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Owning Palette: Sound Quality VIs

Installed With: Sound and Vibration Measurement Suite

Computes roughness of the sound pressure signal according to Aures' method. Roughness is a hearing sensation related to loudness modulations at frequencies too high to separately discern, such as modulation frequencies greater than 30 Hz.

This VI measures the energy in 24 barks, computes and filters the envelope of the signal in each band, measures the amplitude modulation of each envelope, and then weights the level in each band by the modulation index and a frequency-dependent weighting function. The VI returns the result as the roughness spectrum versus critical band rate, and then integrates the roughness spectrum to measure the roughness.

You can use this VI to analyze short or long signals. However, National Instruments recommends including several cycles of the desired modulation in the analysis. Therefore, a sound pressure signal length of approximately 100 ms is a practical minimum, while 200 to 250 ms is more common.

	diffuse field specifies if the sound field is diffuse (TRUE) or a free field (FALSE). The default is free field (FALSE).
	sound pressure signal [Pa] specifies the sound pressure signal in Pascals. t0 is the start time of the waveform. dt is the time interval in seconds between data points in the waveform. Y contains the data values of the waveform.
	error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use exception control to treat what is normally an error as no error or to treat a warning as an error. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node. status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE. code is the error or warning code. The default is 0. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source specifies the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
	roughness spectrum returns the specific roughness at the critical band rate. The critical band rate is in units of bark.
	roughness [asper] returns the roughness measurement in units of asper.
	roughness info returns information about the roughness measurement. x-axis units returns the units of the x-axis. The valid values are Frequency, Critical Band, and Critical Band Rate. x-axis unit label returns the label of the x-axis. y-axis units returns the units of the y-axis. The valid values are Band Power, Level, Loudness, Sharpness, Roughness, Fluctuation Strength, and Tonality. y-axis unit label returns the label of the y-axis. data attributes returns information about the sound quality measurements this VI analyzes.
	error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error. status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred. code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.