#!/usr/bin/env python3 """Sample-accurate SFX track for the Fable explainer. Synthesizes pops/ticks/whooshes/thumps/chimes procedurally and places them at the exact times the deterministic engine animates — one 54s stereo WAV out. """ import math, wave, struct, random SR = 48000 TOTAL = 54.0 random.seed(7) def env_exp(n, k): return [math.exp(-k * i / SR) for i in range(n)] def pop(gain=1.0): n = int(0.10 * SR); out = [] for i in range(n): t = i / SR f = 320 - 170 * (i / n) out.append(gain * math.sin(2 * math.pi * f * t) * math.exp(-t * 42)) return out def tick(gain=1.0): n = int(0.03 * SR); out = [] for i in range(n): t = i / SR s = math.sin(2 * math.pi * 1900 * t) + 0.3 * (random.random() * 2 - 1) out.append(gain * 0.7 * s * math.exp(-t * 220)) return out def whoosh(gain=1.0, dur=0.35): n = int(dur * SR); raw = [(random.random() * 2 - 1) for _ in range(n)] # cheap lowpass: moving average out = []; acc = 0.0; K = 9 for i in range(n): acc += raw[i] if i >= K: acc -= raw[i - K] e = math.sin(math.pi * i / n) ** 2 out.append(gain * 0.5 * (acc / K) * e) return out def thump(gain=1.0): n = int(0.16 * SR); out = [] for i in range(n): t = i / SR s = math.sin(2 * math.pi * 88 * t) + 0.2 * math.sin(2 * math.pi * 176 * t) out.append(gain * s * math.exp(-t * 28)) return out def chime(gain=1.0): n = int(0.6 * SR); out = [] for i in range(n): t = i / SR s = 0.6 * math.sin(2 * math.pi * 660 * t) + 0.4 * math.sin(2 * math.pi * 990 * t) out.append(gain * 0.5 * s * math.exp(-t * 7)) return out GEN = {"pop": pop, "tick": tick, "whoosh": whoosh, "thump": thump, "chime": chime} INTRO = 2.6; BEAT = 6.0 def B(i): return INTRO + i * BEAT # beat i start events = [] def ev(t, kind, g=1.0): events.append((t, kind, g)) # intro ev(0.15, "pop", 0.8); ev(0.55, "tick", 0.7); ev(0.85, "whoosh", 0.5) # beat boundaries: wipe whooshes for i in range(9): ev(B(i) - 0.14, "whoosh", 0.45) # b1 FABLE ev(B(0) + 0.20, "pop", 0.9); ev(B(0) + 0.55, "thump", 0.5); ev(B(0) + 1.20, "tick", 0.8); ev(B(0) + 1.75, "tick", 0.4) # b2 RUNS LONG (dots tick along the line) ev(B(1) + 0.20, "pop", 0.9); ev(B(1) + 0.60, "thump", 0.6); ev(B(1) + 1.10, "tick", 0.7) for k in range(5): ev(B(1) + 1.45 + k * 0.55, "tick", 0.45) # b3 SAY LESS -> GET MORE ev(B(2) + 0.35, "pop", 0.9); ev(B(2) + 0.90, "tick", 0.7) ev(B(2) + 1.10, "whoosh", 0.6); ev(B(2) + 1.80, "thump", 0.8); ev(B(2) + 2.55, "tick", 0.4) # b4 REMOVE SCAFFOLDING (guides vanish) ev(B(3) + 0.45, "pop", 0.9); ev(B(3) + 0.80, "tick", 0.7) for k in range(4): ev(B(3) + 1.55 + k * 0.5, "tick", 0.5) ev(B(3) + 2.45, "tick", 0.4) # b5 IN PARALLEL ev(B(4) + 0.30, "pop", 0.9); ev(B(4) + 0.75, "thump", 0.6); ev(B(4) + 1.20, "whoosh", 0.7) ev(B(4) + 1.50, "tick", 0.7) for k in range(3): ev(B(4) + 2.25 + k * 0.18, "tick", 0.5) # b6 MORE OUTPUT (bars land) ev(B(5) + 0.45, "pop", 0.9); ev(B(5) + 1.05, "tick", 0.7); ev(B(5) + 1.40, "whoosh", 0.6) for k in range(3): ev(B(5) + 2.10 + k * 0.35, "thump", 0.55) # b7 DONT MICROMANAGE (knob ticks fade, plane whoosh) ev(B(6) + 0.35, "pop", 0.9); ev(B(6) + 0.95, "tick", 0.7) for k in range(3): ev(B(6) + 1.30 + k * 0.4, "tick", 0.4) ev(B(6) + 2.80, "whoosh", 0.7) # b8 TRUST THE BRIEF ev(B(7) + 0.35, "pop", 0.9); ev(B(7) + 0.85, "thump", 0.7); ev(B(7) + 1.75, "chime", 0.8) # outro ev(B(8) + 0.15, "pop", 0.7); ev(B(8) + 0.55, "tick", 0.6); ev(B(8) + 1.15, "chime", 0.6) # ---- mixdown ---- N = int(TOTAL * SR) buf = [0.0] * N for t, kind, g in events: smp = GEN[kind](g) i0 = int(t * SR) for j, v in enumerate(smp): idx = i0 + j if 0 <= idx < N: buf[idx] += v # master gain + soft clip peak = max(abs(v) for v in buf) or 1.0 norm = min(1.0, 0.85 / peak) OUT = "/Users/davendrapatel/videoclaw/projects/fable-explainer/artifacts/audio/sfx-54s.wav" with wave.open(OUT, "wb") as w: w.setnchannels(2); w.setsampwidth(2); w.setframerate(SR) frames = bytearray() for v in buf: s = int(max(-1.0, min(1.0, v * norm)) * 32767) frames += struct.pack("