You can get to advanced selection from the PRO menu, or by simply hitting the S key of the keyboard.:
When some filters work on an image (and they always work on the original image) they decide how to distribute the objects according to the characteristics of the image. By default you see the most objects or the most changes in the resulting image where the original image is brightest.
Note that not all filters are influenced so much by the original image. Some which are:
| • | Stardust |
| • | Snowflakes |
| • | Primitive Art |
| • | Pop Art |
You can change which parts of the original image receive most attention from the filter by hitting the ‘S’ key on the keyboard.
The rightmost slider is the edge & smoothing slider:
| • | When the slider is above the normal position this applies a smoothing effect to the force field, making changes from one region to another less abrupt. |
| • | When the slider is at the normal position no smoothing of the original image takes place. |
| • | When the slider is in the "edge" position, the effect will look for edges in the original image. And example would be in the StarDust effect. Setting this slider to "edge" will produce stars along the any obvious edges in the original image. |
The simulation of smoothing in the thumbnail image is only approximate.
Manipulating the other three sliders you can emphasize parts of the image and de-emphasize others. The main three sliders control Hue, Saturation and Value (the HSV color system).
| • | Hue: The base (rainbow) color of the color (e.g. red, blue, yellow, etc) . It is measured in degrees and goes from 0 to 360. |
| • | Saturation: The strength of the base color. |
| • | White black and grey all have zero saturation. |
| • | Pastel colors have medium saturation, |
| • | Strong (and primary) colors have maximum saturation) |
| • | Brown, dark green etc. have low saturation. |
| • | Value: The brightness of the color. |
| • | Black has zero value |
| • | White has maximim value |
| • | Pastel colors have high value |
The areas closest in color to that which you see in the rectangle above the slider are the areas which have most force for the effect. Here are some common settings:
| • | If all sliders apart from Value are at zero, then the force field looks like a black and white version of the orginal bitmap. This is the default and can be set with the Default button. |
| • | If the Saturation and Value are at maximum, then the Hue slider determines the force of the field. In this case you can choose Hue to select areas of a given color. In this way you can select green with the Hue slider and the parts of the image which a most similar to this green will have the most "importance" or "force" in the final image. |
You can mix and match all sliders to give you the force field you find most pleasing. If you get lost simply hit the default button.
The invert check box is for reversing the effect of the force field, so if, with the sliders, you chose highly saturated areas, clicking invert would give more force (white areas) to the unsaturated area. An example of the use of the invert check box is changing mountains into lakes and lakes into mountains with the Relief Map effect .
To use the invert check box you must go into manual mode (switch off the "Wizard chooses" check boxes in the effect you are interested in) .