Processing files in specific order

Question

I have 40k images in a folder. The file names follow the following pattern:

1558058263_18ea873ddcf8c65e.jpg
1558408930_63c29ce4462ec194.jpg 
1558062887_18ea873ddcf8c65e.jpg

In this the first part of the file name is the time stamp and the second part is the machine id that generated the image.

I want to process each of these files in a sequential order based on only the time stamp. How can I take the files sequentially for processing. I am using python3 for selecting the files. The current code is as follows:

 for root, dirs, files in os.walk(path):
                for name in files:
                        img=fr.load_image_file('/home/ubuntu/faces/' + name)

Answer 1

It seems to me that you could use the sort() or sorted() functions (from Stack Overflow):

# ...
for root, dirs, files in os.walk(path):
   files.sort()
   for name in files:
      print(name)

or

# ...
for root, dirs, files in os.walk(path):
   for name in sorted(files):
      print(name)

Answer 2

You might try sorting via a lambda (UNTESTED):

for root, dirs, files in os.walk(path):
    for name in sorted(files,  key=lambda x: int(re.search(r'\d+', x).group())):
        img=fr.load_image_file('/home/ubuntu/faces/' + name)

Answer 3

The sort command should give you what you want.

ls | sort -n -t '_' -k1

-n sorts numerically, instead of the default lexicographically.
-t '_' specifies _ as a field separator.
-k1 sorts on the first field.

Answer 4

Tested and it worked fine

find . -type f -iname "*.jpg" 2>/dev/null| sed "s/\.\///g"| awk -F "_" '{print $1,$2}'| sort -k1| awk 'OFS="_" {print $1,$2}'

Will update with Python script asap