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README.md
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@@ -76,7 +76,7 @@ The dataset contains an audiobook chapter level manifest with these fields:
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- **utterances.offset**: Offset of utterance within the chapter
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- **utterances.duration**: Duration of utterance
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Bandwidth is estimated from the first 30 seconds of each audiobook using the approach from [
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relative to the peak value of the spectrum, namely,
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$$f_{\text{max}} = \max\left\{f \in [0, f_{\text{Nyquist}}] \, \bigg|\, 10 \log_{10} \left(\frac{P(f)}{P_{\text{peak}}}\right) \geq -50\, \text{dB}\right\}$$
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where `P(f)` is the power spectral density and `P_peak` the maximum spectral power.
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- **utterances.offset**: Offset of utterance within the chapter
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- **utterances.duration**: Duration of utterance
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Bandwidth is estimated from the first 30 seconds of each audiobook using the approach from [Speech Data Processor (SDP) Toolkit](https://github.com/NVIDIA/NeMo-speech-data-processor/blob/main/sdp/processors/modify_manifest/data_to_data.py#L1259). The bandwidth fmax is estimated by using the mean of the power spectrum to find the highest frequency that has at least -50 dB level
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relative to the peak value of the spectrum, namely,
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$$f_{\text{max}} = \max\left\{f \in [0, f_{\text{Nyquist}}] \, \bigg|\, 10 \log_{10} \left(\frac{P(f)}{P_{\text{peak}}}\right) \geq -50\, \text{dB}\right\}$$
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where `P(f)` is the power spectral density and `P_peak` the maximum spectral power.
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