/**
 * Audio tracks play as AudioBufferSourceNodes in the synthesizer's own
 * AudioContext, so the recording and the MIDI share one sample clock. The only
 * way they can part is a transport change (play, pause, seek, tempo-free
 * rebuild), which shows up as a position error and is fixed by restarting the
 * source at the right offset.
 */
/** A playing source further than this from the MIDI position is restarted. */
export declare const AUDIO_RESTART_SECONDS = 0.03;
/** A recording that starts this soon after the playhead is scheduled sample-accurately. */
export declare const AUDIO_SCHEDULE_AHEAD_SECONDS = 0.5;
/** The MIDI clock counts as settled once it tracks the context clock this closely. */
export declare const MASTER_SETTLED_SECONDS = 0.01;
export type ClockSample = {
    contextTime: number;
    masterTime: number;
};
/**
 * The sequencer reports a lagging position for a few frames after it resumes.
 * Audio is started only once the MIDI clock advances in step with the context clock.
 */
export declare function isMasterClockSettled(previous: ClockSample | undefined, current: ClockSample): boolean;
export type AudioSyncInput = {
    /** MIDI transport time in seconds. */
    masterTime: number;
    /** True while the MIDI engine is actually advancing. */
    masterRunning: boolean;
    /** See isMasterClockSettled; starting waits for it, keeping and stopping do not. */
    masterSettled: boolean;
    /** Seconds into the MIDI where the recording starts (negative trims its start). */
    offset: number;
    /** Recording duration in seconds. */
    duration: number;
    /**
     * Where the current source is (or will be) in the recording now, or undefined
     * when no source is scheduled. May be negative for a source scheduled to start later.
     */
    sourcePosition: number | undefined;
};
export type AudioSyncPlan = {
    action: "stop";
} | {
    action: "keep";
}
/** Start a new source after `delay` seconds, `bufferOffset` seconds into the recording. */
 | {
    action: "start";
    delay: number;
    bufferOffset: number;
};
export declare function planAudioSync(input: AudioSyncInput): AudioSyncPlan;
/** Peak amplitude per bin across all channels, for drawing a waveform. */
export declare function computeWaveformPeaks(channels: readonly Float32Array[], binCount: number): Float32Array;