Python修改MP3文件的方法

本文实例讲述了Python修改MP3文件的方法。分享给大家供大家参考。具体如下：

用这个程序修改后的MP3比原来要小一些了，因为一张图片被删除了，起到了给MP3"瘦身"的作用。在一些mp3中，每个都有一张400多K的图片，10几个MP3，就相当一个普通MP3文件的大小了。

# -*- coding: cp936 -*-

"""

将MP3文件中的ID3V2.3部分去掉,以便在MP3机上播放

用法：mp3lcear [源mp3目录] [生成的mp3目录]

"""

import sys

import os

import string

import shutil

import struct

import thread

import threading

import time

mp3suffix = 'mp3'

class Process(threading.Thread):

"""

简单地在运行的过程中显示进度

"""

def __init__(self,msg,sleepTime):

threading.Thread.__init__(self)

self.msg = msg

self.running = True

self.sleepTime = sleepTime

def setPause(self,pause):

self.pause = pause

def setRunning(self,running):

self.running = running

def run (self):

while(self.running):

self.pause.wait()

print self.msg,

time.sleep(self.sleepTime)

def usage(code, msg=''):

"""

程序的使用方法

"""

print >> sys.stderr, __doc__

if msg:

print >> sys.stderr, msg

sys.exit(code)

def checkDir(argDir,create=False):

"""

检查目录是否存在,如果create为Ture,则新建一个目录

"""

tempDir = None

if(not os.path.isdir(argDir)):

currentDir = os.path.abspath(os.curdir)

tempDir = os.path.join(currentDir,argDir)

if(not os.path.isdir(tempDir) and create):

os.mkdir(tempDir)

else:

usage(1,"目录"+argDir+"不存在")

else:

tempDir = os.path.abspath(argDir)

return tempDir

def clearMp3(srcFile,destFile):

"""

修改mp3文件，并将其创建到destFile所指定的地址

"""

global process

srcfp = None

filesize = os.path.getsize(srcFile)

try:

srcfp = open(srcFile,'rb')

head = srcfp.read(3)

if(head=='ID3'):

srcfp.seek(3,1)

size = srcfp.read(4)

if(not len(size)==4):

print srcFile+'文件格式错误'

else:

size0 = struct.unpack('b',size[0])[0]

size1 = struct.unpack('b',size[1])[0]

size2 = struct.unpack('b',size[2])[0]

size3 = struct.unpack('b',size[3])[0]

headSize =(((size0&0x7f)<<21) | ((size1&0x7f)<<14) | ((size2&0x7f)<<7) | (size3&0x7f))

filesize = filesize - headSize

destfp = None

try:

dataLen = 0

destfp = open(destFile,'wb')

srcfp.seek(headSize,1)

data=srcfp.read(1024)

while (data!= ''):

destfp.write(data)

data=srcfp.read(1024)

except Exception,e:

print '创建文件'+destFile+'错误',e

try:

if (destfp != None):

destfp.close

except Exception,de:

print de

else:

print srcFile+'不需要修改 拷贝',

try:

shutil.copyfile(srcFile,destFile)

except Exception, ce:

print ce

except Exception,oe:

print '修改中出错',oe

try:

if (srcfp != None):

srcfp.close()

except Exception,se:

print de

if __name__ == "__main__":

if(len(sys.argv)<3):

usage(1)

global process

sourceDir = checkDir(sys.argv[1])

destDir = checkDir(sys.argv[2],True)

print 'Mp3源目录',sourceDir

print 'Mp3目的目录',destDir

process = Process('...',1)

pause = threading.Event()

process.setPause(pause)

process.start()

for filename in os.listdir(sourceDir):

srcPath = os.path.join(sourceDir, filename)

destPath = os.path.join(destDir, filename)

if os.path.isfile(srcPath):

print '开始处理 '+filename,

tempfilename = filename.lower()

if(not tempfilename.endswith(mp3suffix)):

print filename+'不是一个mp3文件n'

else:

pause.set()

clearMp3(srcPath,destPath)

pause.clear()

print '结束 n'

pause.set()

process.running = False

sys.exit(0)

希望本文所述对大家的Python程序设计有所帮助。