The present invention provides apparatus, methods, and computer program
products that can decrease the latency with which the coefficients of a
function representative of signal are determined. Specifically, the
apparatus, methods, and computer program products of the present
invention, taking advantage of the independence of samples, updates each
of the coefficients of the function as each sample is received. As such,
when the final sample is received, the apparatus, methods, and computer
program products of the present invention need only update each
coefficient with the contribution of the last sample prior to outputting
the coefficients. As such, the latency from the time the last sample is
received and the availability of the coefficients is decreased. To
further decrease the latency, in one embodiment, the apparatus, methods,
and computer program products of the present invention prestore either
all or a portion of the possible values of the contribution of a sample
to each coefficient, such that. As such, when the sample is received, the
apparatus, methods, and computer program products of the present
invention evaluate the value of the sample and retrieve the appropriate
value from the prestored values that corresponds to the coefficient,
sample, and value of the sample, thereby decreasing the time required to
determine the coefficients. The apparatus, methods, and computer program
products of the present invention also allow individual or subsets of the
coefficients to be observed and also allow individual or subsets of the
coefficients to be determined in varying resolutions.