Picasa 3.5: how to share the tagged faces from one PC to another

At home, we share our photos from a server. I've been tagging the faces in Picasa 3.5 in one PC, but in the other PC the same photos needs to be retagged.

Where is this info stored so it can be shared between computers?

Picasa stores face tag information in a database file and a .picasa.ini file. Both can be found in the directory where the images reside. To find where your images are, right click one and select "locate on disk".

The face tag information is stored in .picasa.ini files. Although the tags are actually references to contacts that are stored in user's directory. On my PC (Windows Vista) the contacts are stored in %LocalAppData%\Google\Picasa2\contacts\contacts.xml file. The contacts can be local (sync_enabled="0" in the XML file), so there is no need to sync with the web server.

So, if you synchronize your contacts.xml between your PCs the face tag information should be synchronized as well. The question is how to do it. This howto describes how to share picasa data between multiple accounts on same PC. Ideally picasa local data should be put on the same server where you store your pictures and then %LocalAppData%\Google\Picasa2* directories are to be linked to the remote directories. Unfortunately I don't know a way of creating links to remote shares. NTFS junctions obviously don't work in this case. I'm not a Windows expert though. If you can't link to a remote share, you will have to synchronize your picasa folders in some other way.

Update: just found a "WinXP - Map network location to local folder" (can't post a link because I don't have enough reputation points) thread on serverfault.com. Conclusion there is that you can't map a shared folder to a local folder (not a drive letter).

For information, I created a little application that gives a solution to this problem. To be found here: http://sites.google.com/site/picasastartersite/home

This is the response from an actual Google Picasa team member, according to www.digitalhomethoughts.com:

A: There are a few different ways to transfer your face tags:

1. You can perform a Backup of your photos and restore them on your new computer. This process will preserve your face tags. ("Tools" > "Backup Pictures")
2. You can copy your files and the .picasa.ini file from your hard drive to the new destination
3. Upload your face tag albums to Picasa Web Albums and download the album to the new destination

*Important note on option 3: In order for your contact information to be preserved you'll need to make sure that your contacts associated with your face tags are marked as "Online Contacts." This means that the person is synchronized with Google Contacts. After copying the photos to the destination computer, make sure you are logged in to your Google user account so that Picasa can retrieve your Google Contacts and update your face tags with the corresponding information. See reference section for more info on syncing contacts."

Also, the Picasa team is supposedly working on a more portable implementation of face tags.