Image Tags Format

cjm51213

Hi Folks,

There are apparently a few different formats for image tags: EXIF, IPTC, and XMP, among them. Which format should I use?

Thanks for the help,

Chris.

cjm51213

Hi Folks,

I've made an assumption in this post. I assume that I can, for example, tag a set of images, "Dad's 75th Birthday", and collect them together in a "Dynamic Album". Is this true? Is there a preference for which image tag format I use? IPTC seems flexible, and XMP is even in XML, but neither is any good unless zenphoto can support this "Dynamic Album" idea.

I know that zenphoto has a "tags" feature, but I have enough that I will probably have to use a script and some editing utility.

Thanks for the help,

Chris.

kuzzzma

You can use all three of them.
EXIF and IPTC work out of the box, for XMP you need to enable xmpMetadata plugin (comes with the install, needs activation)

Tag and a Dynamic album based on it - will work, very common scenario.

acrylian

What kuzzzma said. You can create dynamic albums per script if needed for that many. They are basically text files with specific content. Create one manually for a tag to see what you need to generate.

Also enable the html_meta_tags plugin. Depending on your site structure you may want to set some settings. Theoretichally dynamic albums can create duplicated content as they reference images from other albums that basically would have multiple pages with the same content then.

cjm51213

Hi Folks,

Thanks for the clarification.

I'm not at all clear on the whole script methodology acrylian mentions, but when I get to that, I'll have a clearer misunderstanding. (-:

I think I have a final question. Can I create tag aliases? For example. let's suppose I am not completely consistent about labeling a person. They are known by a few names. Maybe they have a maiden and married name, or a nickname. Can I declare an alias somehow that identifies both tags as the same tag? Or do I simply find all the "old" tags and change them?

cjm51213

Hi Folks,

EXIF and IPTC have "expandable" schema, but it appears to be awkward and poorly supported, in general. However, XMP seems purpose built. For example, I could have an event, "Build the House", and "subevents" "Pour the Concrete", and "Erect the Framing", and I should be able to display my content by either the superset, "Build the House" or either of the subsets. Am I right about this much?

My question, now, is, "How do I describe the schema so zenphoto knows about it?". I see that the schema is described with an XML file, and I assume that all I have to do is put it in the right place. Is that right so far, or does this require an XML file for each image?

acrylian

Zenphoto tags do not support hierachy. You have to assign every tag you wish an image or album to appear with.

cjm51213

Just so I am clear, when you say "Hierarchies are not supported", do I understand that zenphoto simply does not parse and understand hierarchy described in the metadata, and an image will not "inherit" a tag through hierarchy?

Suppose I tag an image with two event tags. Will it appear in both “Dynamic Albums”? Meaning if I tag an image “Christmas” and “Christmas 2023”, I can have a dynamic album for each, with “Christmas 2023” being included in “Christmas”? If this is true, then I can create the hierarchies in the set of tags.

This leaves me with questions about the numbers of tags… Can I have multiple “Event” tags? How many is “multiple”? I’m thinking about group pictures, which can easily have dozens of subjects and I would want to tag each person ...

kuzzzma

I can answer some, but not all:
Keywords:
I use Lightroom for tagging my photos, with keywords in hierarchy within it (for example, Events>Event1, People>Family>Person 1, People>Friends>Person 2).

I believe, on Export from Lightroom they are written as:
Events, Event1, People, Family, Person 1, Friends, Person 2

Zenphoto imports them this way too.

So all tags within hierarchy are present, but in a plain list.

How many Tags:
No limit, I believe.
I tag my stuff extensively, and never had any problems.
Might take longer to process image on import or page on display though.

If you use a really tremendous amount of them - probably avoid listing ALL the tags in the database for all the photos, but a lot of tags for a single image may pose only a problem for theme design.

One of my sites currently has around 3000 tags and page with all the tags takes a second to populate the list.

Dynamic albums:
It's stated in gallery manager that you can't have subalbums to a dynamic album (either normal or dynamic), as effectively a dynamic album is just a preserved search with different parameters, so it can't have a child directory for it with physical files.

Maybe it's possible to code smth to make a sub-dynamic-album for a dynamic album, but I've never tried.

You can have a physical directory though with multiple dynamic albums within. So, for your case with events it may be:

/Events - actual album on server
--dynamic-album-file-with-search-for-tag-event1
--dynamic-album-file-with-search-for-tag-event2
--dynamic-album-file-with-search-for-tag-event3

acrylian

Yes, tags in Zenphoto are flat. And before you ask it is not planned to change that in the near future.

You need to understand the two album types:

• The real physical albums representing a folder on the file sytem as Zenphoto is file system based
• Dynamic albums which are saved searches as tags are technically a specific search in Zenphoto.

t's stated in gallery manager that you can't have subalbums to a dynamic album

Well, you can tag albums accordingly and if you have album results enabled for search you technically can have albums within a dynamic album. It is not the same as a hierachy though.