The Modified Discrete Cosine Transform: Its Implications for Audio Coding and Error Concealment
نویسنده
چکیده
This paper presents a study of the Modified Discrete Cosine Transform (MDCT) and its implications for audio coding and error concealment from the perspective of Fourier frequency analysis. A relationship between the MDCT and DFT via Shifted Discrete Fourier Transform (SDFT) is established, which provides a possible fast implementation of MDCT employing an FFT routine. The concept of Time Domain Alias Cancellation (TDAC), the symmetric and nonorthogonal properties of MDCT are analyzed and illustrated with intuitive examples. This study gives some new insights for innovative solutions in audio codec design and MDCT domain audio processing such as error concealment.
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