import type { KeystrokeEvent, KeystrokePack } from '../types.js';
export interface MixerOptions {
    keystrokes: KeystrokeEvent[];
    keystrokePack: KeystrokePack;
    keystrokeVolume: number;
    musicFile?: string;
    musicVolume: number;
    durationSec: number;
    audioDir: string;
    outputPath: string;
}
export interface MixerResult {
    audioPath: string;
    durationSec: number;
}
export declare function mixAudio(opts: MixerOptions): Promise<MixerResult>;