#!/usr/bin/env python3 # -*- coding: utf-8 -*- """热场配乐合成：120 BPM / 30 bar / 60.000s，原创合成，无版权问题。""" import numpy as np, wave, os SR = 44100 BPM = 120 SPB = 60.0 / BPM # 0.5s BAR = 4 * SPB # 2.0s BARS = 30 DUR = BARS * BAR # 60.0s TAIL = 1.4 N = int(SR * (DUR + TAIL)) BUF = [np.zeros(N), np.zeros(N)] rng = np.random.default_rng(7) def T(bar, beat=0.0): return (bar * 4 + beat) * SPB def add(pos, sig, pan=0.0, gain=1.0): i = int(pos * SR) if i >= N: return j = min(N, i + len(sig)) s = sig[:j - i] * gain th = (pan + 1) * np.pi / 4 BUF[0][i:j] += s * np.cos(th) * 1.41421 BUF[1][i:j] += s * np.sin(th) * 1.41421 def tt(d): return np.arange(int(SR * d)) / SR def dec(d, tau, a=0.002): t = tt(d) e = np.exp(-t / tau) if a > 0: k = int(SR * a) if k > 1: e[:k] *= np.linspace(0, 1, k) return e def lp(x, cut): """指数 FIR 近似低通，cut 越小越暗""" k = max(2, int(0.5 + 1.0 / max(cut, 1e-4))) k = min(k, 900) ker = np.exp(-np.arange(k) / (k / 3.0)) ker /= ker.sum() return np.convolve(x, ker, mode="same") def hp(x): y = np.diff(x, prepend=x[0]) return y def saw(f, d, det=0.0): t = tt(d) if det: s = np.zeros(len(t)) for m in (1 - det, 1.0, 1 + det): s += 2 * ((t * f * m) % 1.0) - 1 return s / 3 return 2 * ((t * f) % 1.0) - 1 def sq(f, d): return np.sign(np.sin(2 * np.pi * f * tt(d))) # ---------------- 音色 ---------------- def kick(d=0.52, punch=1.0): t = tt(d) f = 48 + 118 * np.exp(-t / 0.028) ph = 2 * np.pi * np.cumsum(f) / SR body = np.sin(ph) * np.exp(-t / 0.105) clk = rng.normal(0, 1, len(t)) * np.exp(-t / 0.0022) * 0.5 s = body * 1.0 + clk * punch return np.tanh(s * 1.5) * 0.92 def snare(d=0.20): t = tt(d) n = rng.normal(0, 1, len(t)) n = hp(lp(n, 0.30)) * np.exp(-t / 0.055) tone = (np.sin(2 * np.pi * 195 * t) + np.sin(2 * np.pi * 278 * t)) * np.exp(-t / 0.035) return (n * 1.0 + tone * 0.45) * 0.55 def clap(d=0.26): out = np.zeros(int(SR * d)) for k, g in enumerate((0.7, 1.0, 0.85, 0.5)): o = int(SR * 0.0085 * k) t = tt(d - 0.0085 * k) n = hp(rng.normal(0, 1, len(t))) * np.exp(-t / (0.03 + 0.012 * k)) * g out[o:o + len(n)] += n return lp(out, 0.55) * 0.5 def hat(d=0.055, op=False): dd = 0.20 if op else d t = tt(dd) n = hp(hp(rng.normal(0, 1, len(t)))) return n * np.exp(-t / (0.055 if op else 0.014)) * 0.30 def ride(d=0.32): t = tt(d) n = hp(rng.normal(0, 1, len(t))) tone = sum(np.sin(2 * np.pi * f * t) for f in (3200, 4700, 6100)) / 3 return (n * 0.6 + tone * 0.4) * np.exp(-t / 0.10) * 0.16 def bass(f, d, bright=0.5): s = saw(f, d, 0.004) * 0.6 + np.sin(2 * np.pi * f * tt(d)) * 0.8 s = lp(s, 0.06 + 0.22 * bright) e = dec(d, d * 0.55, 0.004) return s * e * 0.6 def pluck(f, d, bright=1.0): s = saw(f, d, 0.010) * 0.7 + sq(f, d) * 0.3 s = lp(s, 0.10 + 0.40 * bright) return s * dec(d, d * 0.30, 0.003) * 0.34 def stab(freqs, d, bright=1.0): s = np.zeros(int(SR * d)) for f in freqs: s += saw(f, d, 0.013) s /= len(freqs) s = lp(s, 0.14 + 0.42 * bright) t = tt(d) e = np.exp(-t / (d * 0.42)) k = int(SR * 0.006); e[:k] *= np.linspace(0, 1, k) return s * e * 0.42 def pad(freqs, d, bright=0.35): s = np.zeros(int(SR * d)) for f in freqs: s += saw(f, d, 0.006) + saw(f * 2, d, 0.004) * 0.4 s /= len(freqs) s = lp(s, 0.02 + 0.10 * bright) t = tt(d) e = np.ones(len(t)) a = int(SR * 0.25); r = int(SR * 0.45) e[:a] = np.linspace(0, 1, a) e[-r:] = np.linspace(1, 0, r) return s * e * 0.30 def riser(d): t = tt(d); p = t / d n = rng.normal(0, 1, len(t)) sweep = np.zeros(len(t)) step = 2048 for i in range(0, len(t), step): c = 0.02 + 0.55 * (i / len(t)) ** 1.7 seg = n[i:i + step] sweep[i:i + step] = hp(lp(seg, max(c, 0.02))) f = 180 * 2 ** (p * 3.2) ph = 2 * np.pi * np.cumsum(f) / SR tone = np.sin(ph) * 0.35 env = p ** 2.2 return (sweep * 0.9 + tone) * env * 0.42 def impact(d=1.6): t = tt(d) f = 62 * np.exp(-t / 0.22) + 28 ph = 2 * np.pi * np.cumsum(f) / SR boom = np.sin(ph) * np.exp(-t / 0.34) cr = hp(rng.normal(0, 1, len(t))) * np.exp(-t / 0.42) * 0.30 return np.tanh((boom * 1.1 + cr) * 1.3) * 0.72 def crash(d=2.2): t = tt(d) n = hp(rng.normal(0, 1, len(t))) return n * np.exp(-t / 0.70) * 0.30 # ---------------- 和声 ---------------- # A minor: Am - F - C - G ROOT = [110.00, 87.31, 130.81, 98.00] TRI = [[220.00, 261.63, 329.63], [174.61, 220.00, 261.63], [261.63, 329.63, 392.00], [196.00, 246.94, 293.66]] def chord(bar): return bar % 4 # ---------------- 编排 ---------------- FULL = set(range(9, 20)) | set(range(26, 28)) KICKB = set(range(2, 20)) | set(range(23, 25)) | set(range(26, 30)) BREAK = set(range(20, 23)) for bar in range(BARS): ci = chord(bar) tri = TRI[ci]; root = ROOT[ci] b0 = T(bar) # --- pad：全程铺底 --- pg = 0.55 if bar in BREAK else (0.85 if bar in FULL else 0.6) add(b0, pad([tri[0] / 2, tri[1] / 2, tri[2] / 2], BAR * 1.02, 0.55 if bar in FULL else 0.3), 0.0, pg) # --- kick 四踩 --- if bar in KICKB: for b in range(4): g = 1.0 if bar in FULL else 0.72 add(T(bar, b), kick(), 0.0, g) if bar in FULL and bar % 4 == 3: add(T(bar, 3.5), kick(0.36, 0.6), 0.0, 0.8) # --- clap / snare 2&4 --- if bar >= 3 and bar not in BREAK: for b in (1, 3): add(T(bar, b), clap(), 0.06, 0.9 if bar in FULL else 0.6) if bar in FULL and bar % 2 == 1: add(T(bar, 3.75), snare(0.14), -0.15, 0.45) # --- hats 16分 --- if bar >= 1: for s in range(8): beat = s * 0.5 if bar in BREAK and s % 2 == 0: continue g = (0.9 if s % 2 else 0.45) * (1.0 if bar in FULL else 0.62) add(T(bar, beat + 0.25), hat(op=(s == 7 and bar % 4 == 3)), 0.22 if s % 2 else -0.18, g) # --- ride 点缀 --- if bar in FULL and bar % 2 == 0: for b in (0.5, 2.5): add(T(bar, b), ride(), 0.3, 0.7) # --- bass --- if bar in KICKB: pat = [(0, 0.5), (1, 0.5), (1.75, 0.25), (2, 0.5), (3, 0.5), (3.5, 0.5)] for b, ln in pat: f = root if b < 3 else root * (1.5 if bar % 2 else 1.0) add(T(bar, b), bass(f, ln * SPB * 0.95, 0.75 if bar in FULL else 0.4), 0.0, 1.0 if bar in FULL else 0.7) # --- arp 16分 --- if bar not in BREAK: seq = [0, 1, 2, 1, 2, 0, 1, 2] for s in range(8): f = tri[seq[s % len(seq)]] * (2 if (s in (4, 6) and bar in FULL) else 1) br = 1.0 if bar in FULL else (0.45 if bar < 5 else 0.7) g = 1.0 if bar in FULL else (0.5 if bar < 2 else 0.75) add(T(bar, s * 0.5), pluck(f, SPB * 0.48, br), -0.28 if s % 2 else 0.28, g) else: for s in (0, 3, 5): add(T(bar, s * 0.5 + 0.5), pluck(tri[s % 3] * 2, SPB * 0.9, 0.25), 0.2, 0.45) # --- 主音 stab --- if bar in FULL: add(T(bar, 0), stab([f * 2 for f in tri], SPB * 1.6, 1.0), 0.0, 0.85) if bar % 2 == 1: add(T(bar, 2.5), stab([f * 2 for f in tri], SPB * 0.9, 0.8), 0.1, 0.6) # --- riser / impact / crash --- add(T(7), riser(BAR * 2.0), 0.0, 0.85) # 进 drop add(T(9), impact(), 0.0, 1.0) add(T(9), crash(), 0.15, 0.9) add(T(15, 2), riser(BAR * 0.5), 0.0, 0.55) add(T(16), impact(1.0), 0.0, 0.7) add(T(16), crash(1.6), -0.15, 0.7) add(T(20), impact(1.8), 0.0, 0.95) # 进 breakdown（数据红线） add(T(20), crash(2.0), 0.0, 0.6) add(T(24), riser(BAR * 2.0), 0.0, 0.9) # 回升 add(T(26), impact(), 0.0, 1.0) # 终段 drop add(T(26), crash(), 0.15, 0.95) add(T(28), impact(1.9), 0.0, 0.9) # 收尾 add(T(28), crash(2.4), 0.0, 0.8) add(T(29, 2), crash(1.8), 0.0, 0.5) # ---------------- 母带 ---------------- out = [] for ch in BUF: x = ch # 侧链：kick 位置轻微压低 duck = np.ones(N) for bar in range(BARS): if bar not in KICKB: continue for b in range(4): i = int(T(bar, b) * SR) L = int(SR * 0.16) if i + L < N: duck[i:i + L] = np.minimum(duck[i:i + L], 0.62 + 0.38 * np.linspace(0, 1, L) ** 0.6) x = x * duck x = np.tanh(x * 0.62) / np.tanh(0.62) # 软限 out.append(x) # 尾部淡出 fo = int(SR * 1.0) for x in out: x[-fo:] *= np.linspace(1, 0, fo) x[:int(SR * 0.02)] *= np.linspace(0, 1, int(SR * 0.02)) peak = max(np.abs(out[0]).max(), np.abs(out[1]).max()) g = 0.90 / peak inter = np.empty(N * 2) inter[0::2] = out[0] * g inter[1::2] = out[1] * g pcm = (inter * 32767).astype("