Re: [help-GIFT] Adding images during runtime (was: future features)

[Wolfgang Müller]

Hello, Ernesto,
> I'd like to use GIFT for a new-media application I'm working on, and I'd
> like to know how GIFT behave with the following:

> - how do I add new images to an already existing collection?

Currently the way to go is to run gift-add-collection.pl again. This is not 
runtime.

> - is it possible to add those new images runtime?

"Possible" has two possible meanings.

1. "Possible with the current code?"

No, the current code does not support runtime adding of images.

2. "Possible at all?"

Yes, of course. http://portal.acm.org/citation.cfm?doid=1099739 seems to me a 
good way to go, if you want efficiency. If efficiency is not a major concern, 
it might be a good idea to do some double-buffering kind of approach:

When generating a new inverted file for a collection that has been indexed 
before, you do so without touching the original inverted file.  Once the new 
inverted file is generated, you simply mv the new inverted file over the old 
one. 

In addition to that, you check at each query, if the modification time of the 
inverted file has changed. If so, you reread the inverted file before 
processing the query.

I have been asked for this a couple of times, lately, but I was too swamped to 
respond properly. If you are interested in getting this solved, please use 
this list to get an effort in this direction going. I will be glad to help by 
answering questions.

Cheers,
Wolfgang

-- 
Dr. Wolfgang Müller
LS Medieninformatik
Universität Bamberg
Check out the SIG MM web site http://www.sigmm.org