Python:Images

Images can have meta-data embedded. Most used is Exif[1], other formats are IPT[2] and XMP[3].

It appears that exiftool is the way to go. PyExifTool is a python wrapper for it.

In Debian exiftool is provided by libimage-exiftool-perl. That is automatically selected when you apt install exiftool.

PyExifTool is not available as a Debian package. Install it in a Python#Virtual_environment

from exiftool import ExfiToolHelper

ExifToolHelper is a wrapper for ExifTool with some helpful functionality.

et = ExifToolHelper()

Instantiate an ExifToolHelper object. It opens an instance of exiftool in batch mode. Exiftool in closed when the object is terminated

et.terminate()

Destroying the ExifToolHelper object terminates the exiftool instance.

with ExifToolHelper() as et:

Automatically terminate the ExifToolHelper object at the end of the block

et.get_metadata(<filenames>)

Get all metadata from <filenames>, <filenames> can be a single path or a list of paths

Returns a list of dictionaries {<tagname>:<tagvalue>,..}. <tagvalue> can be any type.

et.set_tags(<filenames>, tags={"Subject": ["Holiday", "Spain", "Trees"]})

Set the XMP:Subject tag in <filenames>.

Example code:

from exiftool import ExfiToolHelper
import json

with ExifToolHelper() as et:
    metadatalist = et.get_metadata(filename)
    for metadata in metadatalist:
        for tag, value in metadata.items():
            print(f"{tag}: {value}")

# Set IPTC:Keywords (not shown by Debian eog (Afbeeldingsweergave in Dutch))
with ExifToolHelper() as et:
    et.set_tags([filename], tags={"Keywords": ["sunny", "nice day", "cool", "awesome"]})

# Set XMP:Subject  (XMP is newer than IPTC, I prefer to use this)
with ExifToolHelper() as et:
    et.set_tags([filename], tags={"Subject": ["Holiday", "Spain"]})