Patent ID: 7460993

Claim:
A transform coder computer system for audio signal processing comprising: a transient detection component stored in computer system memory operating to process samples of an input signal to identify locations of transients in the input signal; an open-loop window configuration component stored in computer system memory operating in response to the identified transient location to configure a first configuration of sizes of a plurality of transform input windows over the input signal selected from at least a first window size, a second window size, and a third window size, so as to place one or more windows of the first window size to encompass a region of the input signal having at least one identified transient location and place windows of the second size in areas of the input signal having no identified transient locations; an encoding component stored in computer system memory for transform coding the input signal according to the first configuration of transform input window sizes, and for decoding to produce a reconstructed signal; a quality measurement component stored in computer system memory operating to measure achieved quality of the reconstructed signal; and a closed-loop window configuration component stored in computer system memory operating in response to the achieved quality measurement to adjust sizes of the transform input windows in the first configuration according to the achieved quality measurement to produce a second configuration of transform input windows for use in transform coding the input signal.