level

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

Synopsis

struct              GstLevel;

Object Hierarchy

  GObject
   +----GInitiallyUnowned
         +----GstObject
               +----GstElement
                     +----GstBaseTransform
                           +----GstLevel

Properties

  "interval"                 guint64               : Read / Write
  "message"                  gboolean              : Read / Write
  "peak-falloff"             gdouble               : Read / Write
  "peak-ttl"                 guint64               : Read / Write

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

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