Any support for Custom tags?

[joe]

Hi. I've seen a few posts that seem to indicate that there is no support for custom tags in general. My question is whether there is any way to provide a sort of "pass-through command" to ExifTool at least for manipulation of a custom tag.

My thinking is that I could still place a config file where ExifTool is stored to enable the custom tag I want. ExifTool then knows about my tag through a simple string reference as with all other tags. I could then use a pass-through command to allow my automation through an app to keep the relative context between a custom tag and other standard metadata that IMatch knows about. Is anything like this possible? Thanks.

[Mario]

IMatch and ExifTool currently support over 15,000 tags
What is your definition of "custom tag" and why would you need to work with custom tags probably no application out there recognizes or supports, including IMatch? That's a step that has to be really carefully considered.

In order to add and work with custom tags with ExifTool they need to be defined in an ExifTool config file and this config file must be provided as a command line argument to ExifTool. Only one config file is supported and IMatch already uses this feature to deal with some extended IPTC tag and some other tags used mostly by commercial customers.

You can always call ExifTool directly from the command linke, providing the custom configuration file with your custom tags and values for these tags, if you need this. IMatch will not know about the custom tag since it retrieves tags and groups directly from ExifTool, which does not include the tags you define in your custom configuration file.

Have you considered storing your custom data in the vast number of XMP tags? Or in IMatch Attributes?
Attributes are like super custom tags, working across all file formats. You can store any amount of data in them.

[joe]

Thank you, Mario. As for my use case, in case you know of a relevant field, I do a lot of genealogy work where with many photos people don't know the actual date, but often they can place it within a date range - could be a year, a month, the summer, etc. I've created a "code" to encode many types of date ranges, and that's the value of my custom field - to represent fuzzy date ranges. Do you know a field that feels relevant for this concept?

I'm currently using XMP Custom1 but figure that other people out there are probably using the XMP custom fields as well, so I should have a custom tag as a backup with duplicate data. I've created an IMatch app that allows one to enter/modify the fuzzy date. It currently writes Custom1, and I was hopeful it could write my custom field as well.  That was my current plan. I didn't realize IMatch was using the configuration file.

Still being somewhat of an IMatch novice, I had not delved into attributes yet. Looking them over, I'm thinking they could work for this, since I'm mainly thinking about this custom field as a backup and since there's an API for attributes through IMatch.

[Mario]

Attributes are a very good way to setup and store custom data of any kind.
They are searchable, accessible via variables, work for all file formats, are accessible for apps and so on.

I have seen many files were uncertain dates were included as part of the description, especially in scientific environments. Usually as the first or last line in the description.
You can of course also use the title (which is often only used to store a copy of the file name). Which leaves the headline and description tag for everything else.

It all depends on with whom you are exchanging your data.
The Darwin Core XMP schema is often used (and has been designed for) scientific purposes. It has an EventDate tag that takes a date or a date range, for example. Which covers uncertain dates.

IMatch supports the Darwin Core XMP schema. You can include selected tags of it in your custom MD Panel layouts.