The 'Image location' configuration dialog provides controls for adjusting image scales and the 3D locations of the image data. It can be used to provide manual positions for data which does not have them by default, or to replace default values with manually-edited ones. It can also be used to show the image size and scales for data which already contains this information.
Once a data set has been loaded, there may be an initial button 'Change location and size' which allows you to manually edit the locations for an imported data set which already contains this information, for instance in DICOM or another 3D data format. All the following controls are disabled until this button is pressed, since in nearly all cases it is better to use the stored 3D locations. If you press this button, you will then be able to replace these with manually-edited ones.
Having replaced the stored locations, it is always possible to return to these values, simply by pressing the same button, which will now be labelled 'Reset to original values'. At that point, any manual changes you have made to these will be lost.
This section provides controls for manually estimating image locations. It is possible to create data sets where the image is translated along any of the three principal axes, and/or rotated about any of the three principal axes. As these controls change, the 3D visualisation windows update automatically, so you can see the effect that these positions and orientations have on the data.
The first comment indicates whether the current data has any locations, and whether these were manually created or not.
The following selection boxes and sliders allow the creation of these locations in a flexible manner for data which is not rectilinear (arranged regularly in a 3D grid).
Alternatively, setting a value in the 'frame spacing' box will seperate each frame of the loaded image data by this amount, to create a regular 3D data set. Note that the sign of this value determines in what z-direction each subsequent frame will be placed, and hence different signs will create either left-handed or right-handed versions of the 3D data. Many CT data sets have decreasing z-coordinates with increasing frame number and would hence have a negative frame spacing.
The first comment indicates whether any data is loaded, and, if so, what size each frame of this image data is.
The image scales can be set in either of two ways. The width and height of each frame can be explicitly set using the two sliders, in which case the scale (pixel size) in each direction does not have to be the same: this would generate non-square pixels.
Alternatively, setting a value in the 'pixel size' box will set the scale in both directions to be equal to this value.