GLIMSView Users GuideContents:
Introduction:
GLIMSView is a cross platform application intended to aid the process of glacier digitization for the GLIMS project. Specifically,
it allows the users to view various forms of satellite imagery, digitize glacier outlines within it, attach GLIMS specific
attributes to segments of these outlines, and export them to the ingest format described in the GLIMS documentation. An ingest
created with this tool is able to be directly inserted into a database of similar digitizations that can then be anylized for
scientific purposes. GLIMSView has been designed specifically for this functionality. Below are descriptions of methods to use
the application and produce ingests.
Installation:
As of the current version, v1.0, GLIMSView is not packaged with an installer. The binaries are available in a zipped folder and
contain everything needed to run. You can obtain the most recent release at http://www.glims.org. Download the file and
unzip it to wherever you prefer. Inside the unzipped folder will be an executable named “glimsview”, on Windows it
will be named “glimsview.exe”. To open GLIMSView, execute this file.
Create A Project:
With GLIMSView opened, the steps to create a new Project are:
If the image is loadable, GLIMSView will open the Band Selector.
Selecting Bands:
All bands available and compatible with GLIMSView will be displayed in the band selector. You can choose Greyscale for single band
display, or Color to display multiple bands in RGB. To assign a band a color, just select it in the list. When selecting a RGB
set, you choose the color that will be assigned to the next band selection with the color buttons by the Color radio button.
These are automatically cycled through as you select bands. When choosing a set of bands for RGB you must have a band selected for
every color. To load the bands into the views, press the Load Bands button.
Moving Around:
To zoom in and out use the zoom tools in GLIMSView's toolbar. Zooming can not be done on the Whole View. Choose a respective
zoom tool and press the left mouse button on one of the views. The view will be centered and zoomed on the pixel chosen.
To pan and move the displays select the Pan tool from GLIMSView's toolbar. Press and hold the left mouse button inside a red view
box and drag it to the desired position to change the view that is linked to it. For example, when changing the location of the
red view box in the Whole View, the location of the display in the Fixed view will change to that location.
To pan a view's display, press and hold the left mouse button within the view but not within its red view box and drag the image
to the new location.
Digitizing:
Creating Lines
To create glacier outlines choose the Line Tool in the GLIMSView's toolbar. When this tool is selected you can create lines in
all but the Whole View. To start a line, move the mouse over an editable view and press the left mouse button once. This will
leave a point that is the start of the line. Continue pressing with the left mouse button along the desired line to add points to
the line. To complete a line, press the right mouse button once. If you wish to have the beginning point and the end point
connected to form a polygon, hold the Control button down on the keyboard while pressing the right mouse button.
Creating Glacier IDs
To create GLIMS glacier id's choose the ID button in GLIMSView's toolbar. Move the mouse to the position where you want the ID
and press the left mouse button. A new glacier id will now be located there and in the Glacier ID list in the configuration
dialog.
Making Selection
To select points and lines choose the selection button in GLIMSView's toolbar. If you were previously using the line tool or the
glacier id tool, the selections made will affect those respectively. To make selections move the mouse to an editable view and
begin a selection box by pressing and holding the left mouse button. Drag the mouse to the desired dimensions and release to left
mouse button. All elements within the selection box will be selected. If the Glacier ID list in the configuration dialog is open,
the associated Glacier ID's will be highlighted in the list.
Deleting Points
To delete points, select them as described above and press the Delete key on your keyboard. If you delete all points for a line
the entire line will be removed from the dataset. This process is the same for deleting both points within lines and glacier ids.
Deleting Lines
To delete an entire line, select any portion of it. Then hold down the Control key and press the Delete key on you keyboard.
Joining Lines
To join to lines together, select two endpoints of two lines and press the Join Line button in GLIMSView's toolbar.
Breaking Lines
To break a line into two separate lines, select the point where you wish to break the line and press the Break Line button in
GLIMSView's toolbar. This will leave the point at which the line was broken in both resulting lines.
Continuing Lines and Inserting Points
When the Line tool is selected, the currently selected point will be the continuation point and the next point will come after it.
To continue a line from its end point, select the end point, choose the Line tool and continue adding points. To continue a line
from a non end point, select the point to continue from and continue adding points.
Moving Points
Select a line to make its nodes available. Then move the mouse to the point you wish to move. The cursor will turn to a cross
designating that you're over the point. Press the left mouse button to select that node only and drag the point. Release the
left mouse button where you want the point.
Undo
To revert to the previous state in the digitization, press both the Control and Z keys. This will undo selections, node
placements, and deletions.
Redo
To put back a state that was reverted using the Undo function, press the Control, Shift, and Z keys (or Control and Y keys).
This will restore selections, node placements, deletions, etc. that were changed by perforing an Undo. As soon as
a new action is taken (for example, placing or moving a node), the Redo history is cleared and Redo is no longer
available until the next time an Undo is performed.
*** Keyboard Tricks While Digitizing ***
To center the current display without switching to the Pan tool, just move the mouse over a view to the position you would like
the view centered on and press both the Control and C keys.
To add nodes to a line in reverse, hold the Control key down.
GLIMS Configuration Dialog:
This dialog is used to modify line properties, modify glacier id properties, modify the session data, and modify the image
acquisition date and time. To open the dialog choose Tools from GLIMSView's menu bar, then choose Open Config. The dialog will
popup. The different tabs let you select between the categories. Line Config
Line configurations are attribute sets that can be assigned to line segments in the views. A default set is provided when a new
project is created.
To create a new line configuration choose the New button, select the different attributes for the line and press Ok to add it to
the list.
To edit a line configuration, use the mouse to select it in the list, then press the Edit button. Modify the attributes and press
the Ok button.
The Import and Export buttons allows you to save and retrieve the list for different sessions. If you have created a list that
you want to use for different sessions, press the Export button. Use the file chooser that pops up to choose the file to save it
to. To retrieve a previously exported list, press the Import button. Use the file chooser that pops up to choose the exported
file.
Use the Change Line button to assign the currently selected line configuration to the selected lines within the views. First make
line selections with the selection process described above. Then select the line configuration to change the selections to. Then
press the Change Line button. Glacier Config
This allows you to view, create, modify, and assign glacier ids. To where a Glacier ID and its assoaciated lines are on the image, select a Glacier ID in the list. The Glacier ID point and associated lines will be highlighted in each of the views (if they are on the image).
To create a glacier id press the New Glacier ID button. Fill in the attributes and press the Add button. The new glacier id will
be available in the list. The preferred method for adding glacier ids is to use the glacier id tool and placing them on the views
as described above. If there is a known glacier id that is off the image and not accessible in the view, you can manually add one
this way.
To modify glacier ids, use the mouse to select a glacier id from the list, then press the Edit Glacier ID button. Modify its
attributes and press the Update button.
To assign glacier ids to line segments, select the line segments in the views and press the Set Lines button.
A dialog box with the list of Glacier IDs will open. Select the desired Glacier ID and click the Apply button. Session
Modifying any of the session parameters automatically updates the dataset that will be exported. Image Info
The acquisition date/time is currently the only modifiable attribute of the image for the GLIMS ingest. Changes to it
automatically update the dataset that will be exported.
Saving Projects:
There are two different formats to save a project as. One is the GLIMS ingest format described in the GLIMS documentation. This
populates a directory with shapefiles that hold all necessary data for a GLIMS ingest. The other format saves to a single XML
file containing all ingest information and information to return to the state the project was in when saved.
To export a GLIMSView project file choose Project from GLIMSView's menu bar. Then choose Save As which opens a file chooser.
Choose the file you wish to save it as.
To export a GLIMS ingest choose Project from GLIMSView's menu bar. Then choose Ingest which pops up a submenu. Then choose
Export. This opens a directory chooser. Select a directory that will be populated with a number of shapefiles that are in the
GLIMS ingest format.
Opening Projects:
To open a GLIMSView project file choose Project from GLIMSView's menu bar. Then choose Open. This pops up a file chooser where
you select the XML project file that was previously saved.
To open an GLIMS ingest choose Project from GLIMSView's menu bar. Then choose Ingest which pops up a submenu. Then choose Import.
This pops up a file chooser where you choose one of the shapefiles in the ingest. The shapefile naming conventions for GLIMSView
are any prefix, then either “session.shp”, “images.shp”, “glaciers.shp”, and “segments.shp”.
These shapefiles should have those names on the end of their filenames in order for GLIMSView to find them. GLIMSView will
attempt to locate the image that corresponds to the ingest with the shapefile data. If it can't you will be prompted to specify
the image associated with the chosen ingest. Choose the image with the file chooser that is provided.
Importing Generic Shapefiles:
When a generic shapefile is imported, its shape objects are added to the current project's vector dataset with default
configurations. This feature may produce unexpected results.
To import a generic shapefile choose Project from GLIMSView's menu bar. Then choose Import Shapefile. This pops up a file
chooser to select the shapefile.
The Image Menu:
The image menu in GLIMSView's menu bar contains options for changing the way the image is displayed.
The Histogram allows for contrast stretching. Open the histogram dialog and double click with the left mouse button on the
histogram display to add points to the piecewise linear contrast stretch. Use the menu items to change between different bands
and modify the points in the histogram display.
The Band Selector, as described above, allows band selection within the views.
The Memory Buffer toggle changes the buffering type. When the Memory Buffer menu item is toggled on, the entire image will be
loaded into memory which drastically speeds up image rendering on computers with large amounts of memory. Otherwise the image is
left on the hard drive and only the portions of the image displayed are stored within memory.
The Resample Method changes the resampling method to either bilinear or nearest neighbor.
Plugins:
Plugins allow third party software developers to create extensions to GLIMSView as share libraries. These are DLLs in windows and
Shared Objects in Unix.
Importing
Upon receiving a plugin file you must import it through GLIMSView in order to use it. To do this choose Tools from GLIMSView's
menu bar. Then choose Plugins which opens a submenu. Then choose Configure. This opens the Plugin Configuration dialog. Press
the Import button at the bottom which opens a file chooser. Choose the shared library file to be imported. If successful, the
plugin name will appear in the list of plugins. Otherwise you will receive an error message.
NOTE: Do not put the plugin in the $GLIMSVIEWPATH/plugins directory before importing. GLIMSView copies it to this directory for
its own use. Then you can dispose of the original file. Using Plugins
To obtain a plugin's description and usage details, open the plugin configurator and select it from the list. The description
will be displayed in the Description text area. To execute the plugin choose Tools from GLIMSView's menu bar. Then choose
Plugins which opens a sub menu. Then choose the plugin in the list. |