742 lines
22 KiB
Python
742 lines
22 KiB
Python
|
"""
|
||
|
Module to read / write wav files using NumPy arrays
|
||
|
|
||
|
Functions
|
||
|
---------
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||
|
`read`: Return the sample rate (in samples/sec) and data from a WAV file.
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||
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|
`write`: Write a NumPy array as a WAV file.
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||
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"""
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||
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import sys
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||
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import numpy
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||
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import struct
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||
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import warnings
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||
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from enum import IntEnum
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||
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||
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__all__ = [
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'WavFileWarning',
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'read',
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||
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'write'
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]
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class WavFileWarning(UserWarning):
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pass
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class WAVE_FORMAT(IntEnum):
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||
|
"""
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||
|
WAVE form wFormatTag IDs
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||
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|
Complete list is in mmreg.h in Windows 10 SDK. ALAC and OPUS are the
|
||
|
newest additions, in v10.0.14393 2016-07
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||
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"""
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UNKNOWN = 0x0000
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PCM = 0x0001
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ADPCM = 0x0002
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IEEE_FLOAT = 0x0003
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VSELP = 0x0004
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||
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IBM_CVSD = 0x0005
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ALAW = 0x0006
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MULAW = 0x0007
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DTS = 0x0008
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DRM = 0x0009
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WMAVOICE9 = 0x000A
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WMAVOICE10 = 0x000B
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||
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OKI_ADPCM = 0x0010
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||
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DVI_ADPCM = 0x0011
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||
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IMA_ADPCM = 0x0011 # Duplicate
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||
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MEDIASPACE_ADPCM = 0x0012
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||
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SIERRA_ADPCM = 0x0013
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||
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G723_ADPCM = 0x0014
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||
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DIGISTD = 0x0015
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||
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DIGIFIX = 0x0016
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||
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DIALOGIC_OKI_ADPCM = 0x0017
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||
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MEDIAVISION_ADPCM = 0x0018
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||
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CU_CODEC = 0x0019
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||
|
HP_DYN_VOICE = 0x001A
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||
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YAMAHA_ADPCM = 0x0020
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||
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SONARC = 0x0021
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||
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DSPGROUP_TRUESPEECH = 0x0022
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||
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ECHOSC1 = 0x0023
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||
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AUDIOFILE_AF36 = 0x0024
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||
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APTX = 0x0025
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||
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AUDIOFILE_AF10 = 0x0026
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PROSODY_1612 = 0x0027
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LRC = 0x0028
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DOLBY_AC2 = 0x0030
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GSM610 = 0x0031
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MSNAUDIO = 0x0032
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ANTEX_ADPCME = 0x0033
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||
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CONTROL_RES_VQLPC = 0x0034
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DIGIREAL = 0x0035
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DIGIADPCM = 0x0036
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CONTROL_RES_CR10 = 0x0037
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NMS_VBXADPCM = 0x0038
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CS_IMAADPCM = 0x0039
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ECHOSC3 = 0x003A
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ROCKWELL_ADPCM = 0x003B
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ROCKWELL_DIGITALK = 0x003C
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XEBEC = 0x003D
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G721_ADPCM = 0x0040
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||
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G728_CELP = 0x0041
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||
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MSG723 = 0x0042
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INTEL_G723_1 = 0x0043
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INTEL_G729 = 0x0044
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||
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SHARP_G726 = 0x0045
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MPEG = 0x0050
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RT24 = 0x0052
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PAC = 0x0053
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MPEGLAYER3 = 0x0055
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LUCENT_G723 = 0x0059
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CIRRUS = 0x0060
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ESPCM = 0x0061
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VOXWARE = 0x0062
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||
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CANOPUS_ATRAC = 0x0063
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G726_ADPCM = 0x0064
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G722_ADPCM = 0x0065
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DSAT = 0x0066
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DSAT_DISPLAY = 0x0067
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VOXWARE_BYTE_ALIGNED = 0x0069
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VOXWARE_AC8 = 0x0070
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VOXWARE_AC10 = 0x0071
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VOXWARE_AC16 = 0x0072
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VOXWARE_AC20 = 0x0073
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VOXWARE_RT24 = 0x0074
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||
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VOXWARE_RT29 = 0x0075
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||
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VOXWARE_RT29HW = 0x0076
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||
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VOXWARE_VR12 = 0x0077
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VOXWARE_VR18 = 0x0078
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VOXWARE_TQ40 = 0x0079
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VOXWARE_SC3 = 0x007A
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VOXWARE_SC3_1 = 0x007B
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SOFTSOUND = 0x0080
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||
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VOXWARE_TQ60 = 0x0081
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MSRT24 = 0x0082
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G729A = 0x0083
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MVI_MVI2 = 0x0084
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DF_G726 = 0x0085
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DF_GSM610 = 0x0086
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ISIAUDIO = 0x0088
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ONLIVE = 0x0089
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MULTITUDE_FT_SX20 = 0x008A
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||
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INFOCOM_ITS_G721_ADPCM = 0x008B
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||
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CONVEDIA_G729 = 0x008C
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||
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CONGRUENCY = 0x008D
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SBC24 = 0x0091
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DOLBY_AC3_SPDIF = 0x0092
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MEDIASONIC_G723 = 0x0093
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PROSODY_8KBPS = 0x0094
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||
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ZYXEL_ADPCM = 0x0097
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PHILIPS_LPCBB = 0x0098
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||
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PACKED = 0x0099
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|
MALDEN_PHONYTALK = 0x00A0
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||
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RACAL_RECORDER_GSM = 0x00A1
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||
|
RACAL_RECORDER_G720_A = 0x00A2
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RACAL_RECORDER_G723_1 = 0x00A3
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RACAL_RECORDER_TETRA_ACELP = 0x00A4
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NEC_AAC = 0x00B0
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RAW_AAC1 = 0x00FF
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||
|
RHETOREX_ADPCM = 0x0100
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|
IRAT = 0x0101
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||
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VIVO_G723 = 0x0111
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VIVO_SIREN = 0x0112
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PHILIPS_CELP = 0x0120
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||
|
PHILIPS_GRUNDIG = 0x0121
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||
|
DIGITAL_G723 = 0x0123
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SANYO_LD_ADPCM = 0x0125
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SIPROLAB_ACEPLNET = 0x0130
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SIPROLAB_ACELP4800 = 0x0131
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SIPROLAB_ACELP8V3 = 0x0132
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SIPROLAB_G729 = 0x0133
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||
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SIPROLAB_G729A = 0x0134
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||
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SIPROLAB_KELVIN = 0x0135
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||
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VOICEAGE_AMR = 0x0136
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||
|
G726ADPCM = 0x0140
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||
|
DICTAPHONE_CELP68 = 0x0141
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||
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DICTAPHONE_CELP54 = 0x0142
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QUALCOMM_PUREVOICE = 0x0150
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QUALCOMM_HALFRATE = 0x0151
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|
TUBGSM = 0x0155
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|
MSAUDIO1 = 0x0160
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|
WMAUDIO2 = 0x0161
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||
|
WMAUDIO3 = 0x0162
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||
|
WMAUDIO_LOSSLESS = 0x0163
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||
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WMASPDIF = 0x0164
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||
|
UNISYS_NAP_ADPCM = 0x0170
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||
|
UNISYS_NAP_ULAW = 0x0171
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||
|
UNISYS_NAP_ALAW = 0x0172
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||
|
UNISYS_NAP_16K = 0x0173
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||
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SYCOM_ACM_SYC008 = 0x0174
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||
|
SYCOM_ACM_SYC701_G726L = 0x0175
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||
|
SYCOM_ACM_SYC701_CELP54 = 0x0176
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||
|
SYCOM_ACM_SYC701_CELP68 = 0x0177
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||
|
KNOWLEDGE_ADVENTURE_ADPCM = 0x0178
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||
|
FRAUNHOFER_IIS_MPEG2_AAC = 0x0180
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||
|
DTS_DS = 0x0190
|
||
|
CREATIVE_ADPCM = 0x0200
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||
|
CREATIVE_FASTSPEECH8 = 0x0202
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||
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CREATIVE_FASTSPEECH10 = 0x0203
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||
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UHER_ADPCM = 0x0210
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||
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ULEAD_DV_AUDIO = 0x0215
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||
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ULEAD_DV_AUDIO_1 = 0x0216
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QUARTERDECK = 0x0220
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||
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ILINK_VC = 0x0230
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||
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RAW_SPORT = 0x0240
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||
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ESST_AC3 = 0x0241
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||
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GENERIC_PASSTHRU = 0x0249
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||
|
IPI_HSX = 0x0250
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||
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IPI_RPELP = 0x0251
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||
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CS2 = 0x0260
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||
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SONY_SCX = 0x0270
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||
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SONY_SCY = 0x0271
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||
|
SONY_ATRAC3 = 0x0272
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||
|
SONY_SPC = 0x0273
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||
|
TELUM_AUDIO = 0x0280
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||
|
TELUM_IA_AUDIO = 0x0281
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||
|
NORCOM_VOICE_SYSTEMS_ADPCM = 0x0285
|
||
|
FM_TOWNS_SND = 0x0300
|
||
|
MICRONAS = 0x0350
|
||
|
MICRONAS_CELP833 = 0x0351
|
||
|
BTV_DIGITAL = 0x0400
|
||
|
INTEL_MUSIC_CODER = 0x0401
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||
|
INDEO_AUDIO = 0x0402
|
||
|
QDESIGN_MUSIC = 0x0450
|
||
|
ON2_VP7_AUDIO = 0x0500
|
||
|
ON2_VP6_AUDIO = 0x0501
|
||
|
VME_VMPCM = 0x0680
|
||
|
TPC = 0x0681
|
||
|
LIGHTWAVE_LOSSLESS = 0x08AE
|
||
|
OLIGSM = 0x1000
|
||
|
OLIADPCM = 0x1001
|
||
|
OLICELP = 0x1002
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||
|
OLISBC = 0x1003
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||
|
OLIOPR = 0x1004
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||
|
LH_CODEC = 0x1100
|
||
|
LH_CODEC_CELP = 0x1101
|
||
|
LH_CODEC_SBC8 = 0x1102
|
||
|
LH_CODEC_SBC12 = 0x1103
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||
|
LH_CODEC_SBC16 = 0x1104
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||
|
NORRIS = 0x1400
|
||
|
ISIAUDIO_2 = 0x1401
|
||
|
SOUNDSPACE_MUSICOMPRESS = 0x1500
|
||
|
MPEG_ADTS_AAC = 0x1600
|
||
|
MPEG_RAW_AAC = 0x1601
|
||
|
MPEG_LOAS = 0x1602
|
||
|
NOKIA_MPEG_ADTS_AAC = 0x1608
|
||
|
NOKIA_MPEG_RAW_AAC = 0x1609
|
||
|
VODAFONE_MPEG_ADTS_AAC = 0x160A
|
||
|
VODAFONE_MPEG_RAW_AAC = 0x160B
|
||
|
MPEG_HEAAC = 0x1610
|
||
|
VOXWARE_RT24_SPEECH = 0x181C
|
||
|
SONICFOUNDRY_LOSSLESS = 0x1971
|
||
|
INNINGS_TELECOM_ADPCM = 0x1979
|
||
|
LUCENT_SX8300P = 0x1C07
|
||
|
LUCENT_SX5363S = 0x1C0C
|
||
|
CUSEEME = 0x1F03
|
||
|
NTCSOFT_ALF2CM_ACM = 0x1FC4
|
||
|
DVM = 0x2000
|
||
|
DTS2 = 0x2001
|
||
|
MAKEAVIS = 0x3313
|
||
|
DIVIO_MPEG4_AAC = 0x4143
|
||
|
NOKIA_ADAPTIVE_MULTIRATE = 0x4201
|
||
|
DIVIO_G726 = 0x4243
|
||
|
LEAD_SPEECH = 0x434C
|
||
|
LEAD_VORBIS = 0x564C
|
||
|
WAVPACK_AUDIO = 0x5756
|
||
|
OGG_VORBIS_MODE_1 = 0x674F
|
||
|
OGG_VORBIS_MODE_2 = 0x6750
|
||
|
OGG_VORBIS_MODE_3 = 0x6751
|
||
|
OGG_VORBIS_MODE_1_PLUS = 0x676F
|
||
|
OGG_VORBIS_MODE_2_PLUS = 0x6770
|
||
|
OGG_VORBIS_MODE_3_PLUS = 0x6771
|
||
|
ALAC = 0x6C61
|
||
|
_3COM_NBX = 0x7000 # Can't have leading digit
|
||
|
OPUS = 0x704F
|
||
|
FAAD_AAC = 0x706D
|
||
|
AMR_NB = 0x7361
|
||
|
AMR_WB = 0x7362
|
||
|
AMR_WP = 0x7363
|
||
|
GSM_AMR_CBR = 0x7A21
|
||
|
GSM_AMR_VBR_SID = 0x7A22
|
||
|
COMVERSE_INFOSYS_G723_1 = 0xA100
|
||
|
COMVERSE_INFOSYS_AVQSBC = 0xA101
|
||
|
COMVERSE_INFOSYS_SBC = 0xA102
|
||
|
SYMBOL_G729_A = 0xA103
|
||
|
VOICEAGE_AMR_WB = 0xA104
|
||
|
INGENIENT_G726 = 0xA105
|
||
|
MPEG4_AAC = 0xA106
|
||
|
ENCORE_G726 = 0xA107
|
||
|
ZOLL_ASAO = 0xA108
|
||
|
SPEEX_VOICE = 0xA109
|
||
|
VIANIX_MASC = 0xA10A
|
||
|
WM9_SPECTRUM_ANALYZER = 0xA10B
|
||
|
WMF_SPECTRUM_ANAYZER = 0xA10C
|
||
|
GSM_610 = 0xA10D
|
||
|
GSM_620 = 0xA10E
|
||
|
GSM_660 = 0xA10F
|
||
|
GSM_690 = 0xA110
|
||
|
GSM_ADAPTIVE_MULTIRATE_WB = 0xA111
|
||
|
POLYCOM_G722 = 0xA112
|
||
|
POLYCOM_G728 = 0xA113
|
||
|
POLYCOM_G729_A = 0xA114
|
||
|
POLYCOM_SIREN = 0xA115
|
||
|
GLOBAL_IP_ILBC = 0xA116
|
||
|
RADIOTIME_TIME_SHIFT_RADIO = 0xA117
|
||
|
NICE_ACA = 0xA118
|
||
|
NICE_ADPCM = 0xA119
|
||
|
VOCORD_G721 = 0xA11A
|
||
|
VOCORD_G726 = 0xA11B
|
||
|
VOCORD_G722_1 = 0xA11C
|
||
|
VOCORD_G728 = 0xA11D
|
||
|
VOCORD_G729 = 0xA11E
|
||
|
VOCORD_G729_A = 0xA11F
|
||
|
VOCORD_G723_1 = 0xA120
|
||
|
VOCORD_LBC = 0xA121
|
||
|
NICE_G728 = 0xA122
|
||
|
FRACE_TELECOM_G729 = 0xA123
|
||
|
CODIAN = 0xA124
|
||
|
FLAC = 0xF1AC
|
||
|
EXTENSIBLE = 0xFFFE
|
||
|
DEVELOPMENT = 0xFFFF
|
||
|
|
||
|
|
||
|
KNOWN_WAVE_FORMATS = {WAVE_FORMAT.PCM, WAVE_FORMAT.IEEE_FLOAT}
|
||
|
|
||
|
# assumes file pointer is immediately
|
||
|
# after the 'fmt ' id
|
||
|
|
||
|
|
||
|
def _read_fmt_chunk(fid, is_big_endian):
|
||
|
"""
|
||
|
Returns
|
||
|
-------
|
||
|
size : int
|
||
|
size of format subchunk in bytes (minus 8 for "fmt " and itself)
|
||
|
format_tag : int
|
||
|
PCM, float, or compressed format
|
||
|
channels : int
|
||
|
number of channels
|
||
|
fs : int
|
||
|
sampling frequency in samples per second
|
||
|
bytes_per_second : int
|
||
|
overall byte rate for the file
|
||
|
block_align : int
|
||
|
bytes per sample, including all channels
|
||
|
bit_depth : int
|
||
|
bits per sample
|
||
|
"""
|
||
|
if is_big_endian:
|
||
|
fmt = '>'
|
||
|
else:
|
||
|
fmt = '<'
|
||
|
|
||
|
size = res = struct.unpack(fmt+'I', fid.read(4))[0]
|
||
|
bytes_read = 0
|
||
|
|
||
|
if size < 16:
|
||
|
raise ValueError("Binary structure of wave file is not compliant")
|
||
|
|
||
|
res = struct.unpack(fmt+'HHIIHH', fid.read(16))
|
||
|
bytes_read += 16
|
||
|
|
||
|
format_tag, channels, fs, bytes_per_second, block_align, bit_depth = res
|
||
|
|
||
|
if format_tag == WAVE_FORMAT.EXTENSIBLE and size >= (16+2):
|
||
|
ext_chunk_size = struct.unpack(fmt+'H', fid.read(2))[0]
|
||
|
bytes_read += 2
|
||
|
if ext_chunk_size >= 22:
|
||
|
extensible_chunk_data = fid.read(22)
|
||
|
bytes_read += 22
|
||
|
raw_guid = extensible_chunk_data[2+4:2+4+16]
|
||
|
# GUID template {XXXXXXXX-0000-0010-8000-00AA00389B71} (RFC-2361)
|
||
|
# MS GUID byte order: first three groups are native byte order,
|
||
|
# rest is Big Endian
|
||
|
if is_big_endian:
|
||
|
tail = b'\x00\x00\x00\x10\x80\x00\x00\xAA\x00\x38\x9B\x71'
|
||
|
else:
|
||
|
tail = b'\x00\x00\x10\x00\x80\x00\x00\xAA\x00\x38\x9B\x71'
|
||
|
if raw_guid.endswith(tail):
|
||
|
format_tag = struct.unpack(fmt+'I', raw_guid[:4])[0]
|
||
|
else:
|
||
|
raise ValueError("Binary structure of wave file is not compliant")
|
||
|
|
||
|
if format_tag not in KNOWN_WAVE_FORMATS:
|
||
|
try:
|
||
|
format_name = WAVE_FORMAT(format_tag).name
|
||
|
except ValueError:
|
||
|
format_name = f'{format_tag:#06x}'
|
||
|
raise ValueError(f"Unknown wave file format: {format_name}. Supported "
|
||
|
"formats: " +
|
||
|
', '.join(x.name for x in KNOWN_WAVE_FORMATS))
|
||
|
|
||
|
# move file pointer to next chunk
|
||
|
if size > (bytes_read):
|
||
|
fid.read(size - bytes_read)
|
||
|
|
||
|
return (size, format_tag, channels, fs, bytes_per_second, block_align,
|
||
|
bit_depth)
|
||
|
|
||
|
|
||
|
# assumes file pointer is immediately after the 'data' id
|
||
|
def _read_data_chunk(fid, format_tag, channels, bit_depth, is_big_endian,
|
||
|
mmap=False):
|
||
|
if is_big_endian:
|
||
|
fmt = '>I'
|
||
|
else:
|
||
|
fmt = '<I'
|
||
|
|
||
|
# Size of the data subchunk in bytes
|
||
|
size = struct.unpack(fmt, fid.read(4))[0]
|
||
|
|
||
|
# Number of bytes per sample
|
||
|
bytes_per_sample = bit_depth//8
|
||
|
if bit_depth == 8:
|
||
|
dtype = 'u1'
|
||
|
else:
|
||
|
if is_big_endian:
|
||
|
dtype = '>'
|
||
|
else:
|
||
|
dtype = '<'
|
||
|
if format_tag == WAVE_FORMAT.PCM:
|
||
|
dtype += 'i%d' % bytes_per_sample
|
||
|
else:
|
||
|
dtype += 'f%d' % bytes_per_sample
|
||
|
if not mmap:
|
||
|
data = numpy.frombuffer(fid.read(size), dtype=dtype)
|
||
|
else:
|
||
|
start = fid.tell()
|
||
|
data = numpy.memmap(fid, dtype=dtype, mode='c', offset=start,
|
||
|
shape=(size//bytes_per_sample,))
|
||
|
fid.seek(start + size)
|
||
|
|
||
|
if channels > 1:
|
||
|
data = data.reshape(-1, channels)
|
||
|
return data
|
||
|
|
||
|
|
||
|
def _skip_unknown_chunk(fid, is_big_endian):
|
||
|
if is_big_endian:
|
||
|
fmt = '>I'
|
||
|
else:
|
||
|
fmt = '<I'
|
||
|
|
||
|
data = fid.read(4)
|
||
|
# call unpack() and seek() only if we have really read data from file
|
||
|
# otherwise empty read at the end of the file would trigger
|
||
|
# unnecessary exception at unpack() call
|
||
|
# in case data equals somehow to 0, there is no need for seek() anyway
|
||
|
if data:
|
||
|
size = struct.unpack(fmt, data)[0]
|
||
|
fid.seek(size, 1)
|
||
|
|
||
|
|
||
|
def _read_riff_chunk(fid):
|
||
|
str1 = fid.read(4) # File signature
|
||
|
if str1 == b'RIFF':
|
||
|
is_big_endian = False
|
||
|
fmt = '<I'
|
||
|
elif str1 == b'RIFX':
|
||
|
is_big_endian = True
|
||
|
fmt = '>I'
|
||
|
else:
|
||
|
# There are also .wav files with "FFIR" or "XFIR" signatures?
|
||
|
raise ValueError(f"File format {repr(str1)} not understood. Only "
|
||
|
"'RIFF' and 'RIFX' supported.")
|
||
|
|
||
|
# Size of entire file
|
||
|
file_size = struct.unpack(fmt, fid.read(4))[0] + 8
|
||
|
|
||
|
str2 = fid.read(4)
|
||
|
if str2 != b'WAVE':
|
||
|
raise ValueError(f"Not a WAV file. RIFF form type is {repr(str2)}.")
|
||
|
|
||
|
return file_size, is_big_endian
|
||
|
|
||
|
|
||
|
def read(filename, mmap=False):
|
||
|
"""
|
||
|
Open a WAV file
|
||
|
|
||
|
Return the sample rate (in samples/sec) and data from a WAV file.
|
||
|
|
||
|
Parameters
|
||
|
----------
|
||
|
filename : string or open file handle
|
||
|
Input wav file.
|
||
|
mmap : bool, optional
|
||
|
Whether to read data as memory-mapped.
|
||
|
Only to be used on real files (Default: False).
|
||
|
|
||
|
.. versionadded:: 0.12.0
|
||
|
|
||
|
Returns
|
||
|
-------
|
||
|
rate : int
|
||
|
Sample rate of wav file.
|
||
|
data : numpy array
|
||
|
Data read from wav file. Data-type is determined from the file;
|
||
|
see Notes.
|
||
|
|
||
|
Notes
|
||
|
-----
|
||
|
This function cannot read wav files with 24-bit data.
|
||
|
|
||
|
Common data types: [1]_
|
||
|
|
||
|
===================== =========== =========== =============
|
||
|
WAV format Min Max NumPy dtype
|
||
|
===================== =========== =========== =============
|
||
|
32-bit floating-point -1.0 +1.0 float32
|
||
|
32-bit PCM -2147483648 +2147483647 int32
|
||
|
16-bit PCM -32768 +32767 int16
|
||
|
8-bit PCM 0 255 uint8
|
||
|
===================== =========== =========== =============
|
||
|
|
||
|
Note that 8-bit PCM is unsigned.
|
||
|
|
||
|
References
|
||
|
----------
|
||
|
.. [1] IBM Corporation and Microsoft Corporation, "Multimedia Programming
|
||
|
Interface and Data Specifications 1.0", section "Data Format of the
|
||
|
Samples", August 1991
|
||
|
http://www.tactilemedia.com/info/MCI_Control_Info.html
|
||
|
|
||
|
Examples
|
||
|
--------
|
||
|
>>> from os.path import dirname, join as pjoin
|
||
|
>>> from scipy.io import wavfile
|
||
|
>>> import scipy.io
|
||
|
|
||
|
Get the filename for an example .wav file from the tests/data directory.
|
||
|
|
||
|
>>> data_dir = pjoin(dirname(scipy.io.__file__), 'tests', 'data')
|
||
|
>>> wav_fname = pjoin(data_dir, 'test-44100Hz-2ch-32bit-float-be.wav')
|
||
|
|
||
|
Load the .wav file contents.
|
||
|
|
||
|
>>> samplerate, data = wavfile.read(wav_fname)
|
||
|
>>> print(f"number of channels = {data.shape[1]}")
|
||
|
number of channels = 2
|
||
|
>>> length = data.shape[0] / samplerate
|
||
|
>>> print(f"length = {length}s")
|
||
|
length = 0.01s
|
||
|
|
||
|
Plot the waveform.
|
||
|
|
||
|
>>> import matplotlib.pyplot as plt
|
||
|
>>> import numpy as np
|
||
|
>>> time = np.linspace(0., length, data.shape[0])
|
||
|
>>> plt.plot(time, data[:, 0], label="Left channel")
|
||
|
>>> plt.plot(time, data[:, 1], label="Right channel")
|
||
|
>>> plt.legend()
|
||
|
>>> plt.xlabel("Time [s]")
|
||
|
>>> plt.ylabel("Amplitude")
|
||
|
>>> plt.show()
|
||
|
|
||
|
"""
|
||
|
if hasattr(filename, 'read'):
|
||
|
fid = filename
|
||
|
mmap = False
|
||
|
else:
|
||
|
fid = open(filename, 'rb')
|
||
|
|
||
|
try:
|
||
|
file_size, is_big_endian = _read_riff_chunk(fid)
|
||
|
fmt_chunk_received = False
|
||
|
data_chunk_received = False
|
||
|
channels = 1
|
||
|
bit_depth = 8
|
||
|
format_tag = WAVE_FORMAT.PCM
|
||
|
while fid.tell() < file_size:
|
||
|
# read the next chunk
|
||
|
chunk_id = fid.read(4)
|
||
|
|
||
|
if not chunk_id:
|
||
|
if data_chunk_received:
|
||
|
# End of file but data successfully read
|
||
|
warnings.warn(
|
||
|
"Reached EOF prematurely; finished at {:d} bytes, "
|
||
|
"expected {:d} bytes from header."
|
||
|
.format(fid.tell(), file_size),
|
||
|
WavFileWarning, stacklevel=2)
|
||
|
break
|
||
|
else:
|
||
|
raise ValueError("Unexpected end of file.")
|
||
|
elif len(chunk_id) < 4:
|
||
|
msg = f"Incomplete chunk ID: {repr(chunk_id)}"
|
||
|
# If we have the data, ignore the broken chunk
|
||
|
if fmt_chunk_received and data_chunk_received:
|
||
|
warnings.warn(msg + ", ignoring it.", WavFileWarning,
|
||
|
stacklevel=2)
|
||
|
else:
|
||
|
raise ValueError(msg)
|
||
|
|
||
|
if chunk_id == b'fmt ':
|
||
|
fmt_chunk_received = True
|
||
|
fmt_chunk = _read_fmt_chunk(fid, is_big_endian)
|
||
|
format_tag, channels, fs = fmt_chunk[1:4]
|
||
|
bit_depth = fmt_chunk[6]
|
||
|
if bit_depth not in {8, 16, 32, 64, 96, 128}:
|
||
|
raise ValueError("Unsupported bit depth: the wav file "
|
||
|
"has {}-bit data.".format(bit_depth))
|
||
|
elif chunk_id == b'fact':
|
||
|
_skip_unknown_chunk(fid, is_big_endian)
|
||
|
elif chunk_id == b'data':
|
||
|
data_chunk_received = True
|
||
|
if not fmt_chunk_received:
|
||
|
raise ValueError("No fmt chunk before data")
|
||
|
data = _read_data_chunk(fid, format_tag, channels, bit_depth,
|
||
|
is_big_endian, mmap)
|
||
|
elif chunk_id == b'LIST':
|
||
|
# Someday this could be handled properly but for now skip it
|
||
|
_skip_unknown_chunk(fid, is_big_endian)
|
||
|
elif chunk_id in {b'JUNK', b'Fake'}:
|
||
|
# Skip alignment chunks without warning
|
||
|
_skip_unknown_chunk(fid, is_big_endian)
|
||
|
else:
|
||
|
warnings.warn("Chunk (non-data) not understood, skipping it.",
|
||
|
WavFileWarning, stacklevel=2)
|
||
|
_skip_unknown_chunk(fid, is_big_endian)
|
||
|
finally:
|
||
|
if not hasattr(filename, 'read'):
|
||
|
fid.close()
|
||
|
else:
|
||
|
fid.seek(0)
|
||
|
|
||
|
return fs, data
|
||
|
|
||
|
|
||
|
def write(filename, rate, data):
|
||
|
"""
|
||
|
Write a NumPy array as a WAV file.
|
||
|
|
||
|
Parameters
|
||
|
----------
|
||
|
filename : string or open file handle
|
||
|
Output wav file.
|
||
|
rate : int
|
||
|
The sample rate (in samples/sec).
|
||
|
data : ndarray
|
||
|
A 1-D or 2-D NumPy array of either integer or float data-type.
|
||
|
|
||
|
Notes
|
||
|
-----
|
||
|
* Writes a simple uncompressed WAV file.
|
||
|
* To write multiple-channels, use a 2-D array of shape
|
||
|
(Nsamples, Nchannels).
|
||
|
* The bits-per-sample and PCM/float will be determined by the data-type.
|
||
|
|
||
|
Common data types: [1]_
|
||
|
|
||
|
===================== =========== =========== =============
|
||
|
WAV format Min Max NumPy dtype
|
||
|
===================== =========== =========== =============
|
||
|
32-bit floating-point -1.0 +1.0 float32
|
||
|
32-bit PCM -2147483648 +2147483647 int32
|
||
|
16-bit PCM -32768 +32767 int16
|
||
|
8-bit PCM 0 255 uint8
|
||
|
===================== =========== =========== =============
|
||
|
|
||
|
Note that 8-bit PCM is unsigned.
|
||
|
|
||
|
References
|
||
|
----------
|
||
|
.. [1] IBM Corporation and Microsoft Corporation, "Multimedia Programming
|
||
|
Interface and Data Specifications 1.0", section "Data Format of the
|
||
|
Samples", August 1991
|
||
|
http://www.tactilemedia.com/info/MCI_Control_Info.html
|
||
|
|
||
|
Examples
|
||
|
--------
|
||
|
Create a 100Hz sine wave, sampled at 44100Hz.
|
||
|
Write to 16-bit PCM, Mono.
|
||
|
|
||
|
>>> from scipy.io.wavfile import write
|
||
|
>>> samplerate = 44100; fs = 100
|
||
|
>>> t = np.linspace(0., 1., samplerate)
|
||
|
>>> amplitude = np.iinfo(np.int16).max
|
||
|
>>> data = amplitude * np.sin(2. * np.pi * fs * t)
|
||
|
>>> write("example.wav", samplerate, data)
|
||
|
|
||
|
"""
|
||
|
if hasattr(filename, 'write'):
|
||
|
fid = filename
|
||
|
else:
|
||
|
fid = open(filename, 'wb')
|
||
|
|
||
|
fs = rate
|
||
|
|
||
|
try:
|
||
|
dkind = data.dtype.kind
|
||
|
if not (dkind == 'i' or dkind == 'f' or (dkind == 'u' and
|
||
|
data.dtype.itemsize == 1)):
|
||
|
raise ValueError("Unsupported data type '%s'" % data.dtype)
|
||
|
|
||
|
header_data = b''
|
||
|
|
||
|
header_data += b'RIFF'
|
||
|
header_data += b'\x00\x00\x00\x00'
|
||
|
header_data += b'WAVE'
|
||
|
|
||
|
# fmt chunk
|
||
|
header_data += b'fmt '
|
||
|
if dkind == 'f':
|
||
|
format_tag = WAVE_FORMAT.IEEE_FLOAT
|
||
|
else:
|
||
|
format_tag = WAVE_FORMAT.PCM
|
||
|
if data.ndim == 1:
|
||
|
channels = 1
|
||
|
else:
|
||
|
channels = data.shape[1]
|
||
|
bit_depth = data.dtype.itemsize * 8
|
||
|
bytes_per_second = fs*(bit_depth // 8)*channels
|
||
|
block_align = channels * (bit_depth // 8)
|
||
|
|
||
|
fmt_chunk_data = struct.pack('<HHIIHH', format_tag, channels, fs,
|
||
|
bytes_per_second, block_align, bit_depth)
|
||
|
if not (dkind == 'i' or dkind == 'u'):
|
||
|
# add cbSize field for non-PCM files
|
||
|
fmt_chunk_data += b'\x00\x00'
|
||
|
|
||
|
header_data += struct.pack('<I', len(fmt_chunk_data))
|
||
|
header_data += fmt_chunk_data
|
||
|
|
||
|
# fact chunk (non-PCM files)
|
||
|
if not (dkind == 'i' or dkind == 'u'):
|
||
|
header_data += b'fact'
|
||
|
header_data += struct.pack('<II', 4, data.shape[0])
|
||
|
|
||
|
# check data size (needs to be immediately before the data chunk)
|
||
|
if ((len(header_data)-4-4) + (4+4+data.nbytes)) > 0xFFFFFFFF:
|
||
|
raise ValueError("Data exceeds wave file size limit")
|
||
|
|
||
|
fid.write(header_data)
|
||
|
|
||
|
# data chunk
|
||
|
fid.write(b'data')
|
||
|
fid.write(struct.pack('<I', data.nbytes))
|
||
|
if data.dtype.byteorder == '>' or (data.dtype.byteorder == '=' and
|
||
|
sys.byteorder == 'big'):
|
||
|
data = data.byteswap()
|
||
|
_array_tofile(fid, data)
|
||
|
|
||
|
# Determine file size and place it in correct
|
||
|
# position at start of the file.
|
||
|
size = fid.tell()
|
||
|
fid.seek(4)
|
||
|
fid.write(struct.pack('<I', size-8))
|
||
|
|
||
|
finally:
|
||
|
if not hasattr(filename, 'write'):
|
||
|
fid.close()
|
||
|
else:
|
||
|
fid.seek(0)
|
||
|
|
||
|
|
||
|
def _array_tofile(fid, data):
|
||
|
# ravel gives a c-contiguous buffer
|
||
|
fid.write(data.ravel().view('b').data)
|