wxDicom

Menus, mouse input and layout

Layout

wxDicom has one main window on the left which displays the current image, and a region on the right containing the various controls, with a status bar underneath. The controls are mostly collected in tabbed pages. Underneath these is the frame slider: if an image is loaded which is a part of a numerical sequence in the same directory, then this slider can be used to select other images in this sequence.

There are also some overlays (drawn on top of the current image) which can appear at different times, and can also be disabled completely using the 'Display Overlay' menu option described below. During 'windowing' a graph is drawn top-left to show what the current mapping between image and display pixels is. If a line is defined (see 'Mouse input' below) a graph is drawn top-right which displays how the image data varies along this line. The current mask can also be displayed at the bottom left.

Menus

File

Open: Open a file in various different image and machine-specific formats, including DICOM.
Open reference: Open a reference image, used to compare with the current image and calculate noise reduction.
Close: wxDicom can only have one file (except for the reference) open at any time.
Save interpolated: This will save the image, with the current processing, zoom and display settings, and display size, to a chosen image format.
Save processed: This will save the image, with the current processing but not interpolated and with the original size, to a chosen image format.
Save sequence: This will save the whole sequence (if there is one) to a new set of images, applying the current processing to each as it does so.
Process DICOM/TIFF: This will save a new DICOM or TIFF sequence (if the original data was in this format) in a sub-folder, with the current processing applied to it.
Exit: Exit wxDicom, with no prompt about saving data.

Display

Zoom to fit: This makes the current image as large as possible whilst ensuring you can see all of it, and keeping the original aspect ratio.
Unity zoom: This ensures that the image pixels are the same size as the screen pixels, so no interpolation is required.
Resize to image: This makes the wxDicom viewing area exactly the same size (same number of pixels) as the image.
Reset windowing: This returns the 'windowing' (the mapping between image data values and actual displayed brightness) to the default for this image.
Display overlay: This either shows or hides the various overlays (see description above) in the main image window.
Overlay font: This changes the text font and text size used for the various overlays.

Help

Help window: Shows this help window.
Online pages: Starts up an external browser with the online web pages for wxDicom.
Check for updates: Checks whether there are any more recent versions of wxDicom and shows the new version history.
About...: Information about the software and author.

Mouse input

Left click: A left click without moving will zoom out from the current view. A left click and drag will draw a rectangle on the screen: releasing the mouse will then zoom in as much as possible whilst displaying everything in this rectangle.
Middle click: This can be used to reposition the image on the screen without changing the level of zoom.
Right click: A right click changes the 'windowing', or the mapping between image values and display values. This is a common operation for medical data. Right clicking and dragging left and right will change the brightness of the displayed image, whilst right clicking and dragging up and down will change the contrast. You can use the 'Reset Windowing' menu option to return everything to default values.
Shift-left click: Holding the shift key down whilst clicking and dragging can be used to define a line in the image, which is used either to display the data along this line, or to affect some of the other processing operations. Holding the shift key down and clicking without dragging removes the current line.
Shift/Ctrl-right click: Shift-right click will display the (forward) mask which is currently in use at the pixel at the mouse location. A ctrl-right click will display the inverse mask, if there is one, i.e. for an opening or closing operation, or a combination.
Scroll wheel: This zooms in and out, keeping the centre of the displayed image at the same location.

Each time the level of zoom is changed, the current zoom factor, image and display sizes are shown in the status bar at the bottom centre. In addition, moving the mouse to any point on the displayed image will show the RGB values at this pixel in the status bar at the bottom right.

Key presses

Some aspects of wxDicom can be controlled with key presses:

Space bar: Toggles display of the overlay.
H or h: Toggles display of a histogram of the current image, so long as the overlay is displayed.
N or n: Compares the current image to the reference, if loaded.
S or s: Toggles between use of sorting or histograms in morphological operators.
Q or q: Quits wxDicom.