In Opus's hybrid mode, which technology handles the audio spectrum frequencies above approximately 8 kHz?
Answer
The CELT-derived MDCT mode
The Opus hybrid mode dynamically switches compression techniques based on frequency range to leverage the strengths of both foundational codecs. Frequencies below approximately 8 kHz are managed by the SILK-derived LPC mode, which excels at modeling the characteristics of human speech for clarity at low bitrates. Conversely, frequencies above this threshold, extending up to the maximum bandwidth supported, are handled by the CELT-derived MDCT mode. This segmentation allows Opus to utilize CELT's strength in high-fidelity frequency domain processing for wider bandwidth audio components while retaining SILK's efficiency for core voice frequencies, enabling seamless transition without audible glitches.
Related Questions
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