Struct libpulse_binding::def::TimingInfo
source ·
[−]#[repr(C)]pub struct TimingInfo {Show 13 fields
pub timestamp: UnixTs,
pub synchronized_clocks: i32,
pub sink_usec: MicroSeconds,
pub source_usec: MicroSeconds,
pub transport_usec: MicroSeconds,
pub playing: i32,
pub write_index_corrupt: i32,
pub write_index: i64,
pub read_index_corrupt: i32,
pub read_index: i64,
pub configured_sink_usec: MicroSeconds,
pub configured_source_usec: MicroSeconds,
pub since_underrun: i64,
}
Expand description
A structure for all kinds of timing information of a stream.
See Stream::update_timing_info()
and Stream::get_timing_info()
.
The total output latency a sample that is written with Stream::write()
takes to be played
may be estimated by:
sink_usec + buffer_usec + transport_usec
(Where buffer_usec
is defined as the result of passing write_index - read_index
to
Spec::bytes_to_usec()
). The output buffer which buffer_usec
relates to may be manipulated
freely (with Stream::write()
’s seek
argument, Stream::flush()
and friends), the
buffers sink_usec
and source_usec
relate to are first-in first-out (FIFO) buffers which
cannot be flushed or manipulated in any way. The total input latency a sample that is recorded
takes to be delivered to the application is:
source_usec + buffer_usec + transport_usec - sink_usec
(Take care of sign issues!). When connected to a monitor source sink_usec
contains the latency
of the owning sink. The two latency estimations described here are implemented in
Stream::get_latency()
.
All time values are in the sound card clock domain, unless noted otherwise. The sound card clock usually runs at a slightly different rate than the system clock.
Please note that this structure can be extended as part of evolutionary API updates at any time in any new release.
Fields
timestamp: UnixTs
The system clock time when this timing info structure was current.
synchronized_clocks: i32
Non-zero if the local and the remote machine have synchronized clocks. If synchronized
clocks are detected transport_usec
becomes much more reliable. However, the code that
detects synchronized clocks is very limited and unreliable itself.
sink_usec: MicroSeconds
Time in usecs a sample takes to be played on the sink. For playback streams and record streams connected to a monitor source.
source_usec: MicroSeconds
Time in usecs a sample takes from being recorded to being delivered to the application. Only for record streams.
transport_usec: MicroSeconds
Estimated time in usecs a sample takes to be transferred to/from the daemon. For both playback and record streams.
playing: i32
Non-zero when the stream is currently not underrun and data is being passed on to the
device. Only for playback streams. This field does not say whether the data is actually
already being played. To determine this check whether since_underrun
(converted to usec)
is larger than sink_usec
.
write_index_corrupt: i32
Non-zero if write_index
is not up-to-date because a local write command that corrupted it
has been issued in the time since this latency info was current. Only write commands with
SeekMode::RelativeOnRead
and SeekMode::RelativeEnd
can corrupt write_index
.
write_index: i64
Current write index into the playback buffer in bytes.
Think twice before using this for seeking purposes: it might be out of date at the time you
want to use it. Consider using SeekMode::Relative
instead.
read_index_corrupt: i32
Non-zero if read_index
is not up-to-date because a local pause or flush request that
corrupted it has been issued in the time since this latency info was current.
read_index: i64
Current read index into the playback buffer in bytes.
Think twice before using this for seeking purposes: it might be out of date at the time you
want to use it. Consider using SeekMode::RelativeOnRead
instead.
configured_sink_usec: MicroSeconds
The configured latency for the sink.
configured_source_usec: MicroSeconds
The configured latency for the source.
since_underrun: i64
Bytes that were handed to the sink since the last underrun happened, or since playback
started again after the last underrun. playing
will tell you which case it is.
Trait Implementations
Performs the conversion.
This method tests for self
and other
values to be equal, and is used
by ==
. Read more
This method tests for !=
.
Auto Trait Implementations
impl RefUnwindSafe for TimingInfo
impl Send for TimingInfo
impl Sync for TimingInfo
impl Unpin for TimingInfo
impl UnwindSafe for TimingInfo
Blanket Implementations
Mutably borrows from an owned value. Read more