Change name of files in a directory: Python

Question

I have .wav files in the directory "dataset"

import os
dataset_path = 'C:/dataset'

def change_filenames(dataset_path):

    i = 0  # target filename
    for old_name in os.listdir(dataset_path):
        os.rename(old_name, str(i) + '.wav')
        i+=1    

change_filenames(dataset_path)

Error: FileNotFoundError: [WinError 2] The system cannot find the file specified: 'sound1.wav' -> '0.wav'

What is the error mean? The file is in the directory and is reachable by the code, why not system?

Answer 1

As Zerodf points out, the problem is likely that your current working directory is not the same as the dataset_path directory you specified. So when os.rename goes to rename sound1.wav, it looks for it in your current working directory (which might not be the same as dataset_path), can't find it, and throws that error.

Since your dataset_path variable contains an absolute path, you can make sure that everything that os.rename tries to rename is an absolute path by tacking each filename onto dataset_path using os.path.join(). That is, change

os.rename(old_name, str(i) + '.wav')

to

os.rename(os.path.join(dataset_path, old_name), os.path.join(dataset_path, str(i) + '.wav'))

Then when os.rename goes to rename sound1.wav, it will look for C:/dataset/sound1.wav, which it should find without a problem.

Also note that you can see what your current working directory is with the getcwd() function in os.

import os

print(os.getcwd())