python分割文件为小文件_一个切割flv文件的python小程序
功能：该工具可以分析flv文件的具体格式，参照 FlvParse.exe 写的，通过改程序加深了对flv的文件格式的理解，及python中对大小端数据的操作
#!/usr/bin/python
from struct import *
from sys import exit
import sys
from os.path import basename
import os
import time
root_path = '/tmp/flv_tag_info/'
def showTagsInfo():
nTag = 0
while True:
TagHeader = f.read(11)
if not TagHeader:
print ">>>>>>>>>>showTagsInfo-End<<<<<<<<<"
nTag += 1
print "\t\t "
tagType = unpack('B',TagHeader[0])
if tagType[0] == 18:
print "\t\t type: ",tagType[0],"(script data)"
elif tagType[0] == 9:
print "\t\t type: ",tagType[0],"(video tag)"
elif tagType[0] == 8:
print "\t\t type: ",tagType[0],"(autio tag)"
else:
print ">>>>>>>>>>>>>showTagsInfo() tagType Error<<<<<<<<<<<<<<
print "\t\t dataSize: ",dataSize[0]
timeStamp = unpack('>I',TagHeader[4:8])
print "\t\t timeStamp:",timeStamp[0]
streamId = unpack('>I','\x00' + TagHeader[8:11])
print "\t\t streamId :",streamId[0]
print "\t\t "
metaTagData = f.read(dataSize[0])
print "\t\t Tag Date len: ",len(metaTagData)
preTagSize = f.read(4)
nPreTagSize = unpack('>I',preTagSize)
print "\t\t nPreTagSize :",nPreTagSize[0]," (",f.tell(),")"
file_path = root_path + basename(f.name)
fout=open(file_path + '/'+ str(int(time.time())) + '.' + str(nTag) + '.tag', 'w')
fout.write(TagHeader + metaTagData + preTagSize)
fout.close()
def showFileHeaderInfo():
flvHeader = f.read(9)
signature = unpack('ccc',flvHeader[0:3])
version = unpack('b',flvHeader[3])
strSignature = ''.join(signature)
if strSignature == 'FLV':
print "Flv structure"
print "\t"
print "\tsignature:",strSignature
print "\tversion: ",version[0]
else:
print ">>>>>>>>>>>>>Not an FlV file<<<<<<<<<<>2
if hasVideo == videoMask:
print "\thasVideo: ",hasVideo
headerSize = unpack('>I',flvHeader[5:9]) ##big-endian(network)
print "\theaderSize:",headerSize[0]
firstTagSize = f.read(4)
file_path = root_path + basename(f.name)
if not os.path.exists(file_path):
os.makedirs(file_path)
fout=open(file_path +'/' + basename(f.name) + '.meta', 'w')
fout.write(flvHeader + firstTagSize)
fout.close()
nFirstTagSize = unpack('>I',firstTagSize)
print "\tfirstTagSize:",nFirstTagSize[0]," (",f.tell(),")"
#main start
if len(sys.argv) < 2:
print "Usage: slice.py [test.flv]"
exit()
f = open(sys.argv[1],'r')
print "Start slice.py Open :",f.name
showFileHeaderInfo()
showTagsInfo()
f.close()