Papers › A Real-Time Wideband Neural Vocoder at 1.6 kb/s Using LPCNet

A Real-Time Wideband Neural Vocoder at 1.6 kb/s Using LPCNet

28 Mar 2019arXiv:1903.12087archive 2025-07-28

Jean-Marc Valin, Jan Skoglund

Neural speech synthesis algorithms are a promising new approach for coding speech at very low bitrate. They have so far demonstrated quality that far exceeds traditional vocoders, at the cost of very high complexity. In this work, we present a low-bitrate neural vocoder based on the LPCNet model. The use of linear prediction and sparse recurrent networks makes it possible to achieve real-time operation on general-purpose hardware. We demonstrate that LPCNet operating at 1.6 kb/s achieves significantly higher quality than MELP and that uncompressed LPCNet can exceed the quality of a waveform codec operating at low bitrate. This opens the way for new codec designs based on neural synthesis models.

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dump_layer_ignore mozilla/LPCNet/training_tf2/dump_lpcnet.py official repository unverified BSD-3-Clause (permissive) · 52188c0085750c07 · report
dump_sparse_gru mozilla/LPCNet/training_tf2/dump_lpcnet.py official repository unverified BSD-3-Clause (permissive) · 6e0af699c31a78db · report
dump_sparse_gru mozilla/LPCNet/training_tf2/keraslayerdump.py official repository unverified BSD-3-Clause (permissive) · 3874048af50f43b6 · report
interleave mozilla/LPCNet/training_tf2/lpcnet.py official repository unverified BSD-3-Clause (permissive) · 462214bb0c5c4921 · report
interp_mulaw mozilla/LPCNet/training_tf2/lossfuncs.py official repository unverified BSD-3-Clause (permissive) · a6e64cda1739e303 · report
lpc2rc mozilla/LPCNet/training_tf2/dataloader.py official repository unverified BSD-3-Clause (permissive) · 72b68e6945caf8ec · report
metric_icel mozilla/LPCNet/training_tf2/lossfuncs.py official repository unverified BSD-3-Clause (permissive) · 3d3bf2278d25692a · report
metric_oginterploss mozilla/LPCNet/training_tf2/lossfuncs.py official repository unverified BSD-3-Clause (permissive) · d9840947585808dc · report
printSparseVector mozilla/LPCNet/training_tf2/dump_lpcnet.py official repository unverified BSD-3-Clause (permissive) · 7437251d9a634f0b · report
printSparseVector mozilla/LPCNet/training_tf2/keraslayerdump.py official repository unverified BSD-3-Clause (permissive) · 3a4032c58aaadc9d · report
printVector mozilla/LPCNet/training_tf2/keraslayerdump.py official repository unverified BSD-3-Clause (permissive) · a228df437cb01d43 · report
quant_regularizer mozilla/LPCNet/training_tf2/lpcnet_plc.py official repository unverified BSD-3-Clause (permissive) · a1a9d70573973a74 · report
tree_to_pdf mozilla/LPCNet/training_tf2/lpcnet.py official repository unverified BSD-3-Clause (permissive) · 9e51f3aeba5a1306 · report
tree_to_pdf_train mozilla/LPCNet/training_tf2/lpcnet.py official repository unverified BSD-3-Clause (permissive) · 1f1e48ec8adf543a · report

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Speech Synthesis

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