Source file Mix.ml

(* Claude Code
 *
 * Copyright (C) 2026 Yoann Padioleau
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public License
 * (LGPL) as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 *)

(* See Mix.mli *)

let add (sounds : Signal.t list) : Signal.t =
  let n = List.fold_left (fun m s -> max m (Array.length s)) 0 sounds in
  let out = Array.make n 0. in
  List.iter (fun s -> Array.iteri (fun i x -> out.(i) <- out.(i) +. x) s) sounds;
  out

let gain (g : float) (s : Signal.t) : Signal.t = Array.map (fun x -> g *. x) s
let delay (seconds : float) (s : Signal.t) : Signal.t = Array.append (Array.make (Signal.samples seconds) 0.) s
let then_ (a : Signal.t) (b : Signal.t) : Signal.t = Array.append a b
let decibels (ratio : float) : float = 20. *. log10 ratio
let of_decibels (db : float) : float = 10. ** (db /. 20.)
let clip (x : float) : float = Float.max (-1.) (Float.min 1. x)
let soft_clip (x : float) : float = tanh x
let limit ?(soft = false) (s : Signal.t) : Signal.t = Array.map (if soft then soft_clip else clip) s