Digikam/Tutorials/Tagging and Face Tags

    From KDE UserBase Wiki
    Revision as of 14:36, 8 January 2021 by Sdx (talk | contribs) (→‎Geo location: updated & added link to another tutorial)

    What is Tagging and why do you want it

    digiKam is an excellent tool to enrich a private photo collection by use of Tags and other metadata that can be written right inside the image files so the information you add follows the image file and will not get lost if you change computers or software (alternatively digiKam can save metadata in "sidecar" helper files next to your videos or read-only image files).

    Tags in your photo collection work the same as #hashtags on the Internet – they help you to find all your images that belong to the same category that you provided: locations, names of people, events (birthday, national day…) or anything that is meaningful to you (for example pictures that contain Lego; your 2nd car; sunsets; etc.).

    In addition you can mark specific regions on the picture as “Face tags”, add descriptive text, rating from 1 to 5 stars and some more metadata types. All of this needs to be worth-it – add data that you will realistically want to search and filter your collection on. Plus remember that you already have photo date, folder name where the photos are located (which is hopefully meaningful) and possibly even geographical coordinates embedded in your image files even before you start adding any tags.

    Working with Tags can be as simple as marking location, who is in the picture and giving 4-5 stars to really nice pictures. Perhaps you will see an existing Tag hierarchy in your digiKam that was built based on Tags that were found in the images that you already have (those tags may come from your relative, friend or even some software and you are free to use those tags as an example or build your own system). On the other extreme metadata can get almost scientific with rules, data models and words like “Digital Asset Management”. When you are ready to try adding some tags, continue with this tutorial on How to do it.

    Recently machine learning "AI" algorithms are doing more and more photo classification fully automatically, without any manual Tagging needed. Still you can decide yourself how much manual tagging is worth it and what can be guessed by an algorithm. Note that digiKam also includes some similarity search tools and other clever algorithms which will evolve in the future to provide more value and easier search in your private photo collection.

    Don't Forget Privacy

    Remember to strip your tagged images of all metadata before you share them to people who do not understand metadata. Any metadata that you had or added in digiKam including GPS location, tags, people names, etc. will follow the image file when you share it on the internet or send to someone (unless you use some tool to remove the metadata before sharing).


    Warning

    The default metadata related settings in digiKam may not be optimal for your use-case. It is worth understanding what exactly is digiKam reading from files, saving to files and which files are supported. These details need to be covered in another tutorial. If you start tagging your files with sub-optimal settings in digiKam it will not break anything, but can leave some "garbage" in your files that could be avoided.


    Main Tagging tools in digiKam

    In the current version of digiKam (7.2+) it can be a little bit complicated to find all the metadata tools and toolbars, but thankfully there are excellent keyboard shortcuts that will both help you find all the necessary toolbars and also make entering information very efficient if you choose to remember the shortcuts.

    The main metadata tools
    Tags: T (re-configurable)
    Face Tags or people tags: Ctrl + drag a box around a face
    Star rating: Ctrl + 0Ctrl + 5 (re-configurable)
    Edit Comment: Alt + Shift + C (re-configurable)
    Edit Title (not recommended): Alt + Shift + T (re-configurable)
    Pick Label or Flag: Alt + 0Alt + 3 (re-configurable)
    Color Label: Ctrl + Alt + 0Ctrl + Alt + 9 (re-configurable)
    Edit Geo location: Ctrl + Shift + G (re-configurable)
    Edit Metadata (lots of fields): Ctrl + Shift + M (re-configurable)
    Rename file (lots of options): F2 (if you have RAW files, be carful renaming only JPG files)
    Rename folder: Shift + F2 (affects folder on your disk)

    + There are more tools such as “Adjust Time & Date” – see the menus and keyboard shortcuts.

    Tip

    When you know what you are doing, it may be a good idea to tick the “Always apply changes without confirmation” checkbox next time the “Apply changes” dialog appears (after you edit metadata in the right sidebar). This confirmation dialog is great to protect against unwanted file metadata changes by unprepared users.


    Tags – How To

    To add a Tag – just press T when you have a picture selected. This will immediately open the right toolbar and you can start typing in a tag. Auto-complete will help you find the right spelling to match existing tags, or you can define a new tag.

    When the “Tags” tab is open you can also add/remove tags by using mouse.

    Important

    Please make sure that you have Toggle AutoParent option selected - see screenshot below. This setting is essential to avoid braking Tag Hierarchy by only selecting a sub-tag, without ticking the boxes also for the parent tags. By default in v7.2 this setting is not optimal for most workflows.


    Tag tab showing example hierarchical tag structure and how to set “Toggle Auto = Parent”' option. NOTICE how in this screenshot the tag Hierarchy is broken because there is a check-box in front of "City Name 1" but not in front of the parents "Country 2" and "- Location"



    Organize tags:

    • Build/edit tag hierarchy (good idea!) - you can drag and drop tags onto each other to “Move here” and create tags and sub-tags. For example Place “Family X home” under “City Name” to get a basic hierarchy.
    • Rename tags – right click any tag and select Properties and edit tag “Title”.
    • Delete tags – note, if you Delete a tag, it will be removed from all files that ever used it!
    • Assign keyboard shortcut to a Tag – it is possible to add a unique shortcut key to directly assign frequently used tags.
    • Changing icon – each tag can have a custom icon (the icon will not be valid outside your digiKam, so do not spend too much effort on this).

    digiKam will propagate the change across all image files that used the old name.

    Note

    digiKam always try to apply your updated tags to all managed files if you change tag hierarchy; re-name, merge or delete a tag. It will affect all files that used those specific tags previously. Still depending on your settings you may need to force “Write Metadata to File” to fully apply the changes.


    Face Tags – How To

    Face or People tags are excellent to show not only who is in the picture but also which one out of all those wedding guests is that person you are looking for. Note that digiKam is unique among open-source and multi-patform photo galleries to feature full support for face regions (including imported face tags from other software) – as always digiKam saves your efforts into formats that will be readable by other software and the data stays safely embedded in each image file.

    Automatic face detection module in DigiKam is working and being actively developed. It can help you tag people without any privacy concerns of the “free cloud services” such as Google or Facebook. The use of automatic face detection is outside of the scope of this tutorial, but it is highly recommended to use the automatic detection first and then compliment people tagging with manual face tagging.

    For effective manual people-tagging use Ctrl + drag a box around a face shortcut. This is a must-know shortcut that beats any other method for adding face tags.

    Face Tag visible on the image and in the Tag tab


    Note

    You do not have to draw a box around every face to add people tags on every picture. If there is no need to specify who-is-who, you can add (and remove) People tags using the same T shortcut from keyboard only.


    Comments, Captions Description and Title

    You can use the “Captions” (and “Title”) field to write a text description about the photo or video which does not have the same limitations as the filename. I do NOT recommend to use both Title and Captions fields together as it may cause compatibility issues with other software, including loss of the contents for one of the fields. Shortcut to quickly find the field: Alt + Shift + C

    Comatibility warning

    Some software supports only one descriptive text field and will erase your “Title” metadata if “Captions” metadata is present in the file. For example Microsoft Windows Photo Gallery (WLPG) is known to do that.


    Star rating

    The classic 5-star rating feature. Quite widely supported and reasonably easy to interpret. You can find guides and suggestions how to use this scale or think of your own.

    As an example, here is one way to interpret stars, as used by me:

    0 stars Not yet rated
    1 star To Delete (not deleted for some reason)
    2 stars Weak photo (useful for context, or completeness)
    3 stars Good photo (nice to show to people)
    4 stars Very good photo (“best of”)
    5 stars Outstanding photo (“work of art”)


    Pick Label (flag) and Color Label

    This type of labeling is quite individual and open for interpretation, so there is a risk that nobody except You will ever understand the meaning of your flags and colors. Still the feature is included in digiKam and will be written into the files.


    Geo location

    Geo-tags is a big topic where besides manual coding there is also special hardware or GPS-enabled cameras (like most smartphones) that can help recording GPS data into your image files. DigiKam supports Geo-tags and map view, please see this tutorial for a proper introduction: Geotagging in digiKam (with Reverse Geotagging). Shortcut: Ctrl + Shift + G.

    Note

    Some people use normal Tags T to create descriptive tags about location as an alternative to actual geographic tags. Without geo-tags there will be no way to see a map view, but it may be an acceptable compromise.


    Author, copyrights and other Metadata

    If you wish to add other metadata, you are welcome to use “Edit Metadata” tool with a shortcut: Ctrl + Shift + M.


    ”The batch-click way” method for quicker tagging

    Peter Albrecht described his digiKam tagging workflow with focus on efficiency that may help you gain speed and efficiency.

    1. switch to thumbnail view (you have to be able to select more than one image)
    2. shift the preview size to the maximum of 256 pixel (you want to be able to recognize the people on the photos)
    3. switch the right side-view to Caption/Tags and select the tab Tags
    4. select picture number one and look at the leftmost person on this picture
    5. hold Ctrl down and select all other pictures, showing this person
    6. search for the corresponding tag in the right side-view, select it and apply.
    7. if there are more persons in picture one, then select this picture again go to step 5, while looking for the next leftmost person.
    8. if you have all the persons in picture one, select picture two and look again for the leftmost person, you have not tagged yet, and go to step 5. (toggling the button tags already assigned in the lower right corner of the Tags tab, is very useful here)

    This way you go through all your pictures. In the beginning you have to tag a lot of people, but coming to the last pictures, most people will already be tagged and you can fast jump to the next picture.

    Tip

    For faster tagging try using keyboard shortcut T and auto-complete when you start typing.


    About this tutorial

    This tutorial is based on and is made to supersede the older tutorial from 2012: Tag your Photos (with focus on efficiency).
    You are very welcome to edit, update and Upgrade this tutorial page to make it better. No attribution or copyrights in this page!