This information may prove interesting to the technically-minded user but it is not essential reading.
Under the hood, PMIO's thumbnails are complex beasts that require some explanation if advanced users are to get the best out of the fine control that PMIO offers.
Terminology
Recall that a thumbnail is the rectangular area on the thumbnail panel. Within that area is a small image called a thumb which is derived from your original image file.
Base thumbs
PMIO uses a two-pass thumb creation system. When it creates thumbs from your images, it first creates base thumbs for each image. These thumbs are stored in the database. Their appearance and quality is affected only by the advanced thumbnail preferences.
From the base thumbs, PMIO derives the thumbs that you see on the screen. It does this by resizing the base thumbs according to the settings in the Thumbnail Appearance window. Various other parts of the program show an ad-hoc thumb that is derived from the base thumb on the fly. The thumbs that appear on the rename dialog or the image properties dialog are examples of such thumbs. The Animation Window displays the raw base thumbs.
The Thumbnail Generation Process
Why the complexity?
This system was designed for speed and efficiency. The database only stores the base thumbs, thus saving disk space. The real thumbs are derived from the base thumbs on the fly as the thumbnail panel is painted onto the screen. They are then cached for increased drawing speed. The advantage is that you get immediate feedback when changing the thumbnail appearance. Previous versions of PMIO needed to 'reload the thumbnails' which involved resizing the source images all over again and was very slow.
- See also:
- About Thumbnails
The Animation Window
Thumbnail Panel
Image Properties
The Thumbnail Appearance Window
The Preferences Dialog
