c 语言写的字符串编码识别库，更快更准确
# coding=utf-8
import cchardet
source = u'你好，世界'
utf8_source = source.encode('utf-8')
gbk_source = source.encode('gbk')
print cchardet.detect(utf8_source)
print cchardet.detect(gbk_source)
print utf8_source.decode(cchardet.detect(utf8_source)['encoding'])
print utf8_source.decode(cchardet.detect(gbk_source)['encoding'])