Detection of an audio signal transient using first and second maximum norms

摘要

Provided are, among other things, systems, methods and techniques for detecting whether a transient exists within an audio signal. According to one representative embodiment, a segment of a digital audio signal is divided into blocks, and a norm value is calculated for each of a number of the blocks, resulting in a set of norm values for such blocks, each such norm value representing a measure of signal strength within a corresponding block. A maximum norm value is then identified across such blocks, and a test criterion is applied to the norm values. If the test criterion is not satisfied, a first signal indicating that the segment does not include any transient is output, and if the test criterion is satisfied, a second signal indicating that the segment includes a transient is output. According to this embodiment, the test criterion involves a comparison of the maximum norm value to a different second maximum norm value, subject to a specified constraint, within the segment.

主权项

1. A method of detecting whether a transient exists within an audio signal, comprising:
using at least one processor to execute a set of steps that includes: dividing a segment of a digital audio signal into blocks; calculating a norm value for each of a plurality of the blocks, resulting in a set of norm values for the plurality of blocks, each said norm value representing a measure of signal strength within a corresponding block; identifying a maximum norm value across said plurality of the blocks; applying a test criterion to the norm values; if the test criterion is not satisfied, outputting a first signal indicating that the segment does not include any transient; and if the test criterion is satisfied, outputting a second signal indicating that the segment includes a transient, wherein the test criterion includes a comparison of the maximum norm value to a different second maximum norm value within the segment, and wherein said different second maximum norm value is determined based on at least one of: (1) a largest norm value prior to a spike that includes said maximum norm value and (2) a largest norm value within a sub-segment following said maximum norm value.