About Thumbnails

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In PMIO, a thumbnail is a rectangular area of the browser which contains, among other things, a small picture (a thumb) representing an image file on disk. As far as PMIO is concerned, the thumbnail is the image. This means that if you move or delete a thumbnail, you’re actually moving or deleting the image file too. This is the same as in Windows Explorer, where an icon represents a file. Thumbnails typically show scaled down versions of the images, but they can also just display textual information. When you first navigate to a location, the program scans it and finds all image files that it recognises. It then creates a thumbnail for each image file, and begins to load the files and create scaled down versions of them. At this time, the image is also entered in the catalogue for future reference.

As each image is loaded, its thumbnail changes from a text-only display to the actual scaled down image. Various preferences affect the new thumbnails, for example thumbnail dimensions and quality. The dimensions refer to the size of the thumbnail imagery. You can create thumbnail imagery ranging in size from 16x16 pixels to 400x400 pixels. Generally, it is a good idea to create smaller thumbnails when the folder has a lot of images in it. This keeps the memory usage to a minimum. The thumbnail imagery is internally stored as JPEG data. Because of this, the JPEG quality preference affects thumbnail quality.

Once created, the thumbs are stored in a database on disk which allows them to be quickly loaded next time they are needed, instead of having to load each original image and scale it down again. Note: The database in later versions of PMIO replaces the browse files that were used in earlier versions.

The Web Page Wizard can be used to save the thumbnail imagery to disk as ordinary JPEG files with associated HTML documents (web pages).

Thumbnail Components

Each thumbnail is composed of various components which give information or provide functionality.

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Thumbnail Components

Memo Button

These buttons display the image properties dialog allowing you to edit the Standard and HTML memos of the underlying image.

Rotation Indicator

This indicator, if present in the lower left corner, shows that the thumbnail has been rotated and by how much.

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Rotation Indicator

Label

The thumbnail label is a line of text which, by default, shows the file name (sans extension) of the underlying image. You can change the text in the Thumbnail Appearance Window.

Imagery

The thumbnail imagery shows a scaled down version of the underlying image. The method by which this imagery is created is complex and has many options which can be changed in the Thumbnail Appearance Window.

Hot Tracking

When the mouse pointer passes over a thumbnail, the thumbnail is highlighted and the memo indicators appear. This gives you some extra visual feedback.

Size Cue

A small rectangle in the lower right corner gives a cue about the size of the underlying images. The diagram below explains how this indicator works.

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Thumbnail Size Cue

For an advanced discussion of the thumbnail generation process, please see the technical details page.

See also:
The Database

The Catalogue

Preferences - JPEG page

Creating a Web Page

About Memos

Rotating Thumbnails

The Thumbnail Appearance Window

Thumbnails - Technical Details