Neural Morphing: Sequence-Optimized Token-Level Morphing in Neural Audio Codecs

Emmanouil Karystinaios

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arXiv · 2607.12725

Neural Morphing: Sequence-Optimized Token-Level Morphing in Neural Audio Codecs

Emmanouil Karystinaios

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Abstract

Neural audio codecs were originally developed for high-fidelity compression; however, their latent token representations and expressive decoders also constitute a powerful substrate for controllable audio transformation. This work introduces Neural Morphing, a training-free token-domain audio effect that selects residual-vector-quantized (RVQ) token grains from a user palette and decodes the edited stream through a pretrained codec. The method combines an RVQ-group transfer policy that separates coarse, middle, and fine codebook groups with a continuity-constrained sequence matcher that replaces independent greedy selection with bounded beam search. The intended output is a controlled hybrid: the source preserves rhythmic organization while the palette contributes timbral color and residual detail. We focus on the implementation and realtime behavior of a deployable VST3/AU system, including chunked rendering, palette-size scaling, and backend health checks.

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BibTeX RIS

Emmanouil Karystinaios. 2026-08-04. Neural Morphing: Sequence-Optimized Token-Level Morphing in Neural Audio Codecs. https://arxiv.org/abs/2607.12725

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