Question

I am writing a program in PyQT that needs to take messy strings and clean them up. The possible input values are extremely variable. For example I would like to take the strings:

"Seven_Pounds_(BDrip_1080p_ENG-ITA-GER)_Multisub_x264_bluray_.mkv",  
"The_Birds_1963_HDTV_XvidHD_720p-NPW.avi",  
"1892.XVID.AC3.HD.120_min.avi"  

and turn them into:
“Seven Pounds”,
“The Birds”,
“1892”

I have considered using re to escape expressions, but this method seems likely to fail for the last example. The program Media Gerbil uses the google diff-match-patch algorithm to deal with string cleaning. This seems like a better alternative, but I am not sure how to implement it.
Is there another, more effective method for cleaning strings in Python/PyQt, or is the regex or diff-match-patch the best route to follow?

Answer 1

based on your example:

import re

a="The_Birds_1963_HDTV_XvidHD_720p-NPW.avi"
b="Seven_Pounds_(BDrip_1080p_ENG-ITA-GER)_Multisub_x264_bluray_.mkv"
c="1892.XVID.AC3.HD.120_min.avi"

def cleanit(str):
    result = []
    l = re.split('[_.]',str)
    flag = 0
    if re.match('^[a-zA-z]+',l[0]):
        flag = 1
    elif re.match('^[0-9]+',l[0]):
        flag = 2

    if flag == 1:
        for x in l:
            if not re.match('^[a-zA-Z]+',x):
                break;
            result.append(x) 
        return " ".join(result)

    if flag == 2:
        for x in l:
            if not re.match('^[0-9]+',x):
                break;
            result.append(x) 
        return " ".join(result)

if __name__ == '__main__':
    print cleanit(a)
    print cleanit(b)
    print cleanit(c)

will print:

kent$  python cleanit.py
The Birds
Seven Pounds
1892