level

level — RMS/Peak/Decaying Peak Level messager for audio/raw

Properties

guint64 interval Read / Write
gboolean message Read / Write
gdouble peak-falloff Read / Write
guint64 peak-ttl Read / Write
gboolean post-messages Read / Write

Types and Values

struct GstLevel

Object Hierarchy

    GObject
    ╰── GInitiallyUnowned
        ╰── GstObject
            ╰── GstElement
                ╰── GstBaseTransform
                    ╰── GstLevel

Description

Level analyses incoming audio buffers and, if the “message” property is TRUE, generates an element message named

"level":

after each interval of time given by the “interval” property. The message's structure contains these fields:

  • GstClockTime "timestamp": the timestamp of the buffer that triggered the message.

  • GstClockTime "stream-time": the stream time of the buffer.

  • GstClockTime "running-time": the running_time of the buffer.

  • GstClockTime "duration": the duration of the buffer.

  • GstClockTime "endtime": the end time of the buffer that triggered the message as stream time (this is deprecated, as it can be calculated from stream-time + duration)

  • GValueArray of gdouble "peak": the peak power level in dB for each channel

  • GValueArray of gdouble "decay": the decaying peak power level in dB for each channel the decaying peak level follows the peak level, but starts dropping if no new peak is reached after the time given by the the time to live. When the decaying peak level drops, it does so at the decay rate as specified by the the peak falloff rate.

  • GValueArray of gdouble "rms": the Root Mean Square (or average power) level in dB for each channel

Example application

<xi:include xmlns:xi="http://www.w3.org/2003/XInclude" parse="text" href="../../../../tests/examples/level/level-example.c" />

Synopsis

Element Information

plugin

level

author

Thomas Vander Stichele <thomas at apestaart dot org>

class

Filter/Analyzer/Audio

Element Pads

name

sink

direction

sink

presence

always

details

audio/x-raw, format=(string){ S8, S16LE, S32LE, F32LE, F64LE }, layout=(string)interleaved, rate=(int)[ 1, 2147483647 ], channels=(int)[ 1, 2147483647 ]

name

src

direction

source

presence

always

details

audio/x-raw, format=(string){ S8, S16LE, S32LE, F32LE, F64LE }, layout=(string)interleaved, rate=(int)[ 1, 2147483647 ], channels=(int)[ 1, 2147483647 ]

Functions

Types and Values

struct GstLevel

struct GstLevel;

Opaque data structure.

Property Details

The “interval” property

  “interval”                 guint64

Interval of time between message posts (in nanoseconds).

Flags: Read / Write

Allowed values: >= 1

Default value: 100000000


The “message” property

  “message”                  gboolean

Post a 'level' message for each passed interval (deprecated).

Flags: Read / Write

Default value: TRUE


The “peak-falloff” property

  “peak-falloff”             gdouble

Decay rate of decay peak after TTL (in dB/sec).

Flags: Read / Write

Allowed values: >= 0

Default value: 10


The “peak-ttl” property

  “peak-ttl”                 guint64

Time To Live of decay peak before it falls back (in nanoseconds).

Flags: Read / Write

Default value: 300000000


The “post-messages” property

  “post-messages”            gboolean

Post messages on the bus with level information.

GstLevel:post-messages is deprecated and should not be used in newly-written code.

use the “post-messages” property

Flags: Read / Write

Default value: TRUE

Since 1.1.0