Recherche Google
IntroductionSignal Manipulation > Noise Removal > Processing Noise Removal
page précédentepage suivante

Processing Noise Removal

Once a noise zone is defined, the data of the analysis can be applied in the noise removal processing. The spectral component whose amplitude is inferior to a given threshold will be removed.

Dialogue Window

Access

Select Processing/Noise Removal. The following dialogue window will open.

This window is devided into three zones, whose parameters determine the quality of the noise removal, and its application range :

  • noise removal mode, rate and components to be processed – upper part of the window

  • FFT settings – central part of the window :

  • selection of an area or channel, export format – lower part of the window

Required Noise Zone

If no noise zone has been defined, you will get an error message.

Parameters

FFT Settings

These parameters are thoroughly detailed in the corresponding section of this documentation.

FFT Principles

The FFT parameters applied for the definition of the noise zones in the realtime processing settings are automatically upgraded during the noise removal.

Levels

  • Amplitude Substraction : the noise level to be removed is higher, as the noise print is estimated in terms of amplitude.

  • Energy Substraction : the noise level to be removed is lower, as the noise print is estimated in terms of energy

  • Noise Reduction : reduction level in dB

  • Normalization : the resulting file will be normalized so that the maximum amplitude value doesn't exceed the full scale output of the sound format. Normalization is not valid with the preview.

Preview
Sinusoids Suppression

  • Suppress Sinusoidal Noise : allows to remove sinusoids that could be possibly detected during the analysis.

  • Suppression Attack Time : allows a progressive noise removal. For instance, this means that the possible reverberation on note endings will be preserved.

Managing Amplitude Variations

The level of some components may vary from the detected level in the noise zone.

  • The Overcompensation factor allows to define a variation rate in the signal's components amplitude.

  • With a positive factor, the noise removal threshold is raised, so that peaks above the threshold can be removed.

  • With a negative factor, this threshold is lowered, so that peaks below the threshold can be preserved.

The reduction level is never superior to the specified reduction level.

Restict to Selection

The noise removal can be applied to a selected region of the file, even if the noise zone(s) are located outside this region.

  1. Select the Restrict to Selection option.

    • If you already selected a time region to process, the begin and end time will be displayed in the corresponding prompt

    • You can also enter values in the prompts.

Other Parameters

For detailed information about other common options of the dialogue window, such as export format, and channels processing, see the corresponding page of the Signal Processing section.

Export Format and Channels
page précédentepage suivante
A propos...IRCAMRéalisé avec Scenari