/** Persisted discriminator for the normalized ActiveFrame runtime manifest. */
export declare const ACTIVE_FRAME_TYPE = "active-frame";
/** ActiveFrame runtime manifest version understood by this parser. */
export declare const ACTIVE_FRAME_VERSION = 1;
export interface AFFrame {
    o: number;
    l: number;
    t: number;
    ty: 'key' | 'delta';
    i: number;
    /** Exact decoded byte count for an independent `deflate-raw` or `raw` member. */
    uncompressedBytes?: number | undefined;
    data: Uint8Array;
    [key: string]: unknown;
}
export interface AFTrackManifest {
    type: typeof ACTIVE_FRAME_TYPE;
    version: typeof ACTIVE_FRAME_VERSION;
    codec: string;
    fps: number;
    totalFrames: number;
    width: number;
    height: number;
    gop: number;
    description?: string | undefined;
    frames: AFFrame[];
    role?: string;
    [key: string]: unknown;
}
export interface AFManifest extends AFTrackManifest {
    alpha?: AFTrackManifest;
}
export interface ParsedAF {
    manifest: AFManifest;
    frames: AFFrame[];
}
/**
 * Parse an `.af` ArrayBuffer into its manifest and per-frame byte slices.
 *
 * Each returned frame carries a `data` view — a zero-copy `Uint8Array` over the frame's
 * encoded bytes inside `buffer` — ready to feed to an `EncodedVideoChunk`. The `frames`
 * array is the same object as `manifest.frames` (each entry augmented in place with `data`).
 *
 * @param buffer - The full `.af` file contents.
 * @return The manifest and its frame list.
 */
export declare function parseAF(buffer: ArrayBuffer): ParsedAF;
/**
 * Fetch and parse an `.af` file.
 *
 * @param url - URL of the `.af` file.
 * @return The parsed container.
 */
export declare function loadAF(url: string): Promise<ParsedAF>;
/**
 * Index of the nearest keyframe at or before `index` (GOP-aware seek helper).
 *
 * @param manifest - A parsed `.af` manifest.
 * @param index - Frame index to seek from.
 * @return The keyframe index (0 if none found earlier).
 */
export declare function keyframeBefore(manifest: Pick<AFTrackManifest, 'frames'>, index: number): number;
/**
 * Decode a base64 codec-configuration string (avcC/hvcC) into the `Uint8Array` a
 * `VideoDecoder` expects as its `description`.
 *
 * @param base64 - Base64-encoded codec config box payload.
 * @return The raw config bytes.
 */
export declare function decodeDescription(base64: string): Uint8Array;