# Getting around the user interface

The user interface includes components for navigation, adjusting filter settings, previewing the filter effect, and administering the plug-in. The basic layout of the interface is depicted in the following screenshot:

## The Preview Window

The Preview Window provides a real-time preview of the current filter settings. Each time you reposition the window or make a change to the filter settings, the corresponding region of the image is re-filtered and the result is displayed in the preview window.

You can zoom by clicking one of the magnifying-glass buttons on the right, or by using a mouse wheel. Magnification is limited to 100% or higher, in order to keep the filter calculation from taking too much time.

The View Original Pixels button displays the unfiltered image. The unfiltered pixels are displayed only while you hold the button down; when you release it, the filtered pixels are displayed.

The View Filter Mask button will display the filter mask created by the Noise Brush tool. The luminance mask is displayed in green, and the chroma mask is diplayed in red. Regions where both masks overlap are shown in intermediate colors (typically yellow).

The Hand Scroll tool allows you to drag the preview window to reposition it. You can also activate the Hand Scroll tool by pressing and holding the space bar on the keyboard.

The Noise Brush tool is used to modify the filter mask. Use this tool after you have made initial profile and filter adjustments. With the Noise Brush, you can protect regions of the image from filtering. Click here for more information about the Noise Brush.

## The Main Window and viewing controls

The Main Window displays the unfiltered image. It is used for navigating around the image and for profiling. The buttons beneath the window, described below, are used to control the magnification and other attributes of the window, and to activate various tools.

The Zoom buttons change the magnification of the window. They can increase magnification, decrease it, zoom to 100% magnification, or fit the entire image to the current window dimensions. If you have a mouse with a wheel, you can use the wheel to zoom in and out without having to click on the zoom buttons.

The Channel Selector allows you to display individual luminance or color channels for the image. This can make it easier to view noise that is associated with individual channels. Note that filtering applies to all channels regardless of the channel selector.

The Selection View combo box determines how the selection mask for the image is displayed. It has no effect on filtering. Also, it is deactivated if the image has no selection mask. (A selection mask is created using one of the host application's selection tools before invoking the Noise Ninja plug-in.)

The Hand Scroll tool allows you to drag the preview window to reposition it. You can also activate the Hand Scroll tool by pressing and holding the space bar on the keyboard.

The Navigation Tool is used to position the Preview Window within the image. It displays a green rectangle in the Main Window that indicates the current size and position of the Preview Window. You can drag the rectangle to change the position. Also, when you scroll or zoom the Preview Window, the rectangle is updated in the Main Window to reflect the new position and dimensions.

The Manual Profiling Tool is used to sample regions of the image to create a noise profile. To use the tool, select one or more regions. Each region should be uniform in tone and color, and it should not contain any meaningful detail.

## The Filter Controls

The filter controls are contained on several tabbed pages. There are controls for creating noise profiles, adjusting filter settings, controlling the Noise Brush, specifying policies to use in actions, viewing and editing profile annotations, and viewing image properties. These things are described in detail elsewhere.

## The Menu Bar

The menu bar at the top of the plug-in provides access to an assortment of administrative and other functions. Of particular interest is the Preferences dialog in the Noise Ninja menu; it can be used to configure several aspects of behavior in the plug-in.