CSIGIN

CSIGIN - read signal (overlapping frames)

Usage:

CSIGIN sig rev l s k d

Inputs:

sig

The name of the shell wave item. There is no default.

rev

The reverse read direction. The following values are supported:

NO|0 - do not reverse the read direction. This is the default.

YES|1 - read the file in backwards.

l

The frame length in samples (l >= 4). The default is 1024.

s

The frame shift in samples (1 <= s <= l). The default is l/4.

k

The amplification factor. The default is 1.

d

The differentiation factor (0 <= d <= 1).

Outputs:

xi

The signal of channel i (l samples).

sr

The sampling rate in Hz.

n

The number of frames.

i

The frame counter (0..n).

Function:

This atom implements a signal-frame read function for analysis methods. In each cycle a frame with l samples is read from the wave-item and then the read position is incremented by s samples. In order to centre the signal in the frame (read-position = centre of frame), zero-signals are appended to the beginning and end of the wave-item. The picture below shows how the signal is split into analysis frames.

Signal-frame read function.This read function is used by most of the signal analysis methods. The values of the outputs sr and n are set during the initialisation. The output l is initialised with 0 and incremented by 1 after each read cycle. The input rev can be used to reverse the signal in time.