Patent ID: 7961937

Claim:
An apparatus for recognizing a pattern within input data, comprising: a processor configured to implement stages of the apparatus, including a segmentation stage configured to segment input data into a plurality of windows of data without applying a classification criterion to reject any of the windows; a normalization-independent classification stage configured to receive the plurality of windows of data but not the input data and apply at least one normalization-independent classification criterion predetermined from training data to each individual one of the plurality of windows and to reject any window that does not satisfy the at least one normalization-independent classification criterion, wherein the at least one normalization-independent classification criterion comprises, for each one of a plurality of predictive features of the criterion, comparing a linear combination of data values within a subject window to a fixed threshold of 0, such that a classification generated by applying the criterion to the subject window is independent of any uniform scaling of the subject window; a normalization stage configured to normalize the windows that were not rejected by the normalization-independent classification stage by scaling the corresponding input data to substantially equalize variance in the input data across a plurality of the non-rejected windows, and not to normalize the rejected windows; and a second classification stage configured to receive the plurality of variance-equalized non-rejected windows of data but not the input data and apply at least one normalization-dependent classification criterion to the normalized windows and to identify any window that satisfies the at least one normalization-dependent classification criterion.