Face recognition two computers

[Stefanjan]

Still trialling imatch and trying to figure out how to best use people keywords.

My image folders sync in real time between my Windows 10 Desktop and Windows 10 laptop via a Synology NAS using Resilio Sync.

I am quite impressed with imatch face recognition which I have been testing on a small test database.

Questions:

1. Will face recognition sync automatically using xmp between my desktop and laptop or are their manual steps I need to take.

2. Does face recognition create standard xmp keywords. It doesn't seem to in my test.

3. What formula would I need to create a WHO category using face recognition.

4. I saw a warning about not automatically saving XMP meta data. Is there anywhere I can read up on the risks and precautions I should take.

[Mario]

IMatch stores metadata, including face regions, in the database primarily.
If you write back metadata, IMatch produces XMP face regions automatically. See Working with XMP Face Regions
Keep in mind that XMP support for faces is rather limited.

2. Yes.

3. IMatch displays all persons in your database in the People View. There is usually no need to produce yet another data-driven category.
To create a data-driven category, I recommend doing so based on one one of the Persons. Variables

4. IMatch by default does not immediately write-back metadata. This would be a bad performance drag and is usually never needed.
Metadata Write-back

If you sync your images to multiple systems by copying them, you should a) also sync the database and b) write-back all modified metadata in IMatch before copying the files.

[Stefanjan]

IMatch stores metadata, including face regions, in the database primarily.
If you write back metadata, IMatch produces XMP face regions automatically. See Working with XMP Face Regions
Keep in mind that XMP support for faces is rather limited.

I see. If my desktop saves a face region and the file syncs. Wouldn't this mean my laptop loads the face region from the synced file?


No 2 So the name should appear in the keywords panel. I'm not always seeing it. Does the keyword need to be in the Thesaurus to appear?

If you sync your images to multiple systems by copying them, you should a) also sync the database and b) write-back all modified metadata in IMatch before copying the files.

I don't m manually copy the files. Resilio sync copies them immediately when they change.
I can sync the database but I guess the file paths need to be exactly the same on both computers. And also I imagine have to contain exactly the same folders? Currently on recent years sync to my laptop.

I guess I could map NAS folders on my laptop to match the mapping on my desktop which currently has photos on SSDs and Hard drives

[Mario]

Wouldn't this mean my laptop loads the face region from the synced file?

Load into what? A new IMatch database? Yes, the face regions are imported as described in the help topic I've linked too. PLEASE read the info I link to, I don't post links just for fun.

No 2 So the name should appear in the keywords panel. I'm not always seeing it. Does the keyword need to be in the Thesaurus to appear?

No. When you assign and CONFIRM a person, the keywords are added. Please check what you are doing and that you understand how this works. Again, read the People help topic, which has all the details and explains how person keywords are used.

I don't m manually copy the files. Resilio sync copies them immediately when they change.

That does not help much, does it? You also need to write back the metadata into the file before you let the software copy it. Else the file will be copied with unchanged metadata.

I can sync the database but I guess the file paths need to be exactly the same on both computers.

Off-line Folders and Files

You can even make IMatch automatically relocate folders when the database is opened on a new machine. Portability Options

Accessing files over NAS and network is the slowest possible use case.

[Stefanjan]

Load into what? A new IMatch database? Yes, the face regions are imported as described in the help topic I've linked too. PLEASE read the info I link to, I don't post links just for fun.

Sounds like I've toughed a nerve! I have read all the links you provided. I'm sorry if it's not all as clear to me as it is to you. I'm trying to learn and understand what I'm sure is a very useful but powerful piece of software.

I'm finding it difficult to understand some of the basic concepts e.g. https://www.photools.com/help/imatch/#md_writeback.htm implies that at some time imatch will write back the meta data but my installation doesn't seem to write back the meta data unless I click the pen.

Trying to understand the workflow around ensuring meta data gets saved so I can view it in other applications.

It also doesn't seem to reload changed meta data unless I rescan. This is probably not an issue as I understand that I should only change meta data in imatch. You have also provided the link to tell me how to work with the same database which is synced between two computers which I need to test but sounds perfect!

[Mario]

You did not hit a never. But when I have to type the same info over and over again that is already covered in detail in the IMatch help, it is a waste of time.
Like, in your case, how IMatch recreates face annotations from XMP regions written by other software. IMatch itself usually does not need to do this, unless you lose your database - which contains all the face info and related data. XMP can hold only a small subset of the rich face and person data IMatch holds in the database.

Restoring faces from XMP is only needed if you have lost your database or to bring in face recognition results produced by other software. Else, always copy your IMatch database. This saves a lot of time because IMatch does not need to re-run face recognition on all imported XMP faces.

IMatch does not by default write-back metadata unless you trigger it (via the pen icon in the File Window) or the Commands > Metadata Write-back commands.
Immediately writing back metadata after every small chance you did can be a major performance drag. And could possible explode your daily backup volume. This is why this is off.

When you copy files with new face annotations before the metadata is update, neither the new face regions or the associated keywords or any other modified metadata will become part of the copy.
If you use this kind of workflow, consider enabling the immediate write-back under Edit > Preferences > Background Processing and make sure your backup copy does copy the files after they have been modified, not before.

It also doesn't seem to reload changed meta data unless I rescan.

IMatch automatically rescans folders when the "last modified" timestamp on disk has changed.
Or, when IMatch is running, when Windows sends "Folder and File modified" messages.

IMatch also waits for short while after it has started before it checks all folders for modifications.
If this does not work on your other PC, check that your copy software actually updates the last modified file system timestamps of the copies. Else IMatch has no way to tell.

[Stefanjan]

Thanks Mario, I have tested syncing the database between two computers and it works perfectly.

In my testing providing I close the databases then imatch successfully syncs face and keyword metadata between the two computers.

In this scenario there is therefore no need for me to write metadata back to the files.

If I have the database open on either computer then the sync software will wait before syncing because .imd5 and .imd5-wal are both locked.

I have to say that I am very impressed as to how clever this software is.

By the way, on my desktop PC I have a couple of EVO 970 NVMe M.2 SSDs, the database is on one with the cache on the other.