Python Script I am working on

evil · 2010-06-08 23:07:30

Hi all. I have been reading about the Python language and this is my first script. It's a batch renaming script that adds 0's to the count so that the filenames stay in order. I was hoping that perhaps I could pick your minds on a better way to do this. I have it pre-programmed up to 999 (001, 010, 100, etc). I was wondering if there is a way to see how many photos there are in the directory, and say if there is 1000, automatically use 4 digits from 1-1000.. for example 0001.jpg, 0010.jpg, 0100.jpg, 1000.jpg. If there is only 90, then up to 10 use 01.jpg, 02.jpg, etc. I hope I am explaining this properly.. anyways, here is the script so far:

EDIT: Updated script with new code. Now the script will add the corresponding number of zero's depending on the # of specified files and the starting count.

EDIT2: Btw, I know with the following code I don't need to use the global statement with the variables, however that is how the script started because of the original structure. From what I have read, if a variable isn't defined global it wont be accessible within a function (def)? I may have misread or perhaps I am confusing function with class. Anyway, I didn't think it would hurt to keep it that way for this particular script.

EDIT3: Using N30N's advice, I used the str.endswith string manipulator and implemented optparse library. Hats off to you N30N!! I was looking for something like optparse without having to handle everything on the scripts end.

EDIT4: Got rid of the global line and condensed ren_filecount variable prior to looping through the list.

#!/usr/bin/python

import os, sys
from optparse import OptionParser

parser = OptionParser()

parser.add_option("-f", "--filetype", metavar="filetype",default=".jpg", help="Choose file type to rename", type="string", dest="ren_filetype")
parser.add_option("-p", "--prefix", metavar="prefix", default="Pictures", help="Choose a filename prefix", type="string", dest="ren_prefix")
parser.add_option("-s", "--startcount", metavar="startcount", default=1, help="Choose what number to start counting from", type="int", dest="ren_startcount")
parser.add_option("-d", "--directory", metavar="directory", default=".", help="Define a different directory besides the working directory", type="string", dest="ren_directory")

(options, args) = parser.parse_args()

ren_filetype = options.ren_filetype
ren_prefix = options.ren_prefix
ren_startcount = options.ren_startcount
ren_directory = options.ren_directory

ren_list=[]
ren_filecount=0

os.chdir(ren_directory)

for a in os.listdir('.'):
    if a.lower().endswith(ren_filetype) == True:
        ren_filecount=ren_filecount+1
    ren_list.append(a)

ren_filecount='%(#)0' + str(len(str(ren_filecount + ren_startcount))) + 'd'

for b in ren_list:
    os.rename(b, ren_prefix + '-' + (ren_filecount % {"#" : ren_startcount}) + ren_filetype)
    ren_startcount=ren_startcount+1

Last edited by evil (2010-06-12 17:27:16)

ewaller · 2010-06-08 23:19:19

len (os.listdir('.'))

evilgnome · 2010-06-09 00:52:41

check out the standard str methods, like http://docs.python.org/library/stdtypes.html#str.zfill

evil · 2010-06-09 14:20:07

ah, both of those look promising. i'll work on the script when i get home from work. thank you for the advice!

EDIT: I actually somewhat remember reading about zfill. However, it is hard to soak in everything. I am now reading on Classes in the python documentation.

EDIT2: Thank you ewaller and evilgnome for the input. Both came in very handy for the script. I have updated the original post/script above with your suggestions.

Last edited by evil (2010-06-09 20:32:18)

igndenok · 2010-06-09 14:45:06

this is python code that i use for numbering with 0 padding
it's working for me (i think !? if i'm remember correctly for my renaming purpose)

# return file number base on the digit
# that will be use, using zero padding
def file_number(index, digit = 3):
    zero = ""
    index = str(index)
    length = digit - len(index)

    for i in range(length):
        zero += "0"

    zero += index

    return zero

N30N · 2010-06-10 11:24:31

evil wrote:

ren_filetype = sys.argv[1]
ren_prefix = sys.argv[2]
ren_startcount = int(sys.argv[3])
ren_directory = sys.argv[4]

See optparse.

evil wrote:

for a in os.listdir('.'):
    if a[-4:] == ren_filetype:
        ren_filecount=ren_filecount+1

Not all file extensions are the same length, use str.endswith. Also looping through the directory twice is redundant, just store the matching files in a list and use that.

I don't want to talk to you no more, you empty headed animal food trough wiper. I fart in your general direction. Your mother was a hamster and your father smelt of elderberries.

evil · 2010-06-10 11:40:47

N30N:
Awesome! I was actually looking for a much better way to process the arguments. Again, hopefully when I get home from work I'll have some time to start picking at this.

Your definitely right about looping through the list twice. I could speed this up by taking your advice and making a list.

Thanks!!!!

evil · 2010-06-10 17:54:53

N30N: Implemented your suggestions.

Everyone, please let me know what you think and if you see any more improvements that need to be done. Thanks a lot everyone for your help.

Mr.Elendig · 2010-06-10 19:33:00

You can get rid of the "global foo" line, it' does nothing.

edit: more coming

edit2:

Here is some things to think about:

What happens if it doesn't end in ren_filetype?
How will it affect your calculation of the the padding needed?

Last edited by Mr.Elendig (2010-06-10 21:48:32)

tomd123 · 2010-06-10 22:35:49

The way I would do it.

1. Drop optparse and start from scratch
2. list all jpgs in a directory
3. ceil(log10(list of jpgs))
4. start renaming
5 ???
6 PROFIT

evilgnome · 2010-06-10 22:45:09

Making no claims about efficiency or other virtues, this is a way of doing it that makes sense to my brain:

#!/usr/bin/python
import os, sys
import shutil

# Usage: pyrename <file extension> <file prefix> <start count> <directory>
# pyrename jpg Misc 1 .
# pyrename
    
def rename_files(extension='jpg', prefix='Misc-', first_num=1, dir='.'):
    extension = '.' + extension.lower()
    os.chdir(dir)
    file_list = [file for file in os.listdir('.') if file.lower().endswith(extension)]
    num_files = len(file_list)
    highest_num = num_files + first_num - 1
    digits = len(str(highest_num))
    temp_path = 'pyrename-temp'
    os.mkdir(temp_path)
    num = first_num
    for file in file_list:
        new_name = prefix + str(num).zfill(digits) + extension
        shutil.move(file, os.path.join(temp_path, new_name))
        num += 1
    for file in os.listdir(temp_path):
        shutil.move(os.path.join(temp_path, file), dir)
    os.rmdir(temp_path)
    
if __name__ == '__main__':
    try:
        ext, prefix, start, dir = sys.argv[1:]
        rename_files(ext, prefix, int(start), dir)
    except:
        rename_files()

evil · 2010-06-11 10:58:04

tomd123 wrote:

The way I would do it.
1. Drop optparse and start from scratch
2. list all jpgs in a directory
3. ceil(log10(list of jpgs))
4. start renaming
5 ???
6 PROFIT

lol... better watch out for the evil underpants gnomes.

evil · 2010-06-11 21:55:13

The script functions quickly, efficiently and I love using the optparse library. I guess the way to describe it, is that it has that 'command line' feel!?

Anyhow, I tested it by making a directory and then doing something along these lines
touch fakejpeg{1..2000}.jpg
touch fakegif{1..2000}.gif

it ran through 2000 jpgs in less then a second, properly doing everything I wanted.

Thank you all for your help and I always monitor my posts so if anyone does have any thoughts on making this script any more efficient than it is, or perhaps see any potential bugs please post. Since I am learning Python, it would be great to get the experience of making this better and/or fixing bugs.

Thank you all again for taking the time to help me with this!

anrxc · 2010-06-11 23:22:56

file_list = [file for file in os.listdir('.') if file.lower().endswith(extension)]

Consider:

glob.glob(".jpg")

Someone already mentioned zfill, and I'd also like to add enumerate, which is useful in scripts of this kind, consider:

for index, file in enumerate(os.listdir(directory))

Last edited by anrxc (2010-06-11 23:23:50)

evil · 2010-06-12 17:25:51

anrxc:

Thanks for the info on using lower()

Helps out for when pictures have an the same extension with mixed casing.

Arch Linux

#1 2010-06-08 23:07:30

Python Script I am working on

#2 2010-06-08 23:19:19

Re: Python Script I am working on

#3 2010-06-09 00:52:41

Re: Python Script I am working on

#4 2010-06-09 14:20:07

Re: Python Script I am working on

#5 2010-06-09 14:45:06

Re: Python Script I am working on

#6 2010-06-10 11:24:31

Re: Python Script I am working on

#7 2010-06-10 11:40:47

Re: Python Script I am working on

#8 2010-06-10 17:54:53

Re: Python Script I am working on

#9 2010-06-10 19:33:00

Re: Python Script I am working on

#10 2010-06-10 22:35:49

Re: Python Script I am working on

#11 2010-06-10 22:45:09

Re: Python Script I am working on

#12 2010-06-11 10:58:04

Re: Python Script I am working on

#13 2010-06-11 21:55:13

Re: Python Script I am working on

#14 2010-06-11 23:22:56

Re: Python Script I am working on

#15 2010-06-12 17:25:51

Re: Python Script I am working on

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