A time-in noise cancellation filter with a variable transform size (Filter for time in aliasing cancellation with variable transform size)

摘要

The present invention relates to a time-domain noise canceling filter having a variable transform size, and more particularly, to a time-domain noise canceling filter having a variable transform size, comprising: a feature extracting unit for detecting whether there is a sudden change in an input audio signal; A conversion size determination unit for outputting a control signal for performing N / 2-point conversion if the feature extraction unit detects a sudden change in the audio signal, and N-point conversion if not; An N-point conversion unit for performing N-point MDCT conversion on input audio data; An N / 2 point conversion unit for performing N / 2-point MDCT conversion on the input audio data; And a switching unit for selectively supplying the input audio data to the N-point conversion unit or the N / 2-point conversion unit according to the control signal output from the conversion size determination unit. Therefore, the MDCT conversion is selectively performed by applying N-point conversion and N / 2-point conversion depending on whether there is a sudden change in the input audio data, thereby making it possible to faithfully reproduce a portion where a sudden change occurs.