  A brief review is provided of the use of the Square Wave Method (SWM) in the
field of signal and image analysis and it is specified how results thus
obtained are expressed using the Square Wave Transform (SWT), in the frequency
domain. To illustrate the new approach introduced in this field, the results of
two cases are analyzed: a) a sequence of samples (that is, measured values) of
an electromyographic recording; and b) the classic image of Lenna.
