The simplest, but easily the most laborious method for renumbering files is to view the directory of files to be renumbered in Windows Explorer, right-click each filename in turn, chose rename and type in the amended number. A slightly faster method is to use Irfanview's Thumbnails feature as described previously. However, the fastest way is to use a computer program like RenumFiles which you can download and which is described below.
The need for re-numbering occurs when a new batch of image files has to be appended to an existing directory of image files. The new numbers need to follow on which means shifting the number of each file in the batch. The basis of the numbering sequence needs to be considered: the options are:-
The program's main window is shown below
This program renumbers (or numbers) a directory-full of JPG files sequentially according to the date which forms part of each file's name. Files with the same date are sequenced within date alphabetically by the original file name. Each file's format is either:-
Unzip the downloaded renum.zip file (see above)to a convenient
directory. The program is called renum.exe. Launch the program
either from Windows Explorer or from the usual
Start | Run dialog box. When the program's window appears, first specify the
directory containing the picture files in the edit box - without the closing "\".
It is very important to note that ALL of the *.JPG files in this directory will be Renamed
but you can cancel the operation after clicking the Renumber button.
Next, enter the desired starting number in the second edit box. Click the
"Renumber" button to start the renumbering process. Note the Message Warning that
all the files in the directory will be Renamed. The two lower panels
show the directory's files before and after renumbering.
Note that the program can only renumber in date order if the Date part of the filename is spelt correctly and is valid. The program checks that the Date occupies exactly 9 characters - if not, the Date part is set to the file's DOS timestamp (the date and time shown against the file in Windows Explorer).