/**
 * Requantization, reordering, and stereo reconstruction.
 *
 * The Huffman stage produced integers. This stage turns them back into the
 * floating-point spectrum the encoder started from, undoing three things in
 * order:
 *
 * 1. **Requantization** — the encoder divided each line by a step size chosen
 *    per scalefactor band, then rounded. Reversing it applies `|x|^(4/3)` (the
 *    quantizer is a power law, not linear, because the ear's loudness response
 *    is) and multiplies by the band's step size back.
 * 2. **Reordering** — short blocks are transmitted grouped by scalefactor band,
 *    but the IMDCT needs them grouped by sub-band. The interleaving has to be
 *    undone before the transform.
 * 3. **Stereo reconstruction** — joint stereo transmits mid/side or an intensity
 *    position instead of left/right, because the two channels of real music are
 *    highly correlated and the difference signal is cheap to code.
 */
import type { GranuleInfo } from './sideinfo.js';
import type { Scalefactors } from './huffman.js';
/**
 * Converts quantized integers into the requantized spectrum.
 *
 * @param values 576 quantized lines from the Huffman stage.
 * @param out 576 requantized floats.
 */
export declare function requantize(values: Int32Array, granule: GranuleInfo, scalefactors: Scalefactors, sampleRate: number, nonZeroCount: number, out: Float32Array): void;
/**
 * Undoes the short-block interleaving.
 *
 * Transmitted order is scalefactor-band-major: band 0's three windows, then band
 * 1's three windows, and so on. The IMDCT needs sub-band-major order, where each
 * sub-band's 18 values are window 0's six lines, then window 1's, then window 2's.
 */
export declare function reorderShortBlock(spectrum: Float32Array, granule: GranuleInfo, sampleRate: number, scratch: Float32Array): void;
/**
 * Reconstructs left and right from a joint-stereo pair.
 *
 * Two independent mechanisms, which can both be active:
 *
 * - **MS (mid/side)**: the encoder sent `(L+R)/√2` and `(L-R)/√2`. Lossless, and
 *   very effective on centred material where the side signal is near-silent.
 * - **Intensity**: above some band the encoder discarded the side information
 *   entirely and sent only a stereo *position*. Both channels are rebuilt from
 *   the mid signal scaled by that position — lossy, and audible as a collapsed
 *   image if applied too low.
 */
export declare function applyJointStereo(left: Float32Array, right: Float32Array, modeExtension: number, granule: GranuleInfo, rightScalefactors: Scalefactors, sampleRate: number, nonZeroRight: number, isMpeg1: boolean): void;