I've performed a recovery for old deleted files! The process was a complete success and recovered files from years ago.
Now the problem is going through all the 400000 files recovered of the type JPG alone.
To deal with this, I've already separated the files by their size and stored the ones that match the criteria on a different directory:
find /path/to/files/ -size +100k -print0 | xargs -0 cp --target-directory=/path/to/filtered/files/
Since the files are to be analyzed remotely, I've prepared a web page to show all files, allowing them to be saved locally. This web page will present the files 20 at a time with navigation arrows!
My question is how to split the 400000 files into sub-directories containing 20 files each, and have the files renamed sequentially:
000001.jpg 000002.jpg ... 000020.jpg
Move into sub-directory, by creating the sub-directory
Repeat until all 400000 have been processed!
page_0002/000021.jpg page_0002/000022.jpg ... page_0002/000040.jpg