Questions about Categories

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jonha4711
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Questions about Categories

Post by jonha4711 » Sun Feb 14, 2016 5:33 pm

I am a long-time user of XnViewMP (Windows 7) and quite happy with its functionality. I am now coming to a point where my photo collection gets hard to manage because of the sheer number of photos. I do make judicious use of folders but with 30000+ photos a simple folder structure begins to grow unwieldy.

So I've looked into the various methods to classify and access pics and I think that XnView categories might be my best bet. They are fast because the information is stored in the XnView database and they are completely under my control. Most of my photos deal with my travels around the world, so I would have categories for all the countries, regions, major cities etc. but also broader categories like "people", "mountains", "birds" etc.

This brings me to my main question: will categories scale well if their number increases? I might, when the whole thing is categorized, look at several 100 or even more categories in a complex hierarchical tree. Is that feasible without too much of a performance hit?

Another broader question is whether categories are indeed as good as I think they are. What schemes are other people using and what are the relative merits and problems?

Any help appreciated.

jonha4711
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Joined: Mon Feb 08, 2016 4:35 pm

Re: Questions about Categories

Post by jonha4711 » Fri Feb 19, 2016 9:15 am

Sigh... so I am trying to answer my own question.

It is possible to create, import and export 1000s of categories. And given that apparently sets of categories can contain an unlimited number of categories, I assume that a high number of categories would not create a bottleneck for XnViewMP.

I am still not very clear whether categories are the way forward though. My biggest concern is that if the XnViewMP database gets corrupted the categories are lost. I know that I can synchronize XnViewMP categories with XMP/IPTC keywords but my limited tests indicate that in the case of IPTC hierarchical keyword information can get lost.

I can't be the only one who wants to use such a feature so I strongly suspect others have found a feasible and reliable way to transfer hierarchical keywords/categories between the XnViewMP database and the actual image files.

Erixx haxx
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Re: Questions about Categories

Post by Erixx haxx » Fri Feb 19, 2016 5:32 pm

Maybe this will help from how i understand how xnviewmp works.

-xnviewmp Categories panel is basic the same as keywords of Iptc and xmp. (Not to confuse it with the 3 letter tag named Categories)
-You can embed these into the image or pull them back from the image if previously embedded. ( 3 options here, Read, Right, Ignore )
-Category Sets are just a list of xnviewmp Categories grouped together. Like favorites ect..
-You can backup or copy your database anytime.
-You can tell xnviewmp what and where the real database is stored.
-You can print plain text list of all keywords/categories in the database. (I think even as a tree, but you'll need to confirm this)
-I really think calling "Categories" instead Tags, or Keywords would have been better. (If you notice wording is a problem throughout the program.)
-I'm not sure what the number limits are. probably need to see sql

Like if this happens:
I am still not very clear whether categories are the way forward though. My biggest concern is that if the XnViewMP database gets corrupted the categories are lost. I know that I can synchronize XnViewMP categories with XMP/IPTC keywords but my limited tests indicate that in the case of IPTC hierarchical keyword information can get lost
If keywords are embedded then you can just pull them back from the images. Or make regular backups of the database.
Also make sure you have the proper separator ticked to read as hierarchical. Under meta-data section in options.

Hope some of this helps..

shadowpower
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Re: Questions about Categories

Post by shadowpower » Fri Feb 19, 2016 8:03 pm

jonha4711 wrote:Sigh... so I am trying to answer my own question.

It is possible to create, import and export 1000s of categories. And given that apparently sets of categories can contain an unlimited number of categories, I assume that a high number of categories would not create a bottleneck for XnViewMP.

I am still not very clear whether categories are the way forward though. My biggest concern is that if the XnViewMP database gets corrupted the categories are lost. I know that I can synchronize XnViewMP categories with XMP/IPTC keywords but my limited tests indicate that in the case of IPTC hierarchical keyword information can get lost.

I can't be the only one who wants to use such a feature so I strongly suspect others have found a feasible and reliable way to transfer hierarchical keywords/categories between the XnViewMP database and the actual image files.
make backups and probably use any of the cloud storage service (free should be enough for most of them) then your main concern would be your pc burning down and losing the images (can't easily backup hundreds of gigabytes compared to a gigabyte or two for the categories)

jonha4711
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Re: Questions about Categories

Post by jonha4711 » Sat Feb 20, 2016 8:50 am

Thanks for taking the trouble to answer. Some comments:
Erixx haxx wrote:-xnviewmp Categories panel is basic the same as keywords of Iptc and xmp.
This is almost but not entirely correct. Storing XnViewMP categories as XMP saves the hierarchical relationships, whereas saving them as IPTC doesn't in all circumstances.
Erixx haxx wrote:-You can embed these into the image or pull them back from the image if previously embedded. ( 3 options here, Read, Right, Ignore )
This works (I've tried it with various configurations) but again it is not entirely reliable. Sometimes (I wish I could say when and why) IPTC/XMP keywords are just not copied back correctly after I have deleted the XnViewMP database. The keywords are there but even menu option "View/Update catalog from files" doesn't write them back into the XnViewMP database.

What do you mean with "( 3 options here, Read, Right, Ignore )"?
shadowpower wrote:make backups and probably use any of the cloud storage service
I know that this is an option but my automated backup routines so far never backup data that can easily recreated. I could change that of course but it would mean some significant changes for my setup. But I am beginning to think that simply backing up the XnViewMP database is perhaps the simplest and most reliable solution.

Another idea would be an option to export/import (as CSV, say) a simple list of filenames and category values. Having such a feature would allow additional goodies like mass manipulating the category values with a capable editor (ie one supporting regular expressions).

shadowpower wrote:then your main concern would be your pc burning down and losing the images
: ) This can't happen as I have several full backups in physically different locations.

Erixx haxx
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Re: Questions about Categories

Post by Erixx haxx » Sat Feb 20, 2016 8:23 pm

What do you mean with "( 3 options here, Read, Right, Ignore )"?
Sorry:
I meant (3 options here are: Read, Write, Ignore ) For your sync options under Metadata. iptc & xmp
Also you need to select the correct separator used for sub categories.
This is almost but not entirely correct. Storing XnViewMP categories as XMP saves the hierarchical relationships, whereas saving them as IPTC doesn't in all circumstances.
Yes, and honestly is the reason why I don't use the tree structure for keywords. I found that this can turn into a mess real fast. Especially for other programs.
But , so can the other.
I use a set number of words and the "category sets" instead. Only other option i found was to use only xmp, but some things don't read them. Very few though.
This works (I've tried it with various configurations) but again it is not entirely reliable. Sometimes (I wish I could say when and why) IPTC/XMP keywords are just not copied back correctly after I have deleted the XnViewMP database. The keywords are there but even menu option "View/Update catalog from files" doesn't write them back into the XnViewMP database.
You might be able to solve this by reading only xmp when sync back from files. I'm not sure if we have this option though.

For backups, Manual right click copy seems to work best or me. Maybe a "Dir sync" program set to auto sync would work to auto backups the .db folder.

jonha4711
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Re: Questions about Categories

Post by jonha4711 » Mon Feb 22, 2016 9:43 am

Well, I'll stick with XnViewMP categories and completely ignore XMP/IPTC. I don't know a lot about these tagging formats but first impressions so far are not entirely convincing : )

I am also not quite sure whether the interoperability between XnViewMP and those formats is as stable and reliable as it could be.

I still think that an option to export/import filenames and categories (inlcuding hierarchy information) as a simple text file would be a great idea.

Erixx haxx
Posts: 330
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Re: Questions about Categories

Post by Erixx haxx » Mon Feb 22, 2016 7:32 pm

I don't know a lot about these tagging formats but first impressions so far are not entirely convincing : )
Have you been to the "exiftool" website from Phil Harvey. He has lots of info on these 3 tag types. Exif, xmp, Iptc. Under "Tag names" section.
He keeps up to date and lots of info.

jonha4711
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Re: Questions about Categories

Post by jonha4711 » Tue Feb 23, 2016 10:32 am

Erixx haxx wrote:
I don't know a lot about these tagging formats but first impressions so far are not entirely convincing : )
Have you been to the "exiftool" website from Phil Harvey. He has lots of info on these 3 tag types. Exif, xmp, Iptc. Under "Tag names" section.
He keeps up to date and lots of info.
No, I haven't. Thanks for the hint, I might go there in the future.

For the time being those tagging formats are a can of worms I do not intend to open. I have a very clear and simple need which seems to be perfectly served by XnView's categories and database: I want fast access to images based on their keywords. The DB/categories based solution beats the other options by a mile... the one thing that worries me is the possible DB corruption which I will fight with regular DB backups. Perhaps I will export the category information into XMP or (unlikely) IPTC sometime in the future but for the time being categories seem to work well enough not to merit other options.

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photoken
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Re: Questions about Categories

Post by photoken » Wed Feb 24, 2016 8:49 pm

jonha4711 wrote: I have a very clear and simple need which seems to be perfectly served by XnView's categories and database: I want fast access to images based on their keywords. The DB/categories based solution beats the other options by a mile...
You are correct in your analysis. All other Digital Asset Management programs make use of their hierarchical categories stored in their database to classify, access and search for images because of the speed and precision that method offers.

XnViewMP is lacking one very important search feature, however -- the ability to search for images which do NOT have a specific category. In other words, you can build a search for images which have the categories "Germany" AND "Mountains", but you cannot build a search for images which have the category "Germany" and NOT "Mountains". I filed a request for this many months ago, but it has not been implemented. :(
Ken
Yes, I think it can be eeeeeasily done...
Just take everything out on Highway 61.

jonha4711
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Re: Questions about Categories

Post by jonha4711 » Thu Feb 25, 2016 4:45 pm

photoken wrote:XnViewMP is lacking one very important search feature, however -- the ability to search for images which do NOT have a specific category
Yeah, I've already noticed that. In general, the search dialog is a lot less powerful than it could be. For instance, currently conditions are evaluated either all or any... that is rather limiting. It would be great if conditions could be linked with AND OR NOT.

But hey, XNView[MP] is free for personal use and I do not complain : )

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xnview
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Re: Questions about Categories

Post by xnview » Fri Feb 26, 2016 7:50 am

photoken wrote: XnViewMP is lacking one very important search feature, however -- the ability to search for images which do NOT have a specific category. In other words, you can build a search for images which have the categories "Germany" AND "Mountains", but you cannot build a search for images which have the category "Germany" and NOT "Mountains". I filed a request for this many months ago, but it has not been implemented. :(
yes, but how to do that in ui? by selecting category in the treeview, we can have AND/OR, but how to represent NOT
Pierre.

jonha4711
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Re: Questions about Categories

Post by jonha4711 » Sat Feb 27, 2016 2:39 pm

xnview wrote:
photoken wrote: XnViewMP is lacking one very important search feature, however -- the ability to search for images which do NOT have a specific category. In other words, you can build a search for images which have the categories "Germany" AND "Mountains", but you cannot build a search for images which have the category "Germany" and NOT "Mountains". I filed a request for this many months ago, but it has not been implemented. :(
yes, but how to do that in ui? by selecting category in the treeview, we can have AND/OR, but how to represent NOT
Well, there are actually two issues here: one is photoken's assertion that it is not possible to NOT search for categories.

The second is my assertion that the general Search dialog in XnViewMP is relatively simplistic. This would be easily (I know, it is not THAT easy) fixable if separate conditions could be linked/prefixed with keywords AND OR NOT. This sort of thing offers, like regular expressions, certainly a more complex interface but it would enable incredible powerful searches.

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photoken
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Re: Questions about Categories

Post by photoken » Mon Feb 29, 2016 6:05 am

xnview wrote:
photoken wrote: XnViewMP is lacking one very important search feature, however -- the ability to search for images which do NOT have a specific category. In other words, you can build a search for images which have the categories "Germany" AND "Mountains", but you cannot build a search for images which have the category "Germany" and NOT "Mountains". I filed a request for this many months ago, but it has not been implemented. :(
yes, but how to do that in ui? by selecting category in the treeview, we can have AND/OR, but how to represent NOT
The Search dialog would be like this:
category search.jpg
category search.jpg (68.93 KiB) Viewed 3389 times
  • The "Match All" and "Match Any" entries would be eliminated.
  • Each line of criteria would be followed by a dropdown selection box containing three items that refer to the following line of criteria:
    • AND
    • OR
    • NOT
Ken
Yes, I think it can be eeeeeasily done...
Just take everything out on Highway 61.

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oops66
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Re: Questions about Categories

Post by oops66 » Mon Feb 29, 2016 9:17 am

XnViewMP 0.82 Linux X64 - Ubuntu 16.04 LTS - X64

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