Numerical Performance of Time-Frequency Transforms in Lossy Audio Coding
نویسنده
چکیده
Time-frequency analysis and the transforms that it gives rise to play an important role in digital signal processing. In lossy audio compression, for instance, it has been found that working in the transform domain leads to methods that achieve a much higher level of signal compression than could be achieved in the temporal domain. This article gives an introduction to time-frequency analysis through the basic theory of Fourier analysis, wavelets and Gabor frames. The results of a numerical investigation into lossy audio file compression comparing the discrete wavelet, Gabor and cosine transforms are then discussed.
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