Acoustic and Prosodic Discriminators for Zero-Shot Voice Cloning

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing text-to-speech (TTS) models struggle to achieve natural and expressive speech in zero-shot voice cloning due to the quality gap between zero-shot and few-shot systems, with neural networks making over-smooth predictions that fail to capture the diversity of human speech.

Innovation Solution

A multi-modal adversarial training framework is employed, utilizing two discriminators - an acoustic discriminator and a prosodic discriminator - to differentiate between synthesized and ground truth features, guiding the training of a TTS generator with an adversarial loss to improve acoustic and prosodic features.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If traditional TTS models are used for zero-shot voice cloning, then the system can generate speech without training data, but the speech quality is over-smooth and lacks natural expression

Engineering Contradiction:
Improvezero-shot capabilityVSAvoidspeech quality
Core Design Contradiction:
Adaptability or versatilityVSManufacturing precision

Solution Approach 1:

The speech generation task is segmented into two distinct discrimination tasks: acoustic feature discrimination and prosodic feature discrimination. This segmentation allows the model to separately optimize for different aspects of speech quality, preventing the over-smoothing effect that occurs when trying to optimize all features simultaneously in traditional zero-shot TTS models.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces a new dimension to the training objective by adding prosodic feature discrimination alongside acoustic feature discrimination. This multi-dimensional approach enables the model to capture both the spectral characteristics and the temporal/rhythmic characteristics of speech, thereby improving overall speech quality while maintaining zero-shot capability.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Stability of the object's composition

If neural networks make smooth predictions for speech synthesis, then the generation process is stable, but the diversity of human speech is not captured

Engineering Contradiction:
Improvegeneration stabilityVSAvoidspeech diversity
Core Design Contradiction:
Stability of the object's compositionVSAdaptability or versatility

Solution Approach 1:

The patent implements feedback mechanisms through discriminator models that provide gradient signals to the generator. The acoustic discriminator and prosodic discriminator separately evaluate different aspects of generated speech and provide targeted feedback, allowing the generator to maintain stability while capturing speech diversity through adversarial training.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent changes the parameter optimization landscape by introducing separate loss functions for acoustic features and prosodic features. This parameter differentiation allows the model to explore diverse speech patterns without sacrificing generation stability, as each parameter set is optimized independently through its corresponding discriminator.

Inventive Principle:
Principle #35Parameter changes

3Device complexity

If a single discriminator is used for TTS training, then the training process is simple, but both acoustic and prosodic features cannot be effectively differentiated

Engineering Contradiction:
Improvetraining framework complexityVSAvoidfeature discrimination accuracy
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The single discriminator is segmented into two specialized discriminators: an acoustic discriminator for spectral features and a prosodic discriminator for temporal/rhythmic features. This segmentation improves measurement precision by allowing each discriminator to specialize in specific feature types, while the overall training framework complexity remains manageable through modular architecture.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Each discriminator is designed with multi-functionality, handling both classification and feature extraction tasks. The acoustic discriminator processes mel-spectrogram features while the prosodic discriminator processes pitch and energy features, creating a universal framework that can differentiate multiple speech dimensions simultaneously without requiring separate specialized models for each function.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Data Source

PatentUS20250279085A1Multi-modal adversarial training for zero-shot voice cloning
Publication Date: 2025.09.04 ZOOM VIDEO COMM INC
  • US20250279085A1 patent drawing
  • US20250279085A1 patent drawing
  • US20250279085A1 patent drawing

AI summary

Systems and methods of multi-modal adversarial training for zero-shot voice cloning are provided. A communication platform provides training transcript data and training speaker data to a text-to-speech (TTS) model to obtains synthesized audio data comprising synthesized acoustic features and synthesized prosodic features. The communication platform determines determine a first classification prediction using a first discriminator model and a second classification prediction using a second discriminator model. The communication platform trains the first discriminator model and the second discriminator model based on the first classification prediction and the second classification prediction. The communication platform trains the TTS model to obtain a trained TTS model based on ground truth acoustic features, ground truth prosodic features, the synthesized acoustic features, the synthesized prosodic features, the first classification prediction, and the second classification prediction.