/** The sample rate expected by the local Whisper runtime. */
export declare const WHISPER_SAMPLE_RATE = 16000;
/**
 * A channel-oriented Float32 PCM source. The channel arrays are borrowed and
 * are never modified by this module.
 */
export interface Float32PcmAudio {
    readonly sampleRate: number;
    readonly channelData: readonly Float32Array[];
}
/**
 * The small structural part of AudioBuffer used by this module. Keeping this
 * structural type local means the conversion logic is also usable in Node and
 * tests without depending on the DOM runtime.
 */
export interface AudioBufferLike {
    readonly sampleRate: number;
    readonly length: number;
    readonly numberOfChannels: number;
    getChannelData(channel: number): Float32Array;
}
export type PcmAudioInput = Float32PcmAudio | AudioBufferLike;
/**
 * Downmixes and linearly resamples an audio source to mono 16 kHz Float32
 * PCM. The source channel arrays are borrowed; only the returned output is
 * allocated.
 */
export declare function normalizeToWhisperPcm(input: PcmAudioInput): Float32Array;
/**
 * Encodes mono Float32 PCM as a little-endian PCM16 WAV. The samples are
 * clipped and non-finite values are encoded as silence. This function does
 * not resample; use {@link audioToPcm16Wav} for arbitrary input audio.
 */
export declare function encodePcm16Wav(samples: Float32Array, sampleRate?: number): Uint8Array;
/**
 * Converts an AudioBuffer-like object or channel-oriented Float32 PCM source
 * directly to a mono 16 kHz PCM16 WAV. The returned WAV is the only
 * full-audio-sized allocation made by this function.
 */
export declare function audioToPcm16Wav(input: PcmAudioInput): Uint8Array;
/** Convenience wrapper for a mono Float32 PCM stream. */
export declare function float32PcmToPcm16Wav(samples: Float32Array, sampleRate: number): Uint8Array;