gstreamer/subprojects/gst-plugins-good/gst/rtpmanager/gstrtphdrext-streamid.c
Matthew Waters 1e55e2d654 rtpmanager: add support for RFC8852 (rid) RTP header extensions
Both for regular RID and for adding on a repaired (RTX) etc stream.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/1759>
2022-03-21 03:18:18 +00:00

297 lines
8.7 KiB
C

/* GStreamer
* Copyright (C) <2021> Matthew Waters <matthew@centricular.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., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/**
* SECTION:element-rtphdrextstreamid
* @title: rtphdrextstreamid
* @short_description: RTP SDES Header Extension for RFC8852 RtpStreamId
* Extension
* @see_also: #GstRTPHeaderExtension, #GstRTPBasePayload, #GstRTPBaseDepayload, gstrtpbuffer
*
* Since: 1.22
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <gst/rtp/gstrtpbuffer.h>
#include "gstrtphdrext-streamid.h"
GST_DEBUG_CATEGORY_STATIC (rtphdrext_stream_id_debug);
#define GST_CAT_DEFAULT (rtphdrext_stream_id_debug)
#define RID_EXTMAP_STR GST_RTP_HDREXT_BASE "sdes:rtp-stream-id"
enum
{
PROP_0,
PROP_RID,
};
struct _GstRTPHeaderExtensionStreamId
{
GstRTPHeaderExtension parent;
char *rid;
};
#define gst_rtp_header_extension_stream_id_parent_class parent_class
G_DEFINE_TYPE_WITH_CODE (GstRTPHeaderExtensionStreamId,
gst_rtp_header_extension_stream_id, GST_TYPE_RTP_HEADER_EXTENSION,
GST_DEBUG_CATEGORY_INIT (GST_CAT_DEFAULT, "rtphdrextstreamid", 0,
"RTP RFC8852 RtpStreamId Header Extensions");
);
GST_ELEMENT_REGISTER_DEFINE (rtphdrextstreamid,
"rtphdrextstreamid", GST_RANK_MARGINAL,
GST_TYPE_RTP_HEADER_EXTENSION_STREAM_ID);
static GstRTPHeaderExtensionFlags
gst_rtp_header_extension_stream_id_get_supported_flags
(GstRTPHeaderExtension * ext)
{
GstRTPHeaderExtensionStreamId *self =
GST_RTP_HEADER_EXTENSION_STREAM_ID (ext);
GstRTPHeaderExtensionFlags flags =
GST_RTP_HEADER_EXTENSION_ONE_BYTE | GST_RTP_HEADER_EXTENSION_TWO_BYTE;
gssize rid_len = -1;
GST_OBJECT_LOCK (ext);
if (self->rid)
rid_len = strlen (self->rid);
GST_OBJECT_UNLOCK (ext);
if (rid_len > 16)
flags = GST_RTP_HEADER_EXTENSION_TWO_BYTE;
return flags;
}
static gsize
gst_rtp_header_extension_stream_id_get_max_size (GstRTPHeaderExtension *
ext, const GstBuffer * buffer)
{
if (gst_rtp_header_extension_stream_id_get_supported_flags (ext) &
GST_RTP_HEADER_EXTENSION_ONE_BYTE)
return 16;
else
return 255;
}
static gssize
gst_rtp_header_extension_stream_id_write (GstRTPHeaderExtension * ext,
const GstBuffer * input_meta, GstRTPHeaderExtensionFlags write_flags,
GstBuffer * output, guint8 * data, gsize size)
{
GstRTPHeaderExtensionStreamId *self =
GST_RTP_HEADER_EXTENSION_STREAM_ID (ext);
gsize len = 0;
g_return_val_if_fail (size >=
gst_rtp_header_extension_stream_id_get_max_size (ext, NULL), -1);
g_return_val_if_fail (write_flags &
gst_rtp_header_extension_stream_id_get_supported_flags (ext), -1);
GST_OBJECT_LOCK (ext);
if (!self->rid) {
GST_LOG_OBJECT (self, "no rid to write");
goto out;
}
/* TODO: we don't need to always add rid, we can selectively omit it from e.g.
* non-video-keyframes or some percentage of the produced frames, e.g. RFC8852
* mentions possibly using packet-loss as a indication of how often to add mid
* to packets */
len = strlen (self->rid);
if ((write_flags & GST_RTP_HEADER_EXTENSION_TWO_BYTE) == 0 && len > 16) {
GST_DEBUG_OBJECT (self, "cannot write a rid of size %" G_GSIZE_FORMAT
" without using the two byte extension format", len);
len = 0;
goto out;
}
if (len > 0) {
GST_LOG_OBJECT (self, "writing rid \'%s\'", self->rid);
memcpy (data, self->rid, len);
}
out:
GST_OBJECT_UNLOCK (ext);
return len;
}
static gboolean
gst_rtp_header_extension_stream_id_read (GstRTPHeaderExtension * ext,
GstRTPHeaderExtensionFlags read_flags, const guint8 * data, gsize size,
GstBuffer * buffer)
{
GstRTPHeaderExtensionStreamId *self =
GST_RTP_HEADER_EXTENSION_STREAM_ID (ext);
gboolean notify = FALSE;
if (!data || size == 0)
return TRUE;
if (read_flags & GST_RTP_HEADER_EXTENSION_ONE_BYTE && (size < 1 || size > 16)) {
GST_ERROR_OBJECT (ext,
"one-byte header extensions must be between 1 and 16 bytes inculusive");
return FALSE;
}
GST_OBJECT_LOCK (self);
if (!self->rid || strncmp ((const char *) data, self->rid, size) != 0) {
g_clear_pointer (&self->rid, g_free);
self->rid = g_strndup ((const char *) data, size);
notify = TRUE;
}
GST_OBJECT_UNLOCK (self);
if (notify)
g_object_notify ((GObject *) self, "rid");
return TRUE;
}
static void
gst_rtp_header_extension_stream_id_get_property (GObject * object,
guint prop_id, GValue * value, GParamSpec * pspec)
{
GstRTPHeaderExtensionStreamId *self =
GST_RTP_HEADER_EXTENSION_STREAM_ID (object);
switch (prop_id) {
case PROP_RID:
GST_OBJECT_LOCK (self);
g_value_set_string (value, self->rid);
GST_OBJECT_UNLOCK (self);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static gboolean
validate_rid (const char *rid)
{
const char *iter;
/* For avoidance of doubt, the only allowed byte values for
* these IDs are decimal 48 through 57, 65 through 90, and 97 through
* 122.
*/
for (iter = rid; iter && iter[0]; iter++) {
if (iter[0] < 48)
return FALSE;
if (iter[0] > 122)
return FALSE;
if (iter[0] > 57 && iter[0] < 65)
return FALSE;
if (iter[0] > 90 && iter[0] < 97)
return FALSE;
}
return TRUE;
}
static void
gst_rtp_header_extension_stream_id_set_property (GObject * object,
guint prop_id, const GValue * value, GParamSpec * pspec)
{
GstRTPHeaderExtensionStreamId *self =
GST_RTP_HEADER_EXTENSION_STREAM_ID (object);
switch (prop_id) {
case PROP_RID:{
const char *rid;
GST_OBJECT_LOCK (self);
rid = g_value_get_string (value);
if (!validate_rid (rid)) {
GST_WARNING_OBJECT (self, "Could not set rid \'%s\'. Validation failed",
rid);
} else {
g_clear_pointer (&self->rid, g_free);
self->rid = g_strdup (rid);
}
GST_OBJECT_UNLOCK (self);
break;
}
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_rtp_header_extension_stream_id_finalize (GObject * object)
{
GstRTPHeaderExtensionStreamId *self =
GST_RTP_HEADER_EXTENSION_STREAM_ID (object);
g_clear_pointer (&self->rid, g_free);
G_OBJECT_CLASS (parent_class)->finalize (object);
}
static void
gst_rtp_header_extension_stream_id_class_init
(GstRTPHeaderExtensionStreamIdClass * klass)
{
GstRTPHeaderExtensionClass *rtp_hdr_class;
GstElementClass *gstelement_class;
GObjectClass *gobject_class;
rtp_hdr_class = (GstRTPHeaderExtensionClass *) klass;
gobject_class = (GObjectClass *) klass;
gstelement_class = (GstElementClass *) klass;
gobject_class->set_property = gst_rtp_header_extension_stream_id_set_property;
gobject_class->get_property = gst_rtp_header_extension_stream_id_get_property;
gobject_class->finalize = gst_rtp_header_extension_stream_id_finalize;
/**
* rtphdrextstreamid:rid:
*
* The RtpStreamID (RID) value either last retrieved from the RTP
* Header extension, or to set on outgoing RTP packets.
*
* Since: 1.22
*/
g_object_class_install_property (gobject_class, PROP_RID,
g_param_spec_string ("rid", "rid",
"The RtpStreamId (RID) value last read or to write from/to "
"RTP buffers", NULL, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
rtp_hdr_class->get_supported_flags =
gst_rtp_header_extension_stream_id_get_supported_flags;
rtp_hdr_class->get_max_size = gst_rtp_header_extension_stream_id_get_max_size;
rtp_hdr_class->write = gst_rtp_header_extension_stream_id_write;
rtp_hdr_class->read = gst_rtp_header_extension_stream_id_read;
gst_element_class_set_static_metadata (gstelement_class,
"RTP Header Extension RFC8852 Stream ID", GST_RTP_HDREXT_ELEMENT_CLASS,
"Extends RTP packets to add or retrieve a RtpStreamId (RID) "
"value as specified in RFC8852",
"Matthew Waters <matthew@centricular.com>");
gst_rtp_header_extension_class_set_uri (rtp_hdr_class, RID_EXTMAP_STR);
}
static void
gst_rtp_header_extension_stream_id_init
(GstRTPHeaderExtensionStreamId * self)
{
}