The size of the packets sent between network clocks.
#GstNetAddressMeta can be used to store a network address (a #GSocketAddress)
in a #GstBuffer so that it network elements can track the to and from address
of the buffer.
the parent type
a #GSocketAddress stored as metadata
#GstNetClientClock implements a custom #GstClock that synchronizes its time
to a remote time provider such as #GstNetTimeProvider. #GstNtpClock
implements a #GstClock that synchronizes its time to a remote NTPv4 server.
A new clock is created with gst_net_client_clock_new() or
gst_ntp_clock_new(), which takes the address and port of the remote time
provider along with a name and an initial time.
This clock will poll the time provider and will update its calibration
parameters based on the local and remote observations.
The "round-trip" property limits the maximum round trip packets can take.
Various parameters of the clock can be configured with the parent #GstClock
"timeout", "window-size" and "window-threshold" object properties.
A #GstNetClientClock and #GstNtpClock is typically set on a #GstPipeline with
gst_pipeline_use_clock().
If you set a #GstBus on the clock via the "bus" object property, it will
send @GST_MESSAGE_ELEMENT messages with an attached #GstStructure containing
statistics about clock accuracy and network traffic.
Create a new #GstNetClientInternalClock that will report the time
provided by the #GstNetTimeProvider on @remote_address and
@remote_port.
a new #GstClock that receives a time from the remote
clock.
a name for the clock
the address or hostname of the remote clock provider
the port of the remote clock provider
initial time of the clock
#GstNetControlMessageMeta can be used to store control messages (ancillary
data) which was received with or is to be sent alongside the buffer data.
When used with socket sinks and sources which understand this meta it allows
sending and receiving ancillary data such as unix credentials (See
#GUnixCredentialsMessage) and Unix file descriptions (See #GUnixFDMessage).
the parent type
a #GSocketControlMessage stored as metadata
Various functions for receiving, sending an serializing #GstNetTimePacket
structures.
the local time when this packet was sent
the remote time observation
Creates a new #GstNetTimePacket from a buffer received over the network. The
caller is responsible for ensuring that @buffer is at least
#GST_NET_TIME_PACKET_SIZE bytes long.
If @buffer is #NULL, the local and remote times will be set to
#GST_CLOCK_TIME_NONE.
MT safe. Caller owns return value (gst_net_time_packet_free to free).
The new #GstNetTimePacket.
a buffer from which to construct the packet, or NULL
Make a copy of @packet.
a copy of @packet, free with gst_net_time_packet_free().
the #GstNetTimePacket
Free @packet.
the #GstNetTimePacket
Sends a #GstNetTimePacket over a socket.
MT safe.
TRUE if successful, FALSE in case an error occurred.
the #GstNetTimePacket to send
socket to send the time packet on
address to send the time packet to
Serialized a #GstNetTimePacket into a newly-allocated sequence of
#GST_NET_TIME_PACKET_SIZE bytes, in network byte order. The value returned is
suitable for passing to write(2) or sendto(2) for communication over the
network.
MT safe. Caller owns return value (g_free to free).
A newly allocated sequence of #GST_NET_TIME_PACKET_SIZE bytes.
the #GstNetTimePacket
Receives a #GstNetTimePacket over a socket. Handles interrupted system
calls, but otherwise returns NULL on error.
a new #GstNetTimePacket, or NULL on error. Free
with gst_net_time_packet_free() when done.
socket to receive the time packet on
address of variable to return sender address
This object exposes the time of a #GstClock on the network.
A #GstNetTimeProvider is created with gst_net_time_provider_new() which
takes a #GstClock, an address and a port number as arguments.
After creating the object, a client clock such as #GstNetClientClock can
query the exposed clock over the network for its values.
The #GstNetTimeProvider typically wraps the clock used by a #GstPipeline.
Allows network clients to get the current time of @clock.
the new #GstNetTimeProvider, or NULL on error
a #GstClock to export over the network
an address to bind on as a dotted quad
(xxx.xxx.xxx.xxx), IPv6 address, or NULL to bind to all addresses
a port to bind on, or 0 to let the kernel choose
Create a new #GstNtpClock that will report the time provided by
the NTPv4 server on @remote_address and @remote_port.
a new #GstClock that receives a time from the remote
clock.
a name for the clock
the address or hostname of the remote clock provider
the port of the remote clock provider
initial time of the clock
PTP clock identification that can be passed to gst_ptp_init() to
automatically select one based on the MAC address of interfaces
GstPtpClock implements a PTP (IEEE1588:2008) ordinary clock in slave-only
mode, that allows a GStreamer pipeline to synchronize to a PTP network
clock in some specific domain.
The PTP subsystem can be initialized with gst_ptp_init(), which then starts
a helper process to do the actual communication via the PTP ports. This is
required as PTP listens on ports < 1024 and thus requires special
privileges. Once this helper process is started, the main process will
synchronize to all PTP domains that are detected on the selected
interfaces.
gst_ptp_clock_new() then allows to create a GstClock that provides the PTP
time from a master clock inside a specific PTP domain. This clock will only
return valid timestamps once the timestamps in the PTP domain are known. To
check this, you can use gst_clock_wait_for_sync(), the GstClock::synced
signal and gst_clock_is_synced().
To gather statistics about the PTP clock synchronization,
gst_ptp_statistics_callback_add() can be used. This gives the application
the possibility to collect all kinds of statistics from the clock
synchronization.
Creates a new PTP clock instance that exports the PTP time of the master
clock in @domain. This clock can be slaved to other clocks as needed.
If gst_ptp_init() was not called before, this will call gst_ptp_init() with
default parameters.
This clock only returns valid timestamps after it received the first
times from the PTP master clock on the network. Once this happens the
GstPtpClock::internal-clock property will become non-NULL. You can
check this with gst_clock_wait_for_sync(), the GstClock::synced signal and
gst_clock_is_synced().
Name of the clock
PTP domain
Opaque #GstPtpClockClass structure.
parented to #GstSystemClockClass
The statistics can be the following structures:
GST_PTP_STATISTICS_NEW_DOMAIN_FOUND:
"domain" G_TYPE_UINT The domain identifier of the domain
"clock" GST_TYPE_CLOCK The internal clock that is slaved to the
PTP domain
GST_PTP_STATISTICS_BEST_MASTER_CLOCK_SELECTED:
"domain" G_TYPE_UINT The domain identifier of the domain
"master-clock-id" G_TYPE_UINT64 PTP clock identifier of the selected master
clock
"master-clock-port" G_TYPE_UINT PTP port number of the selected master clock
"grandmaster-clock-id" G_TYPE_UINT64 PTP clock identifier of the grandmaster clock
GST_PTP_STATISTICS_PATH_DELAY_MEASURED:
"domain" G_TYPE_UINT The domain identifier of the domain
"mean-path-delay-avg" GST_TYPE_CLOCK_TIME Average mean path delay
"mean-path-delay" GST_TYPE_CLOCK_TIME Latest mean path delay
"delay-request-delay" GST_TYPE_CLOCK_TIME Delay of DELAY_REQ / DELAY_RESP messages
GST_PTP_STATISTICS_TIME_UPDATED:
"domain" G_TYPE_UINT The domain identifier of the domain
"mean-path-delay-avg" GST_TYPE_CLOCK_TIME Average mean path delay
"local-time" GST_TYPE_CLOCK_TIME Local time that corresponds to ptp-time
"ptp-time" GST_TYPE_CLOCK_TIME Newly measured PTP time at local-time
"estimated-ptp-time" GST_TYPE_CLOCK_TIME Estimated PTP time based on previous measurements
"discontinuity" G_TYPE_INT64 Difference between estimated and measured PTP time
"synced" G_TYPE_BOOLEAN Currently synced to the remote clock
"r-squared" G_TYPE_DOUBLE R² of clock estimation regression
"internal-time" GST_TYPE_CLOCK_TIME Internal time clock parameter
"external-time" GST_TYPE_CLOCK_TIME External time clock parameter
"rate-num" G_TYPE_UINT64 Internal/external rate numerator
"rate-den" G_TYPE_UINT64 Internal/external rate denominator
"rate" G_TYPE_DOUBLE Internal/external rate
If %FALSE is returned, the callback is removed and never called again.
PTP domain identifier
New statistics
Data passed to gst_ptp_statistics_callback_add()
Attaches @addr as metadata in a #GstNetAddressMeta to @buffer.
a #GstNetAddressMeta connected to @buffer
a #GstBuffer
a @GSocketAddress to connect to @buffer
Attaches @message as metadata in a #GstNetControlMessageMeta to @buffer.
a #GstNetControlMessageMeta connected to @buffer
a #GstBuffer
a @GSocketControlMessage to attach to @buffer
Find the #GstNetAddressMeta on @buffer.
the #GstNetAddressMeta or %NULL when there
is no such metadata on @buffer.
a #GstBuffer
Receives a #GstNetTimePacket over a socket. Handles interrupted system
calls, but otherwise returns NULL on error.
a new #GstNetTimePacket, or NULL on error. Free
with gst_net_time_packet_free() when done.
socket to receive the time packet on
address of variable to return sender address
Deinitialize the GStreamer PTP subsystem and stop the PTP clock. If there
are any remaining GstPtpClock instances, they won't be further synchronized
to the PTP network clock.
Initialize the GStreamer PTP subsystem and create a PTP ordinary clock in
slave-only mode for all domains on the given @interfaces with the
given @clock_id.
If @clock_id is %GST_PTP_CLOCK_ID_NONE, a clock id is automatically
generated from the MAC address of the first network interface.
This function is automatically called by gst_ptp_clock_new() with default
parameters if it wasn't called before.
%TRUE if the GStreamer PTP clock subsystem could be initialized.
PTP clock id of this process' clock or %GST_PTP_CLOCK_ID_NONE
network interfaces to run the clock on
Check if the GStreamer PTP clock subsystem is initialized.
%TRUE if the GStreamer PTP clock subsystem is intialized.
Check if PTP clocks are generally supported on this system, and if previous
initializations did not fail.
%TRUE if PTP clocks are generally supported on this system, and
previous initializations did not fail.
Installs a new statistics callback for gathering PTP statistics. See
GstPtpStatisticsCallback for a list of statistics that are provided.
Id for the callback that can be passed to
gst_ptp_statistics_callback_remove()
GstPtpStatisticsCallback to call
Data to pass to the callback
GDestroyNotify to destroy the data
Removes a PTP statistics callback that was previously added with
gst_ptp_statistics_callback_add().
Callback id to remove