46 lines
1.2 KiB
Python
46 lines
1.2 KiB
Python
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"""PCM 归一化与 WAV 封装。"""
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from __future__ import annotations
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import array
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import pytest
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from app.services.audio_wav import (
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WavDecodeError,
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normalize_pcm_s16le_for_baidu,
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pcm_s16le_to_wav_bytes,
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wav_bytes_to_pcm16k_mono_s16le,
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)
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def test_normalize_boosts_quiet_pcm() -> None:
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samples = array.array("h", [50, -80, 30] * 500)
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pcm = samples.tobytes()
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out = normalize_pcm_s16le_for_baidu(pcm)
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arr = array.array("h")
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arr.frombytes(out)
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assert max(abs(x) for x in arr) > max(abs(x) for x in samples)
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def test_normalize_skips_loud_pcm() -> None:
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samples = array.array("h", [15000, -14000])
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pcm = samples.tobytes()
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out = normalize_pcm_s16le_for_baidu(pcm)
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assert out == pcm
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def test_pcm_wav_roundtrip_is_valid_wav() -> None:
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pcm = array.array("h", [100, -200, 300] * 100).tobytes()
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wav = pcm_s16le_to_wav_bytes(pcm)
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back = wav_bytes_to_pcm16k_mono_s16le(wav)
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assert len(back) == len(pcm)
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assert max(abs(x) for x in array.array("h", back)) >= max(
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abs(x) for x in array.array("h", pcm)
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)
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def test_pcm_s16le_to_wav_empty_raises() -> None:
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with pytest.raises(WavDecodeError):
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pcm_s16le_to_wav_bytes(b"")
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