Frequency analysis method
First Claim
1. A frequency analysis method that simulates perception characteristics of human hearing, comprising the steps of:
- extracting from an input signal a sequence of blocks of discrete sampled values, wherein successive blocks of the sequence overlap each other in time;
concurrently windowing one of the successive blocks using a plurality of differing, symmetrical window functions of substantially identical length, each window function having a corresponding Fourier transform with a different bandwidth, to produce a plurality of windowed blocks of weighted sampled values; and
performing a Fourier transformation on each windowed block wherein for each windowed block at least one coefficient is generated having assigned thereto the bandwidth of the Fourier transform of the window function used to produce the windowed block, and wherein the at least one coefficient for each windowed block is chosen such that bandwidths assigned to the chosen coefficients of the plurality of windowed blocks adjoin one another approximately without gaps and in a manner approximately free from overlapping.
1 Assignment
0 Petitions
Accused Products
Abstract
A frequency analysis method comprises using a window function to evaluate aemporal input signal present in the form of discrete sampled values. The windowed input signal is subsequently subjected to Fourier transformation for the purpose of generating a set of coefficients. In order to develop such a method so that the characteristics of the human ear are simulated not only with respect to the spectral projection in the frequency range, but also with respect to the resolution in the temporal range, a set of different window functions is used to evaluate a block of the input signal in order to generate a set of blocks, weighted with the respective window functions, of sampled values whose Fourier transforms have different bandwidths, before each of the simultaneously generated blocks of sampled values is subjected to a dedicated Fourier transformation in such a way that for each window function at least respectively one coefficient is calculated which is assigned the bandwidth of the Fourier transforms of this window function, and that the coefficients are chosen such that the frequency bands assigned to them essentially adjoin one another.
156 Citations
7 Claims
-
1. A frequency analysis method that simulates perception characteristics of human hearing, comprising the steps of:
-
extracting from an input signal a sequence of blocks of discrete sampled values, wherein successive blocks of the sequence overlap each other in time; concurrently windowing one of the successive blocks using a plurality of differing, symmetrical window functions of substantially identical length, each window function having a corresponding Fourier transform with a different bandwidth, to produce a plurality of windowed blocks of weighted sampled values; and performing a Fourier transformation on each windowed block wherein for each windowed block at least one coefficient is generated having assigned thereto the bandwidth of the Fourier transform of the window function used to produce the windowed block, and wherein the at least one coefficient for each windowed block is chosen such that bandwidths assigned to the chosen coefficients of the plurality of windowed blocks adjoin one another approximately without gaps and in a manner approximately free from overlapping. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
Specification