/**
 * Voice tone analysis utilities
 */
export interface VoiceAnalysisResult {
    pitch: number;
    speed: number;
    energy: number;
    emotion: 'calm' | 'excited' | 'stressed' | 'neutral';
    confidence: number;
}
/**
 * Analyze voice tone from audio stream
 */
export declare function analyzeVoiceTone(audioStream: MediaStream): Promise<VoiceAnalysisResult>;
/**
 * Start continuous voice monitoring
 */
export declare class VoiceMonitor {
    private audioContext;
    private analyser;
    private microphone;
    private animationFrame;
    private callback;
    start(stream: MediaStream, callback: (result: VoiceAnalysisResult) => void): Promise<void>;
    private analyze;
    stop(): void;
}