Thumbnail window

This window lets you customize gallery thumbnails - small images representing full-size images. You can specify thumbnail size, image quality, apply various effects and create rollover thumbnails.

The thumbnail window is an entirely visual tool. Gena shows you exactly the same picture as you will see in the index page after the gallery creation. (Strictly speaking, the previous statement is true if you enable jpeg preview mode. Otherwise you'll see your thumbnail with the correct size and with all effects applied but without the jpeg compression artifacts).

Thumbnail size control

specifies thumbnail dimensions.
Note, that you are specifying width and height not only for the picture you are viewing in the window, but for all thumbnails in the gallery. The "Width" and "Height" boxes actually specify maximum image width and height and Resize method box tells Gena whether to use specific value or not.

The application support several resize modes: (see also examples below)

Note, that Fixed Width, Fixed Height and Best Fit modes can produce thumbnails with different sizes. Usually index pages look better when all thumbnails are exactly same size and you can choose between Best Fit with Fill and Crop modes to provide this appearance.

The "Crop"mode usually produces better-looking index pages, but an obvious drawback is that the thumbnail shows only a part of the full-size image. For normal digital photos with 4:3 and 3:4 aspect ratios, the gallery usually looks OK in this mode with square or 4:3 thumbnails. If some pictures are really "wide" and some others are really "tall", then the "Crop" mode will show too small part of the full-size picture, which may be unacceptable.

The following question is quite appropriate here. What if you don't want the center part of a particular image to be cropped? Gena has a solution in this case too! While hovering above a thumbnail image you can see the mouse pointer changes to look like a hand with horizontal or vertical arrows. If the aspect ratio of the specified dimensions doesn't match the aspect ratio of some picture, it means that only one dimension will be changed while the other will remain unchanged. The arrows on the hand-pointer just show in which direction the cropping area for the current image can be changed. To actually change cropping area, click the left mouse button (the mouse pointer will change to a fist) and drag the picture while you're dragging the mouse. When dragging the image, press Esc or click the right mouse button to cancel the current action. Note, any changes affecting the thumbnail dimensions ("width", "height", "crop" boxes) reset all cropping areas of all thumbnails to a center position.


Here is an example. Suppose we have two full-size pictures, one has landscape orientation 160x120, another has portrait orientation 120x160:

Pic1, 160x120 Pic2, 120x160


1. In the Fixed Width mode let's set the thumbnail Width to 100. Gena will produce two thumbnails, 100x75 and 100x133. (So both images will have width 100):

100x75 100x133


2. Now let's set the mode to Fixed Height and set the Height to 100. Gena will produce two thumbnails, 133x100 and 75x100. (So both images will have height 100):

133x100 75x100


3. In the Best Fit Mode with Width x Height set to 100x100 Gena will produce two thumbnails, 100x75 and 75x100. The "Landscape" picture will have width 100, and the "portrait" picture will have height 100.

100x75 75x100


4. In the Best Fit with Fill Mode with Width x Height set to 100x100 Gena will produce two thumbnails 100x100. Note, that pictures themselves are resized to 100x75 and 75x100 and extended to 100x100 using fill color (border color).

100x75 75x100


5. Let's set the Crop mode, with Width and Height again set to 100. Gena will make 100x100 thumbnails for both pictures. Note, that on the first picture parts of the shore on the right and on the left are missing. Right picture doesn't display full sky and lower part. But this "index" actually looks better, right ?

100x100 100x100


Normal/Highlight switch

lets you preview normal thumbnail or highlighted ("MouseOver") thumbnail. When you switch this mode Gena shows the effects settings for normal/highlighted thumbnails respectively.


JPEG quality control

This control lets the user specify jpeg quality for thumbnails. The quality is measured from 0 to 100, 0 - the lowest quality and the smallest file size, 100 - the best quality and the largest file size. We recommend that you use values between 50 and 70 for typical photographic images without thin borders and values between 70 and 90 for graphic pictures and pictures with a thin border. (We suggest that you use better quality in latter case because the JPEG compression algorithm is optimized for continuous-tone pictures and can introduce annoying artifacts on sharp artificial contours). Anyway, you can always evaluate resulting image quality by switching to JPEG preview mode (just check the "preview" box). In preview mode you can also see jpeg file size in bytes. So you can always find the best balance between thumbnail file size and image quality.

The Presets button displays the Presets dialog


Thumbnail Effects

Thumbnail effects are actually a set of simple image filters. A sequence of filters is applied to resized source image to produce the resulting thumbnail. You can enable/disable each filter (effect) and adjust parameters of individual filters.

Shadow - Draws shadow "behind" the thumbnail. You can specify shadow shift (i.e. size of shadow) and blur - sharpness of the border between the shadow and a background.
Here is an example:

Shift 0, Blur 0 Shift 7, Blur 0 Shift 7, Blur 5.0


Border - Draws rounded or rectangular border around the thumbnail. You can adjust border width, color and radius for rounded corners. Radius value gradually changes the shape of the border from rectangle to ellipse. Maximum radius value for square thumbnails produces a nice circle.
Some examples again:

Border 3, Radius 0 Border 3, Radius 25 Border 3, Radius 200 Border 15, Radius 15



Light - Changes image Brightness and Contrast.

Bright 0, Contrast 0 Bright 0, Contrast 5.0 Bright 50, Contrast 0


Mono - Convert the image to monochromatic (one color) with specified hue value. Using this effect you can make black-and-white pictures, sepia pictures, etc.

Hue 0 Hue 4 Hue 41


The Background color button selects a thumbnail background color. (See also this information about the separate table color option in Advanced Settings and how it affects Index page background).


Rollover effects settings

(See also general information about Rollover Thumbnails in Gena here)

This section allows you to specify how highlighted thumbnail effects will differ from normal thumbnail effects. Note, that Gena doesn't allow user to adjust Shadow and Border parameters separately for highlighted and normal thumbnails because these effects change the actual size of the thumbnail. Rollover images with different sizes look really ugly, so normal and highlighted thumbnails always share the same shadow/border parameters.

The Effects settings pane has two parts, effects from upper part (Background Color, Shadow and Border) are "shared" between normal and highlighted thumbnails. Effects from the lower part (Border Color, Light, Mono) can be set separately. When the thumbnail type selection tab is in the "Normal" position, you can see and change the settings for normal thumbnails, when the tab is in the "Highlight" position you change the settings for highlighted thumbnails. In the "Highlight" mode you can also reset all highlight effects settings to the "normal" set of settings using the "As Normal" button. (In that case normal/highlighted thumbnails will be the same and you can start adjusting highlight effects to create rollover "from scratch").

The Rollover mode checkbox enables usage of the rollover thumbnails in general. If this checkbox is cleared you can't preview highlight effects or adjust settings of highlight effects.



The Presets dialog allows you to save and load thumbnail effects. So you can create a nice-looking effect for one gallery and reuse it later for pictures in another gallery. You can also reuse the thumbnail settings only partially - e.g. effects without modifying image size, with or without color change etc.

List of available presets located in the right pane of the Presets window. You can select standard effects (supplied with Gena) and custom effects (created by you). When you click on the preset name you can see how normal and dynamic thumbnails look like with this preset. (The Preset preview window displays a picture created when this specific preset was saved). To load selected preset from the file click the "Load" button. You can specify what part of the preset to load by setting or clearing the following checkboxes : Highlight effects, Dimensions, Background color and Border color. (the Dimensions checkbox responsible for entire Thumbnail size control, if this checkbox is cleared thumbnail size will not be modified). If all checkboxes are cleared, Gena will load only normal effects without modifying thumbnail size and colors.

To save current thumbnail effects as a new preset, type preset name and click the "Save Current" button.

The "Delete" button deletes selected preset. (Presets with "+" sign are read-only, you can't delete them from this dialog).