window
Applies a given window shape to a vector stored in an array. The output is an array with the windowed vector.
Syntax
kout[] window kin[] [, koff, itype]
Initialization
itype -- optional window type: 0 = Hamming, 1 = Hanning (von Hann) (defaults to 1).
kout[] -- output array containing the windowed output. It will be created if it does not exist.
kin[] -- input array containing the input vector.
koff -- offset to make window start at position koff (non-negative only, defaults to 0).
Examples
Here is an example of the window opcode. It uses the file window.csd.
| Example of the window opcode. |
|---|
| <CsoundSynthesizer>
<CsOptions>
-d -o dac
</CsOptions>
<CsInstruments>
;ksmps needs to be an integer div of hopsize
ksmps = 64
instr 1
ihopsize = 256 ; hopsize
ifftsize = 1024 ; FFT size
iolaps = ifftsize/ihopsize ; overlaps
ibw = sr/ifftsize ; bin bandwidth
kcnt init 0 ; counting vars
krow init 0
kOla[] init ifftsize ; overlap-add buffer
kIn[] init ifftsize ; input buffer
kOut[][] init iolaps, ifftsize ; output buffers
a1 diskin2 "fox.wav",1,0,1 ; audio input
/* every hopsize samples */
if kcnt == ihopsize then
/* window and take FFT */
kWin[] window kIn,krow*ihopsize
kSpec[] rfft kWin
/* filter between high and low freqs */
ilow = 0
ihigh = 1000
ki = int(ilow/ibw)
until ki == int(ihigh/ibw) do
kSpec[ki] = 0
ki += 1
od
/* IFFT + window */
kRow[] rifft kSpec
kWin window kRow, krow*ihopsize
/* place it on out buffer */
kOut setrow kWin, krow
/* zero the ola buffer */
kOla = 0
/* overlap-add */
ki = 0
until ki == iolaps do
kRow getrow kOut, ki
kOla = kOla + kRow
ki += 1
od
/* update counters */
krow = (krow+1)%iolaps
kcnt = 0
endif
/* shift audio in/out of buffers */
kIn shiftin a1
a2 shiftout kOla
out a2/iolaps
/* increment counter */
kcnt += ksmps
endin
</CsInstruments>
<CsScore>
i1 0 10
</CsScore>
</CsoundSynthesizer>
|
See Also
Vectorial opcodes
array opcodes
Array-based spectral opcodes
Credits
Author: Victor Lazzarini
NUI Maynooth
2014
New in version 6.04