Mounted and Unmounted Images and Local Thumbnails

The whole issue of mounted/unmounted images and local thumbnails is best explained by first looking at the problem and then how these features provide a solution. There are in fact two problems. First lets suppose you have a folder C:/images and then below that a couple more; say C:/images/2002 and C:/images/2003 that actually contain your images. These images have been imported into ImageDB and categorised etc. Later you decide you want to move them from your C: drive to a CD. If you simply burn them onto a CD and then delete them from the C: drive ImageDB will squawk frantically next time you run it because it will not be able to find the images. The solution is to first unmount the C:/images folder. This is done from the Edit/Folder Organisation menu option where you can navigate to the C:/images folder and select Unmount. Now ImageDB will no longer expect to find this folder and its images and will not look for them. You now burn them onto the CD (keeping the same folder hierarchy - /images/2002 and /images/2003) and delete them from the C: drive. Next time you want to view these images insert the CD and remount the images folder; also done using the Edit/Folder Organisation menu option. ImageDB will ask you to locate them allowing you to browse to the CD location. You will now be able to view them as normal. The second problem is very closely related; suppose you have many images on many CDs. You cannot have all of them in the CD drive at the same time, so how can ImageDB know which images are available at any particular time? The solution is to unmount each CD of images when it is not present and only mount the CD that is currently in the drive.

Now to local thumbnails. This is a very closely related problem. ImageDB can create thumbnails for all your images, these can be created in two different ways either locally or with the main image. We will look at the second option first. If the thumbnails are created with the main image they will be created in the same location (folder) as the main image but using a name with a user defined prefix or suffix (set in View/Options). Using this technique you may have an image in C:/images/2002 called fred.jpg and its thumbnail will be created in the same location (C:/images/2002) as _tn_fred.jpg. This can be useful if for example you want to set up a thumbnail page in a web HTML page that displays the thumbnails and links to the actual images. However this is not so useful if the images are on a CD; now if the CD is not present and has been unmounted (see above) then ImageDB will be happy and will not look for the images. Unfortunately it also won't be able to access the thumbnails and so will display no thumbnail for the unmounted images, instead it will just display a box that says the image is currently unmounted. Maybe this is fine but it is quite likely that you would prefer to at least view the thumbnails of images stored on a CD even if the CD is not currently in the drive and is unmounted. The only way this is possible is to have the thumbnails stored in some local location rather than on the CD. This is the purpose of the local thumbnail option. With this option the thumbnails will be stored in a local user defined location (specified in View/Options) using a unique ID number instead of the image name (in case you have more than one image in the database with the same name). Now you can view the thumbnails of all your images whether or not they are currently mounted in a CD and only if you try to view the full size image will ImageDB complain if the image file is currently unmounted.

 

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