Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A DNN Based Post-Filter to Enhance the Quality of Coded Speech in MDCT
  Domain   Frequency domain processing, and in particular the use of Modified Discrete
Cosine Transform (MDCT), is the most widespread approach to audio coding.
However, at low bitrates, audio quality, especially for speech, degrades
drastically due to the lack of available bits to directly code the transform
coefficients. Traditionally, post-filtering has been used to mitigate artefacts
in the coded speech by exploiting a-priori information of the source and extra
transmitted parameters. Recently, data-driven post-filters have shown better
results, but at the cost of significant additional complexity and delay. In
this work, we propose a mask-based post-filter operating directly in MDCT
domain of the codec, inducing no extra delay. The real-valued mask is applied
to the quantized MDCT coefficients and is estimated from a relatively
lightweight convolutional encoder-decoder network. Our solution is tested on
the recently standardized low-delay, low-complexity codec (LC3) at lowest
possible bitrate of 16 kbps. Objective and subjective assessments clearly show
the advantage of this approach over the conventional post-filter, with an
average improvement of 10 MUSHRA points over the LC3 coded speech.

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The categories of this paper are: plasm-ph
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The categories of this paper are: adap-org
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The categories of this paper are: econ
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The categories of this paper are: mtrl-th
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The categories of this paper are: nucl-ex
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The categories of this paper are: alg-geom
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The categories of this paper are: q-fin
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The categories of this paper are: chem-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: supr-con
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The categories of this paper are: physics
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The categories of this paper are: patt-sol
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The categories of this paper are: hep-lat
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The categories of this paper are: q-bio
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The categories of this paper are: solv-int
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The categories of this paper are: gr-qc