On Properties, Relations, and Simplified Implementation of Filter Banks in the Dolby Digital (Plus) AC-3 Audio Coding Standards

@article{Britanak2011OnPR,
  title={On Properties, Relations, and Simplified Implementation of Filter Banks in the Dolby Digital (Plus) AC-3 Audio Coding Standards},
  author={Vladimir Britanak},
  journal={IEEE Transactions on Audio, Speech, and Language Processing},
  year={2011},
  volume={19},
  pages={1231-1241}
}
  • V. Britanak
  • Published 1 July 2011
  • Computer Science
  • IEEE Transactions on Audio, Speech, and Language Processing
The Dolby Digital (Plus) AC-3 audio coding standards are currently the key enabling technologies for high-quality compression and decompression of digital audio signals. The Dolby Digital (Plus) AC-3 audio coding standards have adopted the modified discrete cosine transform (MDCT) for the time/frequency transformation of an audio data block. Besides a long transform being the MDCT, the AC-3 defines additional two variants of cosine-modulated filter banks called the first and second short… 
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  • 2012
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A fast conversion algorithm is presented to convert the frequency coefficients of the long (MDCT) transform to those of two short transforms and vice versa, directly in the frequency domain, thus minimizing the amount of partial decoding/encoding and memory requirements during the conversion and transcoding processes.
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The proposed time-frequency hybrid downmixing method for AC-3 decoding does not need frequency coefficients conversion between long and short blocks, and has approximately 26% and 32% reduction in numbers of additions and multiplications, respectively.

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