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Technical Documents

ISIS 3 Application Documentation


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Display and analyze cubes

Overview Parameters


This program will display cubes and allow for interactive analysis. Although the program comprises a number of individual tools to perform analysis on your data, only the Spatial Plot Tool is discussed here until further notice.

Spatial Plot Tool

This tool is used for analyzing manually selected pixel DN values. It works with two different modes: linear and rotated rectangle. It is also capable of handling three different modes of interpolation: Nearest Neighbor, BiLinear and Cubic Convolution.


This mode involves drawing a line across an open cube. The selection is started by clicking and holding the mouse where you would like to start your calculations, at which point you may drag the mouse in any direction and release the click to establish the end of your selection.

The tool calculates the length of the line in pixels, rounding to the nearest full pixel value. It then divides the actual length of the line by this rounded length to achieve a step-size. Please note: This step size may be slightly bigger or smaller than a pixel length, but this difference becomes negligible for larger selections. For example, if the length of the drawn line was 2.91 pixels, the tool would round the length to 3 and the step-size would be 2.91/3 (or 0.97).

A plot window will be generated with the calculated DN values of the pixels. The first value to be calculated is the value where the original mouse click was made. At each increment, according to step size, the tool calculates the value along the line until it reaches where the mouse-click was released. This means that for a line with a rounded length of 3, the plot would show a total of 4 plotted DN values. Please note: For a line with a rounded length of n, the tool will calculate n + 1 values.

The images above include an example of the line as drawn in the cube view and the associated plot window. Marking has been added to delineate where mouse clicks were made and the DN values were calculated. The mouse was first clicked at dileneation marked "1" on the cube, and was released at "4". The number from the cube view correlates with the "Pixel Number" on the plot.

Rotated Rectangle

This mode of the Spatial Plot Tool involves drawing a rectangle across an open cube. The selection starts by clicking and holding the mouse where you would like to start your calculations, at which point you may drag the mouse in any direction and release the click to establish one edge of your selection. You may then drag the mouse away from this original line to expand in the other direction. A single mouse click establishes your final selection. Please note: The tool will lock angles to be perpendicular and so your selections will always be a perfect rectangle.

Similar to the linear mode of this tool, the lengths of the lines in pixels are rounded to the nearest full pixel value, and then the lengths are divided by their rounded lengths to establish a step-size. Please note: The step-size along one edge of the selection may differ from the step-size of the perpendicular edge, this becomes negligible for larger selections. For example, if the length of the line in one direction was 2.91 pixels, the step-size would be 2.91/3 (or 0.97), whereas if the length of the line in the perpendicular direction was 4.92, the step size would be 4.92/5 (0.98).

A plot window will be generated with the calculated DN values. This is done by calculating the value where the original mouse click was made, then continuing in the direction of that first-drawn line, calculating the DN value at each step-sized increment until it reaches where the original mouse-click was released. The tool will then calculate the average of these values. This average becomes the first value in the plot.

The tool will then shift a step-size along the perpendicular edge, and calculate the average DN value along a line running parallel to the first-drawn line. This average becomes the second value in the plot. The tool continues this pattern until it has reached the opposite edge of the rectangle as the first-drawn line.

The first image is the original selection. The second image is the same view that has been marked for reference purposes. Finally, the last image is the associated plot window. The original mouse click was made at delineation "1" within the cube view, the original mouse release was made at "5", and the final mouse click was made at "15". The Spatial Plot Tool calculates the average of the DN values at delineations 1-5, and this value is stored as "Pixel Value" 1 in the plot window, while the averages of 6-10 are stored in 2, and 7-15 are stored in 3.


Spatial Plot Tool makes use of Nearest Nieghbor, BiLinear and Cubic Convolution interpolations when calculating the DN values at particular points. Do be aware that when the tool is calculating a DN value at a particular point, it is calculating the interpolated DN value at that point.



Jeff Anderson2004-12-01 Original version
Jeff Anderson2006-01-06 Port to Qt4 and add blink tool
Elizabeth Miller2006-07-26 Fixed bug with filename expansion and added the MeasureTool
Brendan George2006-09-19 Documentation fixes
Steven Lambright2007-09-11 Added new rubber band functionality
Sharmila Prasad2009-10-19 Added Mosaic Tracking info like image index, serial number and file name in the Advanced Tracking window to have the ability to track mosaic origin.
Jeannie Walldren2010-03-08 Modified FindTool. If a user enters a line/sample in the Image tab, then the corresponding lat/lon is displayed in the Ground tab. Added Record button to FindTool to record clicked or typed point in the AdvancedTrackTool window.
Sharmila Prasad2010-03-19 "qview" now has the ability to handle exceptions. The status bar now displays a default NoWarning icon with "Ready" message. If an exception is caught, the icon changes to Warning and displays the error message. Clicking on the Warning icon will display a dialog window with the details of the most recent error occured. Closing the dialog or any other mouse activity will reset the Warning status.
Eric Hyer2010-03-22 Discontinued forcing of gui style to windows
Sharmila Prasad2010-03-24 Enable FindTool for images without camera and/or projection
Sharmila Prasad2011-02-16Added columns Local Emission and Incidence Angles for Advanced Tracking Tool
Sharmila Prasad2011-03-18 Connect the viewport's close signal to the all windows/subwindows like plottool and histogram tools as well.
Sharmila Prasad2011-05-11 Added options for SaveAs to save cube as fullImage, Export AsIs or Export FullResolution options
Steven Lambright, Jai Rideout and Tracie Sucharski2012-01-18 Re-implemented all of the plotting functionality in order to improve the user interface and capabilities. Added best fit lines and a scatter plot.
Steven Lambright2012-03-22 Added the sun shadow and feature nomenclature tools.
Tracie Sucharski2012-04-24 Added the stereo tool which calculates spot elevations and elevation profiles from pairs of stereo images.
Steven Lambright2012-05-29 Fixed prompts for saving edited files on closing so they are functional once again. Fixes #854.
Steven Lambright and Kimberly Oyama2012-06-11 Updated the nomenclature tool to include the option to choose from three types of extent displays (4 arrows, 8 arrows, or a box) and the option to display all features or only IAU approved features.
Kimberly Oyama and Steven Lambright2012-06-22 Updated the Advanced Track Tool to include a help menu and a help dialog that opesn with the tool and when the user opens it through the help menu. Fixes #772.
Kimberly Oyama and Steven Lambright2012-06-26 Fixed query range problems with the nomenclature tool. It can now handle longitudinal ranges that encompass the 0/360 line. Fixes #958.
Steven Lambright2012-06-28 The special pixel colorization tool's settings won't be forgotten when restretching. Also, images that are opened after using this tool will now take on the appropriate colors. Fixes #684.
Steven Lambright2012-06-29 Improved handling of special pixels in the statistics tool so that they are reported correctly. Fixes #199.
Steven Lambright2012-07-03 Added M/KM options to the spatial plot tool. Fixes #853.
Tracie Sucharski2012-07-30 Added the match tool which allows registration (control points) to be edited between cubes without a camera model.
Tracie Sucharski2012-10-01 Fixed bug in the match tool which caused qview to to print error messages and possibly crash when closing cube viewports either individually or from the File Menu.
Tracie Sucharski2013-01-08 Add the AlphaCube to the labels of and exported cropped cube. Fixes #706.
Tracie Sucharski2013-01-08 Fixed bug when saving a cube viewport that is displayed at full resolution, the application would seg fault. Fixes #1386.
Steven Lambright2013-01-24 Fixed spatial plot tool functionality on single line images. Fixes #997.
Steven Lambright2013-01-31 Improved upon the accuracy of the find tool's sync scale option. Fixes #953.
Steven Lambright2013-02-12 The red boxes that indicate the current selection (i.e. the rubber band) shown while creating plots, updating stretches, and other actions should now only draw on cubes (viewports) that are relevant to the action being performed. Fixes #1035.
Steven Lambright2013-02-07 The plot tables should no longer have multiple rows with the same X value. Also, fixed a crash related to closing the plot table windows. Fixes #710. Fixes #818.
Kimberly Oyama and Stuart Sices2013-12-30 Changed the character that is used as a token when parsing the list of file names used when the socket is already open. Fixes #1551.
Ian Humphrey2014-07-30 Modified spectral plot tool to more accurately compute statistics for rectangular and polygonal selections. Fixes #2071.
Ian Humphrey2014-07-31 Added configurePlotCurves() method to PlotWindow. User can activate configure dialog on single curve with right-click or activate dialog with combo box of all curves using the toolbar button. Added What's This for SpatialPlotTool and removed the configure toolbar button for ScatterPlotWindow. Fixes #2089.
Ian Humphrey2015-10-07 Updated icons. Fixes #1041.
Ian Humphrey2015-11-19 Added shortcuts to Match Tool window for selecting right measures, registration, undo registration, saving measures, saving the point, and saving the control network. Fixes #2324.
Ian Humphrey2017-05-10 Fixed initial loading of viewport and Fit to viewport zoom to correctly zoom to the center of the image. Fixes #4756.
Adam Paquette2017-05-19 Readded help menu for the 2D and 3D plot tools. Now properly display in both tools. Fixes #2126.
Summer Stapleton2018-03-14 Included documentation for Spatial Plot Tool in this .xml. References #5281.