Improve physical geometry, fluid solvers, audio, and profiling

tools/audio_preview.py

@@ -0,0 +1,59 @@
+"""Create peak-normalized listening copies of PCM16 or float32 capture WAVs.
+
+Usage: py tools/audio_preview.py out/audio/single-450-baseline
+Original files retain calibration; preview levels must not be compared by source.
+"""
+import argparse
+import math
+from pathlib import Path
+import struct
+import wave
+
+
+def preview(path, destination):
+    data = path.read_bytes()
+    if data[:4] != b"RIFF" or data[8:12] != b"WAVE":
+        raise ValueError(f"Not a WAV: {path}")
+    offset = 12
+    fmt = payload = None
+    while offset + 8 <= len(data):
+        tag, size = struct.unpack_from("<4sI", data, offset)
+        chunk = data[offset + 8:offset + 8 + size]
+        if tag == b"fmt ":
+            fmt = struct.unpack_from("<HHIIHH", chunk)
+        elif tag == b"data":
+            payload = chunk
+        offset += 8 + size + size % 2
+    if fmt is None or payload is None:
+        raise ValueError(f"Missing WAV chunks: {path}")
+    encoding, channels, rate, _, _, bits = fmt
+    if (encoding, bits) == (3, 32):
+        values = [x[0] for x in struct.iter_unpack("<f", payload)]
+    elif (encoding, bits) == (1, 16):
+        values = [x[0] / 32768 for x in struct.iter_unpack("<h", payload)]
+    else:
+        raise ValueError(f"Unsupported WAV format: {path}")
+    if not all(math.isfinite(x) for x in values):
+        raise ValueError(f"Nonfinite audio: {path}")
+    peak = max(map(abs, values), default=0)
+    if peak == 0:
+        print(f"{path.name}: silent; no preview")
+        return
+    gain = 0.8 / peak
+    destination.mkdir(parents=True, exist_ok=True)
+    target = destination / (path.stem + "-preview.wav")
+    with wave.open(str(target), "wb") as out:
+        out.setparams((channels, 2, rate, 0, "NONE", "not compressed"))
+        out.writeframes(b"".join(struct.pack("<h", round(x * gain * 32767)) for x in values))
+    print(f"{target.name}: gain {20 * math.log10(gain):+.1f} dB")
+
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser(description=__doc__)
+    parser.add_argument("prefix", type=Path)
+    args = parser.parse_args()
+    paths = sorted(args.prefix.parent.glob(args.prefix.name + "-*.wav"))
+    if not paths:
+        parser.error("no matching capture WAVs")
+    for path in paths:
+        preview(path, args.prefix.parent / "previews")