python分割8KHz16Bit44Header的Wave文件
#encoding=GBK
import os
import sys
import string
from struct import pack, unpack
'''
[52 49 46 46] [char ] [4bytes]'RIFF' –RIFF file identification
[E4 6C 00 00] [int ] [4bytes]<length> –File length field
[57 41 56 45] [char ] [4bytes]'WAVE' –WAVE chunk identification
[66 6D 74 20] [char ] [4bytes]'fmt' –format sub-chunk identification
[10 00 00 00] [int ] [4bytes]flength –length of format sub-chunk
[01 00] [short] [2bytes]format –format specifier
[01 00] [short] [2bytes]chans –number of channels
[40 1F 00 00] [int ] [4bytes]sampsRate –sample rate in Hz
[80 3E 00 00] [int ] [4bytes]bpsec –bytes per second
[02 00] [short] [2bytes]bpsample –bytes per sample
[10 00] [short] [2bytes]bpchan –bits per channel
[64 61 74 61] [char ] [4bytes]'data' –data sub-chunk identification
[C0 6C 00 00] [int ] [4bytes]dlength –length of data sub-chuk
#30 00 00 00 -- 00 00 00 30 -- 0 * 16^0 + 3 * 16^1 = 48
#40 1F 00 00 -- 00 00 1F 40 -- 0 * 16^0 + 4 * 16^1 + 15 * 16^2 + 1 * 16^3 = 8000
wavheader = '4si4s4sihhiihh4si'
https://docs.python.org/release/2.6.6/library/struct.html?highlight=pack#struct.pack
'''
class normalWave():
headerIde = '4si4s4sihhiihh4si'
wavename = ""
waveobj = ""
wavelen = 0
def __init__(self, wavename):
self.wavename = wavename
self.waveobj = open(self.wavename,"rb")
def getheaderinfo(self):
self.waveobj.seek(0)
sequ = list(unpack(self.headerIde, self.waveobj.read(44)))
self.wavelen = round(sequ[-1] * 1.0 / sequ[-6] / 2.0, 8)
return sequ
def getchildwave(self, headerdata, name, cutstime, cutetime, expandTime):
expandTime = expandTime / 1000.0
if cutstime > 0:
cutstime = cutstime - expandTime if cutstime - expandTime >= 0 else cutstime
if cutetime <= 0 or cutetime <= cutstime:
return
else:
cutetime = cutetime + expandTime if cutetime + expandTime <= self.wavelen else cutetime
dataLen = (int)(round((cutetime - cutstime) * 8000 * 2, 8))
sBytes = (int)(round(cutstime * 8000 * 2, 8)) + 44
if sBytes % 2 != 0:
sBytes += 1
if dataLen % 2 != 0:
dataLen -= 1
#print cutstime,cutetime, self.wavelen, sBytes - 44,sBytes, dataLen
if dataLen <= 0: return
headerdata[1] = dataLen + 36
headerdata[-1] = dataLen
child = open(name,"w")
child.write(pack(self.headerIde, *headerdata))
self.waveobj.seek(sBytes)
child.write(self.waveobj.read(dataLen))
child.close()
def close(self):
self.waveobj.close()
def cutwavbyInfo(wavename, cutinfolist, expandTime, dir):
for line in cutinfolist:
childname = ""
stime = 0.0
etime = 0.0
childArr = line.strip().split("\t")
if len(childArr) < 2:continue
childname = dir + "/" + childArr[0]
timeArr = childArr[1].replace("[","").replace("]","").split(",")
if len(timeArr) < 2:continue
stime = string.atof(timeArr[0])
etime = string.atof(timeArr[1])
wave = normalWave(wavename)
header = wave.getheaderinfo()
wave.getchildwave(header, childname, stime, etime, expandTime)
wave.close()
def readCutInfoFile(file, dir, expandTime):
os.system("rm -rf " + dir + "; mkdir " + dir)
fileObj = open(file,"r")
index = 0
wavpath = ""
childlist = []
for line in fileObj:
line = line.strip()
if line == ".":
cutwavbyInfo(wavpath, childlist, expandTime, dir)
index = 0
wavpath = ""
childlist = []
else:
index += 1
if index == 1:
wavpath = line
else:
childlist.append(line)
if len(wavpath) > 0 and len(childlist) > 0:
cutwavbyInfo(wavpath, childlist, expandTime, dir)
if __name__ == '__main__':
if len(sys.argv) != 4:
print "Usage cutInfoFile[in] cutWavDir[in] expandTime[in]"
print " cutInfoFile: x_1.wav\t[0,2.23]"
print " expandTime : 50/100/200(ms)"
sys.exit(-1)
readCutInfoFile(sys.argv[1],sys.argv[2],string.atoi(sys.argv[3]))
