2.6 Image Filters

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Functionality is available in the Pro edition
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PIC This function cannot be used for establishing a diagnosis

A filter is an algorithm for transforming series images with various effects in the image viewer window. The DICOM Viewer provides filters for blurring images, changing sharpness and reducing visual noise.

Filters for image processing are available in the Image Viewer, MPR reconstruction, Vessel analysis and Coronary artery analysis tabs.

2.6.1 Preset Filters

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Functionality is available in the Pro edition
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PIC This function cannot be used for establishing a diagnosis

To choose and apply a preset filter in the Image Viewer tab, on the main menu, select Image->Filters and from the filter list, select the desired filter.

You can choose preset filters with the following parameters:

In the Image Viewer tab, the filter is applied to the selected window. If you select a series window, the filter is applied to the whole series. If you choose a study window, it is applied to all the series of the study.

Only one filter may be applied to a selected series window. The current filter is highlighted with blue on the list of filters, and marked with a flag. The name of the filter is shown in the left-hand bottom corner of the window for which the filter is used.

If you apply a filter to an image, you will see an asterisk "*" symbol in the ROI measurement results and intensity value line. It informs the user that the measurement results are affected by the filter applied.

PIC An image to which a filter has been applied is not original, and the measurement results may be inaccurate.

Preset filters are switched cyclically (see Section 2.6.3).

After the window is closed, the preset filter is reset and is not applied when the window is opened again.

2.6.2 User Filters

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Functionality is available in the Pro edition
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PIC This function cannot be used for establishing a diagnosis

The DICOM Viewer provides an opportunity to apply customized user filters. There are three user filters on the main menu of the program:

To set the parameters and apply a user filter, check one of the user filters on the list of filters of the main menu.

In the dialog box that pops up, set the following parameters:

Fig. 2.8 shows the dialog box for customizing the Sharpen user filter.


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Figure 2.8: Dialog box for customizing the Sharpen user filter


There are several ways to set the values of parameters in the dialog box for user filters:

When parameters are changed in the dialog box for user filters, the changes are simultaneously reflected in the viewer window. When the dialog box is closed, the current user filter is not reset.

The values of the parameters are saved and applied next time you select the user filter.

2.6.3 Actions with Filters

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Functionality is available in the Pro edition
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PIC This function cannot be used for establishing a diagnosis

There are several ways to activate a filter:

To go to the next or previous filter, proceed as follows:

Preset filters are switched cyclically. After the last preset filter on the list you go to the first one. You do not switch to user filters.

There are several ways to reset the current filter:

You can assign a hotkey to each filter (see Section 16.8).