Usage

As a Python module

Simple usage

You only have to import pyimgren and create a Renamer:

import pyimgren

ren = pyimgren.Renamer("/path/to_folder")      # use default options here

and that’s all…

You can then use the rename() and back() methods to rename pictures forth and back:

ren.rename()      # rename all files in the folder matching DSCF*.JPG
...
ren.back("20160910*.jpg")  # only rename back pictures taken on 10/09/2016

Mid-level usage

All messages from the pyimgren module go through the logging module. If you want debug messages to be actually printed, you must configure a non default handler processing that level before using rename() and back() methods with a debug=True parameter:

log = logging.getLogger('pyimgren')
log.setLevel(logging.DEBUG)
log.addHandler(logging.StreamHandler())
...
ren.rename(debug=True)           # ok, debug messages will be printed

You can automatically process sub folders. If thumbnails is a subfolder of the current folder, you can use:

ren.rename("thumbnails")

This will automatically start a new Renamer in thumbnails with the exact same options as ren and call rename() on it. But beware:

• this will process all files matching the src_mask parameter of ren
• this will create a names.log file (or more exactly a file for which the name is the value of the ref_file parameter) in the thumbnails directory.

Long story made short, it can make sense and is actually used in the command line interface, but it does not allow to process folders that are not descendant from the ren folder, nor to specify a limited list of files.

Advanced usage

If you want to build a complete front end for pyimgren, you will probably be interested by the others methods from Renamer and the function exif_dat().

This last one tries its best to extract an exif timestamp from a file and returns None if it could not find one. You can use it to easily build a dictionary {file_name: exif_timestamp} from a list of picture names:

dd = { file: exif_dat(file) for file in files }

It is guaranteed to never raise an exception.

The other methods from Renamer, namely load_names() and get_new_name() respectively load the names of pictures which have been renamed (both new name and original one), and find what would be the new name of a file with respect to the a to zz suffixes. Examples:

# build a list of all files in the folder with their original name
names = ren.load(names).items()

or:

file_name = ...
dat = exif_dat(file_name)
if dat is not None:
    new_name = get_new_name(dat.strftime(ren.dst_mask) + ren.dst_ext)

From the command line

The package provides a command line interface to the Renamer class.

Syntax:

usage: pyimgren [-h] [-v] [-b] [-s SRC_MASK] [-d DST_MASK] [-e EXT_MASK]
                [-r REF_FILE] [-D] [-X]
                folder [files [files ...]]

Rename pictures according to their exif timestamp

positional arguments:
  folder                folder containing files to rename
  files                 files of sub folders to process (optional)

optional arguments:
  -h, --help            show this help message and exit
  -v, --version         show program's version number and exit
  -b, --back            restore original names
  -s SRC_MASK, --src_mask SRC_MASK
                        pattern to select the files to rename
  -d DST_MASK, --dst_mask DST_MASK
                        format for the new file name
  -e EXT_MASK, --ext EXT_MASK
                        extension for the new file name
  -r REF_FILE, --ref_file REF_FILE
                        a file to remember the old names
  -D, --debug           print a line per rename
  -X, --dry_run         process normally except no rename occurs

This internally starts a Renamer with the options passed as parameter. If option -D|--debug is present a StreamHandler is configured to process Debug level message in the logging module. Then, the Renamer runs its rename() method if the -b|--back option is not present, else the back() method.

Special case

On Windows, the Python script directories are commonly not in the PATH, and users use the py launcher to start the interpretor or the scripts. In that case, the pyimgren package can be started from the command line as a module:

usage: py [py options] -m pyimgren [-h] [-v] [-b] [-s SRC_MASK]
                [-d DST_MASK] [-e EXT_MASK] [-r REF_FILE] [-D] [-X]
                folder [files [files ...]]

The parameters are exactly the same they were for the script.