R: cssSpectrum

cssSpectrum {wrassp} | R Documentation

## cssSpectrum

### Description

calculate cepstrally smoothed spectrum using libassp

### Usage

    cssSpectrum(listOfFiles = NULL, optLogFilePath = NULL, beginTime = 0,
      centerTime = FALSE, endTime = 0, resolution = 40, fftLength = 0,
      windowShift = 5, window = "BLACKMAN", numCeps = 0, toFile = TRUE,
      explicitExt = NULL, outputDirectory = NULL,
      forceToLog = useWrasspLogger, verbose = TRUE)

### Arguments

`listOfFiles` | vector of file paths to be processed by function
`optLogFilePath` | path to option log file
`beginTime` | = <time>: set begin of analysis interval to <time> seconds (default: begin of data)
`centerTime` | = <time>: set single-frame analysis with the analysis window centred at <time> seconds; overrules beginTime, endTime and windowShift options
`endTime` | = <time>: set end of analysis interval to <time> seconds (default: end of data)
`resolution` | = <freq>: set FFT length to the smallest value which results in a freqequency resolution of <freq> Hz or better (default: 40.0)
`fftLength` | = <num>: set FFT length to <num> points (overrules default and 'resolution' option)
`windowShift` | = <dur>: set analysis window shift to <dur> ms (default: 5.0)
`window` | = <type>: set analysis window function to <type> (default: BLACKMAN)
`numCeps` | = <num>: set number of cepstral coeffcients used to <num> (default: sampling rate in kHz + 1; minimum: 2)
`toFile` | write results to file (default extension depends on )
`explicitExt` | set if you wish to overwride the default extension
`outputDirectory` | directory in which output files are stored. Defaults to NULL, i.e. the directory of the input files
`forceToLog` | is set by the global package variable useWrasspLogger. This is set to FALSE by default and should be set to TRUE is logging is desired.
`verbose` | display infos & show progress bar

### Details

Short-term spectral analysis of the signal in <listOfFiles> using the Fast Fourier Transform and cepstral smoothing. Analysis results will be written to a file with the base name of the input file and '.css.' as extension. Default output is in SSFF format with 'css' in lower case as track name.

### Value

nrOfProcessedFiles or if only one file to process return AsspDataObj of that file

### Author(s)

Raphael Winkelmann

Lasse Bombien

### See Also

`dftSpectrum`, `lpsSpectrum`, `cepstrum`; all derived from libassp's spectrum function.

### Examples

    # get path to audio file
    path2wav <- list.files(system.file("extdata", package = "wrassp"),
                           pattern = glob2rx("*.wav"),
                           full.names = TRUE)[1]

    # calculate cepstrally smoothed spectrum
    res <- cssSpectrum(path2wav, toFile=FALSE)

    # plot spectral values at midpoint of signal
    plot(res$css[dim(res$css)[1]/2,],
         type='l',
         xlab='spectral value index',
         ylab='spectral value')

[Package wrassp version 0.1.4 Index]