This routine only works with ENVI Classic display groups and cannot be used with the ENVI display or in code that starts the application with the ENVI function.

Use this procedure to display a gray scale or RGB image in the current display group. You can optionally create a new display group. An interactive ENVI Classic session is required to run this procedure.

Syntax

ENVI_DISPLAY_BANDS, FID, POS [, IMAGE_OFFSET=array] [, IMAGE_SIZE=array] [, /NEW] [, /SCROLL_HIDE] [, SCROLL_OFFSET=array] [, SCROLL_REBIN=floating point] [, DYNAMIC_DISPLAY] [, WINDOW_STYLE={0 | 1 | 2 | 3}] [, ZOOM_FACTOR=integer] [, /ZOOM_HIDE] [, ZOOM_OFFSET=array] [, ZOOM_SIZE=array]

Arguments

FID

This is a one- or three-element array of long integers representing the file IDs of the files for each of the gray scale or RGB bands to display. When FID is a three-element array, the bands represent the red, green, and blue channels, respectively. All of the files listed in FID must have the same number of samples and lines.

POS

This is a one- or three-element array of long integers representing band positions. Elements of POS are paired with the elements of FID.

Keywords

IMAGE_OFFSET (optional)

Use this keyword to specify a two-element array of long integers representing the x and y offset in screen pixels, respectively, of the Image window.

IMAGE_SIZE (optional)

Use this keyword to specify a two-element array of long integers representing the x and y size in screen pixels, respectively, of the Image window.

NEW (optional)

Set this keyword to create a new display group. The default is to use the current display group. If no window exists, a new window is created.

SCROLL_REBIN (optional)

Use this keyword to specify the initial resize factor for the Scroll window. SCROLL_REBIN is a floating-point number greater than 1.0. The size of the Scroll window is determined as follows:

x = number of samples of input image / SCROLL_REBIN

y = number of lines of input image / SCROLL_REBIN

SCROLL_OFFSET (optional)

Use this keyword to specify a two-element array of long integers representing the x and y offset in screen pixels, respectively, of the Scroll window.

SCROLL_HIDE

Set this keyword to initially hide the Scroll window.

DYNAMIC_DISPLAY

Set this keyword to display the image in ENVI Classic. Use the /NEW keyword to clear the contents of the current display before displaying the image.

WINDOW_STYLE (optional)

Set this keyword to one of the following values to configure the style for new windows (created when you set the keyword NEW).

  • 0: Image/Scroll/Zoom
  • 1: Scroll/Zoom
  • 2: Image
  • 3: Zoom

The default is to use the window style specified in Preferences.

ZOOM_FACTOR (optional)

Use this keyword to specify the initial zoom factor for the Zoom window.

ZOOM_HIDE (optional)

Set this keyword to initially hide the Zoom window.

ZOOM_OFFSET (optional)

Use this keyword to specify a two-element array of long integers representing the x and y offset in screen pixels, respectively, of the Zoom window.

ZOOM_SIZE (optional)

Use this keyword to specify a two-element array of long integers representing the x and y size in screen pixels, respectively, of the Zoom window.

Example

The following code displays the first three bands of a file, specified by FID, as an RGB combination in a new display window.

envi_display_bands, [fid,fid,fid], [0,1,2], /new

API Version

4.2