/** Width (px) of the sticky track-header column in the timeline. */
export declare const TRACK_HEADER_W = 160;
/** Pixel distance within which a dragged edge snaps to a candidate. */
export declare const SNAP_PX = 8;
/** Drag MIME prefix for bin items; suffixed with the item's media type so
 * lanes can accept/reject during dragover (data is unreadable until drop). */
export declare const BIN_ITEM_MIME_PREFIX = "application/x-timeline-bin-";
export declare function timeToPx(t: number, zoom: number): number;
export declare function pxToTime(px: number, zoom: number): number;
export declare function frameToPx(frame: number, fps: number, zoom: number): number;
export declare function pxToFrame(px: number, fps: number, zoom: number): number;
/**
 * Snap a time to the nearest candidate within threshold seconds. Returns the
 * original time when nothing is close enough.
 */
export declare function snap(t: number, candidates: number[], threshold: number): number;
/** Format a frame count as HH:MM:SS:FF at the given fps. */
export declare function formatTimecode(frame: number, fps: number): string;
/** Format seconds as a short duration label for clips/bin items (e.g. 12.5s). */
export declare function formatDuration(t: number): string;
export declare function groupColor(groupId: string): string;
/**
 * Pick a "nice" ruler tick interval for the current zoom so labels stay
 * readable (~target px apart).
 */
export declare function rulerInterval(zoom: number, targetPx?: number): number;