USGS MIPS Vista Documentation

Vista Panels | Vista Menus | Dialog Buttons

This program allows visual examination and interrogation of digital images using the X Windows system. The optimal X display is a DirectColor device, however, Vista will function on TrueColor and PseudoColor devices. Also, Vista has the ability to launch other X applications which allow interactive editing, color coding, etc. of an image.

The first two topics, "Loading Black and White Images" and "Loading Color Images", are intended to quickly describe how to load an image in the viewing window. They do not cover any additional features of image loading.

Once an image is loaded the features of the stretch , zoom, roam, and blink panels can be utilized. The functions of these panels are described under the "Vista Control Panels" topic.

Other features of Vista, including loading features, are described in the "Vista Pull-Down Menus" topic. Additional features available from the pull-down menus include position and DN value interrogation.

Loading Black and White Images
In order to load a black and white image into the viewing window, use the mouse to select the "File" menu from the menubar. Then select "Open B/W" from the list of available items.

A dialog box will appear which asks for the name of the image to display. Enter the filename in the text field next to the B/W label and then press the Ok button.

The dialog box will disappear and the pointer will change to a watch while the image is being loaded. After the image is loaded the stretch, zoom, and roam panels can be utilized.

Loading Color Images
In order to load a color image into the viewing window, use the mouse to select the "File" menu from the menubar. Then select "Open RGB" from the list of available items.

A dialog box will appear which asks for the names of the three images to display. Enter the filenames in the text fields next to the red, green, and blue labels and then press the Ok button.

The dialog box will disappear and the pointer will change to a watch while the image is being loaded. After the image is loaded, the stretch, zoom, roam, and blink panels can be utilized.

Vista Control Panels

The panels on the left side of the window control the major features of Vista. They are available only if an image has been loaded into the viewing window. Even then, an option may not be available. If an option is not available a message will be given explaining why it is not (e.g. the X-window display does not support it).

For more information on the available control panels, click on the appropriate link below:

Stretch
Zoom
Roam
Blink

Stretch Panel

This panel is used to perform simple contrast stretches to an image. Additional control over the stretch panel is available by selecting the "Stretch" item from the Options Menu.

The stretch panel is not supported on TrueColor displays or for color images on PseudoColor displays.

Regional Stretch

This button applies a regional contrast stretch to the image. That is, it uses all the image data in the viewing window to determine the contrast stretch to apply. For information on how the contrast stretch is calculated see the section "Stretch Control Dialog".

If the viewing window is split into two halves the pointer will change to a question mark when the regional button is pressed. Select the half to contrast stretch by moving the pointer inside the desired half and then press mouse button one.

Local Stretch

This button applies a localized contrast stretch to the image. When the button is pressed the pointer will change to a question mark. Move the pointer to the desired location in the viewing window and press and hold down mouse button one.

A box will appear and change size as the mouse moves. Once the desired area is inside the box, release the button and a contrast stretch will be calculated based on the data inside the box.

For information on how the contrast stretch is calculated see the section "Stretch Control Dialog" topic.

Reset Stretch

This button resets a contrast stretch applied by the regional or local stretch buttons. That is, if the image is currently contrast stretched then this button will reset the image back to its original contrast.

Also, this button will reset a stretch created by a program launched from the applications menu (e.g., color slice or stretch).

Zoom Panel

This panel is used to redisplay the image currently loaded in the viewing window in a variety of ways. See descriptions of the individual buttons below. One feature common to most of the zoom buttons is a mark point.

To select a mark point move the pointer to the desired position inside the viewing window and press mouse button two. A cross will appear where the mark point was selected. The zoom buttons will use this point to perform their functions. If a mark point is not selected and a button is pressed then the center of the viewing window will be used as the mark point.

For additional information and control over the zoom panel see the "Zoom Control Dialog" topic.

In Button

This button will zoom in about the mark point by a zoom factor specified in the Zoom Control Dialog. The point that was marked will be zoomed to the center of the screen.

Out Button

This button will zoom out about the mark point by a zoom factor specified in the Zoom Control Dialog. The point that was marked will be zoomed to the center of the screen.

Center Button

This button will move the position under the mark point to the center of the screen while keeping the image at the same scale. Therefore, a mark point must be selected for this button to work.

Fill Button

This button will fill the viewing window with a compressed version of the entire image. This is equivalent to reloading the image using the Open B/W or Open RGB menu item.

This is the only zoom button that ignores the mark point.

1X Button

This button will move the position under the mark point to the center of the screen and set the scale so that each pixel in the image represents one pixel on the screen.

Roam Panel

This panel is used to roam/scroll through an image which is larger than the viewing window. All stretch and zoom information will be maintained during roaming.

For additional information and control over the roam panel see the "Roam Control Dialog" topic.

Roam Arrow Buttons

These arrow buttons cause the image to scroll so that image data can be seen in the direction of the arrow pressed. A single click of mouse button one on an arrow button will cause the image to move one time. A double click will cause the image to begin moving in that direction until the edge of the image is detected or the stop button is pressed.

Roam Stop Button

This button will cause the automatic roaming to stop.

Blink Panel

This panel is used to switch between images displaying one at a time(blinking between them). Blinking between two images where one image has been geometrically registered to another helps to visually detect any mis-registrations. For additional information and control over the blink panel see the "Blink Control Dialog" topic.

Blink Start Button

This button will start the automatic blinking of images.

Blink Stop Button

This button will cause the automatic blinking of images to stop.

Vista Pull-Down Menus

Pull-down menus provide ways for a user to select commands to execute. The following pull-down menus File, Options, Show, Applications and Help aid a user in displaying and interrogating images. To get information on a specific kind of pull-down menu, select one of the following links.

File
Options
Show
Applications
Help

File Menu

This menu gives access to the open black and white, open red, green and blue and open list dialogs along with the exit button for VISTA.

Open B/W Dialog

The open B/W dialog box is used to get the information to display a black and white image in the viewing window. This information includes the file specification, display area and the stretch parameters.

Input Text Field

This text field is used to enter the file specification of the image to be displayed. It also shows the file specification choosen when using the recall arrows or the file selection box.

File Selection Box

The select button is used to bring up a standard file selection box for choosing the image to be displayed. If a file is selected using the file selection box the file specification will be shown in the input text field.

Recalling Previous Files

The file selection arrow buttons are used to recall file specifications entered as input and output files for other MIPS programs. The up arrow will cause the most recent file specification to be shown in the input text field. Repeated activations of the up arrow will cause older files to be shown. The down arrow will show more recent file specifications.

Full and Split Modes

The display area radio buttons allows the image(s) to be displayed in one of the five areas. The Full option causes the entire viewing area to be used for the image. The Top and Bottom options cause the viewing area to be split horizontally , and the Left and Right options cause the viewing area to be split vertically; allowing two images to be viewed at once.

Stretch Mode

The stretch selection arrow buttons are used to recall stretches entered as input to other MIPS programs. The up arrow will cause the most recent stretch to be shown in the stretch text field. Repeated activations of the up arrow will cause older stretches to be shown. The down arrow will show more recent stretches.

Manual Stretch Text Field

This text field is used to enter the stretch to be applied to the image before it is loaded into the viewing window. It also shows the stretch choosen using the stretch recall arrows.

Recalling Manual Stretches

The stretch radio buttons allow the input image to have a stretch applied to the image before it is displayed in the viewing window. The "No Stretch" option will cause the image to be displayed with no stretch applied. The "Automatic stretch" option will cause vista to apply an automatic stretch to the image before it is displayed (see the Stretch Controle dialog for a discription of the algorithm used). The manual stretch option causes the stretch text field to be activated, allowing the user to type the desired stretch or use the arrow buttons to choose a stretch from the MIPS history.

Open RGB Dialog

The open RGB dialog box is used to get the information to display a color image in the viewing window. This information includes the file specification, display area and the stretch.

See Open B/W Dialog

Save Stretch

Selecting this item allows the user to save the stretches currently applied to the loaded image. Whether the image has been stretched or colorcoded, these stretches can be saved to a stretch file. Once saved, the stretches in the stretch file can then be applied to the image using the program Applystr or written out in another image format using the program Export.

Restore Stretch

Selecting this item allows Vista to restore the loaded image with its default stretch, which can be found in its stretch file(if it exists).

Exit

This option terminates Vista and any other programs that where launched from the applications menu.

Options Menu

This menu contains control dialogs which control features of the stretch, zoom, roam, and blink panels. This allows the user to customize these features to his/her preference.

Stretch Control Dialog

This dialog box allows the user to adjust parameters affecting the stretch panel buttons. These parameters also affect the automatic stretch option within the Open B/W and Open RGB dialogs.

Using the histogram obtained for the regional, local or automatic methods and the stretch parameters described in the topics below, a low and high DN are obtained and placed into the following stretch pairs to produce a nice contrast stretch:

0;0 low;0 high;255 255;255

Percentage Limits

The minimum and maximum percentages are used to find the low and high DNs in the histogram for the contrast stretch to be applied.

The default values are 0.5 and 99.5 for the percentages. Note, shifting the percentages closer to the middle of the histogram (e.g., 5 and 95) produces a harder contrast stretch while shifting them closer to 0 and 100 produces a softer stretch.

Valid Digital Numbers

The minimum and maximum valid DNs affect how the percentages are selected. DNs inside the range of minimum/maximum are used when determining the low and high DNs from the specified percentages. This is useful to prevent an image with a large number of zeroes (e.g., body of water) from adversely affecting the results of the stretch. The default values are 1 and 254, respectively.

Median Option

This option is used to modify the stretch from linear to piecewise-linear. The form of the linear stretch pairs is:

0;0 low;0 high;255 255;255

The form of the piecewise-linear stretch pairs is:

0;0 low;0 median;127 high;255 255;255

This means that the DN at 50% (median) would be mapped to 127.

K-Standard Deviations

This option is only used when loading 32-bit floating point images using the Open B/W or Open RGB dialogs.

A histogram can not be collected for a 32-bit image so instead the average and standard deviation of the image is used to determine the low and high DNs of the stretch pairs. The low is calculated by subtracting K standard deviations from the average and the high be adding K standard deviations to the average.

Zoom Control Dialog

This dialog box allows the zoom factor for the zoom panel in and out buttons to be adjusted to individual user preferences.

A value can be changed using the text field or the 1.5X, 2X, 3X, or 4X buttons, however, the new zoom factor will not be effective until the Ok or Apply button is pressed. A zoom factor entered on the text field does not have to be integral but must be greater than one and less than or equal to four.

Roam Control Dialog

This dialog box allows the roam delay and shift rates to be adjusted to individual preferences.

Roam Delay Rate

The delay scroll bar and input text box set the time delay between automatic roams. The scroll bar can be used to quickly set the delay or the text field can be used to set the delay from the keyboard. Legal values are from 0.0 to 5.0 seconds with a default value of 0.1 seconds.

Roam Movement Rate

The shift scroll bar and input text box set the number of pixels to scroll in the viewing window each time a roam occurs. The scroll bar can be used to quickly set the shift rate or the text field can be used to set the shift rate from the keyboard. Legal values are from 1 to 1024 pixels with a default value of 50 pixels.

Blink Control Dialog

This dialog box allows the blink parameters to be adjusted to individual preferences.

Manual Blinking

This radio button will select manual blinking as the current blink mode and deselect automatic blinking. In manual blink mode the user selects when a blink will occur. Each time the blink start button is pressed a new image will appear. Note, the label in the blink start button will change to "Next" the first time the start button is pressed.

Automatic Blinking

This radio button will select automatic blinking as the current blink mode and deselect manual blinking. In automatic blink mode, a blink will occur at a set time interval. To start blinking press the start button in the blink panel. The label of the start button will change to pause which stops blinking with the viewing window containing the currently blinked image. Press the resume button to continue blinking or the stop button to return to the original color image.

Automatic Blinking Rate

The blink rate text field and slider control the interval between blinks for the automatic blink mode. The default value is 1.0 seconds with valid values ranging from 0.1 to 5.0, inclusive.

Display Control Dialog

This dialog box allows the user to adjust the size of the viewing window. The number of lines and samples in the viewing window can be changed by entering new values in the text field, however, the display will not resize until the Ok or Apply button is pressed.

The values must be greater than one and any values greater than the size of the display will be set to the maximum size of the display.

Saving Control Settings

This option will save the current settings of the stretch, zoom, roam, blink, and display control dialogs. The settings will be stored in the file 'vista.dat' which will be located in the X windows user default directory (usually the home directory). The next time vista is executed these settings will be the default values for the control dialogs.

Restoring Control Settings

This option will restore the settings in the control dialogs to their default values. Recall that the default values are loaded from the file vista.dat(if it exists). Therefore, you must delete the file vista.dat in order to restore the true default values.

Show

This menu allows access to dialogs which give additional information about the displayed images and allow annotations, icons, vector and stretch information to be overlayed or applied to the images.

Show Position Information

This dialog box displays the line, sample, latitude, longitude and DN(s) of the image(s) under the pointer. If the pointer is not on an image, "n/a" is displayed for all fields. Similarly, if the image(s) do not contain projection labels the latitude and longitude will be "n/a".

Show Image Information

This dialog box displays the starting line, starting sample, ending line, ending sample and scale of the image(s) currently displayed.

Show Histogram Information

This dialog box displays the histogram of the the image(s) currently displayed.

Show Stretch Information

This dialog box displays pre and post stretches applied to the image(s) currently displayed.

Show Annotations Information

This option is not currently available.

Show Icons Information

This option is not currently available.

Show Vectors Information

This option is not currently available.

Applications

The applications menu allows the user to launch other X applications which allow interactive editing, color coding, etc. of an image. Note that before any application can be executed, an image must be loaded. For more information on a particular application, select on the appropriate link below.

H3>Help The help menu gives two options for obtaining help on this program.

Help On Context

When the On Context menu item is selected the pointer will change into a question mark. Move the question mark to the desired item and press mouse button one. This will give help on the item.

Help On Vista

When the On Vista menu item is selected a help dialog will appear with information about the capabilities of this program.

Help On Help

Besides utilizing "On context" or "On Vista", help can be obtained by moving the highlight to the desired item and pressing the Help or F1 key.

Dialog Buttons

When using Vista, the user may encounter a large number of dialog boxes. In these dialog boxes, the user may be asked to enter parameters, specify file names or even acknowledge a message. There are a number of buttons in these dialog boxes, each is explained below.

OK Button

The ok button is used to exit the dialog box.

Apply Button

The apply button is used to apply the current settings in the dialog box. Note, selecting this button does not exit the dialog box but allows the user to select options and view the results without having to bring this box up again.

Cancel Button

The cancel button is used to exit the dialog box without applying any of the parameters chosen.

Reset Button

The reset button is used to reset the parameters or options in the dialog box to their default settings.

Exit Button

The exit button is used to manually exit the dialog box.

Help Button

The help button is be used to obtain help on Vista.