Preserving all the subdirectories when saving a file

I have a folder with various subdirectories and within those are files with different extensions such as .jpg, .png, etc. I would like to only extract the .jpg files and perform some work on them such as cropping, etc and then I want to save these new files (i.e. cropped ones) into the subdirectories that they came from. However, I don't want these new files saved into the same folder from which they came from. Instead, I want them saved into a different folder that contains all of the same subdirectories with the same names from which they came from. This new folder must only contain the new cropped files. I have included an illustration below to better explain my question.

I have tried the following:

for imgs in glob.iglob(self.Main_Folder   '//**/*.jpg', recursive=True):
    Output_Folder = os.path.join(os.path.dirname(imgs), "cropped"   str(idx)   ".jpg")

However, this overwrites the .jpg files located in their subdirectories in the Main Folder (i.e. it overwrites 1.jpg, 2.jpg, etc). Any help on this would be much appreciated!

CodePudding user response：

One thing to realize is that the paths that glob.iglob generates include the entire matched pattern, which includes your self.Main_Folder. So, you must first determine the sub-path relative to the main folder, and join that with the output folder. E.g. "main_folder/found/path.jpg" -> "found/path.jpg" -> "output_folder/found/path.jpg". The pathlib library provides an easy way to do that with Path.relative_to.

import glob
import os
import pathlib

main_folder = "somewhere/Main Folder"
output_folder = "somewhere/Output Folder"
for name in glob.iglob(os.path.join(main_folder, "**/*")):
    path = pathlib.Path(name)
    sub_path = path.relative_to(main_folder)
    output_path = os.path.join(output_folder, sub_path)
    print(output_path)

You can get fancier by using more of the pathlib API (especially the ability to join paths with /), but whether this is more clear is probably debatable:

main_folder = "somewhere/Main Folder"
output_folder = "somewhere/Output Folder"
for name in glob.iglob(str(main_folder / "**/*")):
    path = pathlib.Path(name)
    output_path = output_folder / path.relative_to(main_folder)
    print(output_path)

In Python 3.10, which as of this writing is the newest Python version, this can be simpler:

main_folder = pathlib.Path("scratch")
output_folder = pathlib.Path("output")
for name in glob.iglob("**/*", root_dir=main_folder):
    output_path = output_folder / name
    print(output_path)

CodePudding user response：

Basically, these are 3 issues

iglob for finding jpg files
Pillow for image manipulation
a mechanism for creating path to new jpg file

First you got already, second is trivial, third like this:

from pathlib import Path
apath = Path(“a/b/c/a.jpg”)  # to your jpg
root = “a/b”
new_dir = Path(“some/path”)
new_path = new_dir.joinpath(apath.relative_to(root))
# should be some/path/c/a.jpg

No python here, so not tested.