuffer *temp;
GST_DEBUG_OBJECT (rtpgstdepay, "sub buffer: offset %u, size %u", offset,
avail);
temp =
gst_buffer_copy_region (outbuf, GST_BUFFER_COPY_ALL, offset, avail);
gst_buffer_unref (outbuf);
outbuf = temp;
}
/* see what caps we need */
if (CV != rtpgstdepay->current_CV) {
/* we need to switch caps, check if we have the caps */
if ((outcaps = rtpgstdepay->CV_cache[CV]) == NULL)
goto missing_caps;
GST_DEBUG_OBJECT (rtpgstdepay,
"need caps switch from %u to %u, %" GST_PTR_FORMAT,
rtpgstdepay->current_CV, CV, outcaps);
/* and set caps */
if (gst_pad_set_caps (depayload->srcpad, outcaps))
rtpgstdepay->current_CV = CV;
}
if (payload[0] & 0x8)
GST_BUFFER_FLAG_SET (outbuf, GST_BUFFER_FLAG_DELTA_UNIT);
} else {
gst_buffer_unref (outbuf);
outbuf = NULL;
}
}
gst_rtp_buffer_unmap (&rtp);
return outbuf;
/* ERRORS */
empty_packet:
{
GST_ELEMENT_WARNING (rtpgstdepay, STREAM, DECODE,
("Empty Payload."), (NULL));
gst_rtp_buffer_unmap (&rtp);
return NULL;
}
wrong_frag:
{
gst_adapter_clear (rtpgstdepay->adapter);
gst_rtp_buffer_unmap (&rtp);
GST_LOG_OBJECT (rtpgstdepay, "wrong fragment, skipping");
return NULL;
}
no_caps:
{
GST_WARNING_OBJECT (rtpgstdepay, "failed to parse caps");
gst_buffer_unref (outbuf);
gst_rtp_buffer_unmap (&rtp);
return NULL;
}
no_event:
{
GST_WARNING_OBJECT (rtpgstdepay, "failed to parse event");
gst_buffer_unref (outbuf);
gst_rtp_buffer_unmap (&rtp);
return NULL;
}
missing_caps:
{
GST_ELEMENT_WARNING (rtpgstdepay, STREAM, DECODE,
("Missing caps %u.", CV), (NULL));
gst_buffer_unref (outbuf);
gst_rtp_buffer_unmap (&rtp);
return NULL;
}
}
static GstStateChangeReturn
gst_rtp_gst_depay_change_state (GstElement * element, GstStateChange transition)
{
GstRtpGSTDepay *rtpgstdepay;
GstStateChangeReturn ret;
rtpgstdepay = GST_RTP_GST_DEPAY (element);
switch (transition) {
case GST_STATE_CHANGE_READY_TO_PAUSED:
gst_rtp_gst_depay_reset (rtpgstdepay);
break;
default:
break;
}
ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
switch (transition) {
case GST_STATE_CHANGE_PAUSED_TO_READY:
gst_rtp_gst_depay_reset (rtpgstdepay);
break;
default:
break;
}
return ret;
}
gboolean
gst_rtp_gst_depay_plugin_init (GstPlugin * plugin)
{
return gst_element_register (plugin, "rtpgstdepay",
GST_RANK_MARGINAL, GST_TYPE_RTP_GST_DEPAY);
}