XImtool On-Line Help Summary

Welcome to XImtool V1.1

XImtool is an image display server developed by the IRAF Project at the National Optical Astronomy Observatories. To view images you need client software (such as IRAF) to load images into the display, or it can load images directly when run as a standalone task. XImtool is interchangeable with older display servers such as SAOimage / IMTOOL and with newer servers like SAOtng, but offers many new features not available elsewhere.

More detailed help is available on the following topics:

Basic Usage:

Advanced Features:

        Getting Started
        GUI Overview
        Mouse Operations
        Keystroke Accelerators
        Command-line Options
        Client Connections
	Frame Buffers
        Markers
            Panner Marker
            Coords Box Marker
            General Markers
                Menu Options
        Control Panel
            View Controls
            Enhancement Controls
            Blink Controls
            Options:
                Autoscale
                Antialiasing
                Tile Frames
                Warnings
	Colormap Selection
                Builtin Colormaps
                User-defined Colormaps
        Load Panel
            Directory browsing
            File Patterns
            Direct File Load
            Frame Selections
        Save Panel
            File Name
            Format
            Color
        Print Panel
            Postscript Options
            Color Options
            Processing Options
            Printer selection
        Info Panel
        TclShell

Getting Started

As a display server, XImtool is started as a separate process from client software such as IRAF. Once it is running it will accept client connections simultaneously on fifo pipes, unix domain sockets, or inet sockets. A display client like the IRAF DISPLAY task makes a connection and sends the image across using an IIS protocol (other/different protocols may be supported in the future). Once the image is loaded in the display buffer it may be enhanced, saved to a disk file in a number of different formats, or printed as Encapsulated Postscript to a printer or disk file.

When run in standalone mode, images may be loaded on the command line or by using the Load Panel. This allows you to browse images and perform the same manipulations as if they had been displayed by a client.

GUI Overview

The GUI consists of a large image display window and a number of smaller panels that control various specific functions such as image Load, Save and Print as well as a general purpose Control Panel. The main window menubar has several menu buttons to the left: the Files menu is used to load/save/print an image as well as quit the task. The View menu let's you select the image orientation, zoom, colormap or frame. The Options menu allows you to call up control panels, toggle markers or blinking etc. Some of this functionality is duplicated elsewhere in the GUI. The right side of the menubar contains command buttons to flip the image as well as buttons for frame selection and the help button.

For more detailed information on the operation of the control panels please see the on-line help (i.e. use the '?' button or Alt-h keystroke in the main image window).

Mouse Operations

Clicking and dragging MB1 (mouse button 1) in the main image window creates a rectangular region marker, used to select a region of the image. If you do this accidentally and don't want the marker, put the pointer in the marker and type DELETE or BACKSPACE to delete the marker. With the pointer in the marker, MB3 will call up a marker menu listing some things you can do with the marker, like zoom the outlined region. MB1 can be used to drag or resize the marker. See below for more information on markers.

Clicking on MB2 in the main image window pans (one click) or zooms (two clicks) the image. Further clicks cycle through the builtin zoom factors. Moving the pointer to a new location and clicking moves the feature under the pointer to the center of the display window. Holding down the Shift key while clicking MB2 will cause a full-screen crosshair cursor to appear until the button is released, this can be useful for fine positioning of the cursor.

MB3 is used to adjust the contrast and brightness of the displayed image. The position of the pointer within the display window determines the contrast and brightness values. Click once to set the values corresponding to the pointer location, or click and drag to continuously adjust the display.

Keystroke Accelerators

The following keystrokes are currently defined in the GUI:

  
Ctrl-b   Backward frame        Alt-b  Blink frames (toggle)
Ctrl-c   Center frame?         Alt-c  Control panel
Ctrl-f   Forward frame         Alt-h  Help
Ctrl-i   Invert?               Alt-i  Info box popup
Ctrl-m   Match LUTs            Alt-l  Load file popup
Ctrl-n   Normalize             Alt-p  Print popup
Ctrl-p   Print                 Alt-s  Save popup
Ctrl-r   Register              Alt-t  TclShell popup
Ctrl-t   Tile frames toggle
Ctrl-u   Unzoom (zoom=1)
Ctrl-x   Flip X       	       Ctrl-Alt-q  Quit
Ctrl-y   Flip Y       	       Ctrl-Alt-f  Fitframe

Ctrl-=   Print
Ctrl-<   Decrease blink rate   Ctrl-+   Zoom in
Ctrl->   Increase blink rate   Ctrl--   Zoom out
   
Alt-1 thru Alt-4      Set frame displayed
Ctrl-1 thru Ctrl-9    Set integer zoom factor

NOTE: These keystrokes only work with the cursor in the main image window, not on the subwindows or in markers.

Client Connections

Ximtool allows clients to connect in any of the following ways:

fifo pipes

The traditional approach. The default, global /dev/imt1[io] pipes may be used, or a private set of fifos.

tcp/ip socket

Clients connect via a tcp/ip socket. There is a default port, or a custom port may be specified. This permits connecting to the server over a remote network connection anywhere on the Internet.

unix domain socket

Like a tcp/ip socket, but limited to a single host system. Usually faster than a tcp/ip socket, and comparable to a fifo. By default each user gets their own unix domain socket, so this option allows multiple users to run ximtools on the same host without having to customize things.

By default ximtool listens simultaneously for client connctions on all three types of ports. Clients communicate with XImtool using the IIS protocol, other protocols may be supported in the future.

Frame Buffers

XImtool starts up using default frame buffer of 512x512 pixels. When loading disk images the frame buffer configuration file will be searched for a defined frame buffer that is the same size or larger than the current image, when used as a display server the frame buffer configuration number is passed in by the client. The default file used is /usr/local/lib/imtoolrc, this can be overridden by defining a IMTOOLRC environment variable naming the file to be used, or by creating a .imtoolrc file in your home directory.

The format of the frame buffer configuration file is

   configno nframes width height [extra fields]
e.g.                   
	1  2  512  512
	2  2  800  800
	3  1 1024 1024          # comment

At most 128 frame buffer sizes may be defined.

Command-line Options

The following command-line options are currently recognized:

  -basePixel < num >       Base colormap pixel number
  -cmap1 < file >          User cmap 1 
  -cmap2 < file >          User cmap 2 
  -cmapDir1 < dir >        User cmapDir 1 
  -cmapDir1 < dir >        User cmapDir 2 
  -cmapInitialize < bool > Initialize colormap at startup
  -cmapName < name >       Private colormap name 
  -config < num >          Initial config number
  -defgui                  Print default GUI to stdout
  -displayPanner < bool >  Display panner box
  -displayCoords < bool >  Display wcs coords box
  -fifo < pipe >           Fifo pipe to use
  -fifo_only               Use fifo pipes only 
  -gui < file >            GUI file to use 
  -help                    Print command-line summary 
  -imtoolrc < file >       Frame buffer configuration file 
  -inet_only               Use inet sockets only 
  -invert                  Invert colormap on startup?
  -maxColors < num >       Number of colors 
  -memModel < type >       Memory model (fast,small,beNiceToServer)
  -nframes < num >         Number of frames at startup
  -port < num >            Inet port to use
  -printConfig < file >    Printer configuration file 
  -port_only               Use inet sockets only 
  -tile                    Tile frames on startup?
  -unix < name >           Unix socket to use
  -unix_only               Use unix sockets only 
  < file >                 File to load on startup

Markers

Panner Marker

The panner window always displays the full frame buffer. Try setting the frame buffer configuration to a nonsquare frame buffer (e.g. imtcryo) and then displaying a square image (e.g. dev$pix) and the panner will show you exactly where the image has been loaded into the frame.

The panner window uses two markers, one for the window border and one to mark the displayed region of the frame. Most of the usual marker keystrokes mentioned below apply to these markers as well, e.g. you can use MB1 to reposition on the panner window within the main image display window, or to drag the region marker within the panner (pan the image). Resizing the region marker zooms the image; this is a non-aspect constrained zoom. The panner window itself can be resized by dragging a corner with MB1. Typing delete or backspace anywhere in the panner window deletes the panner.

A special case is MB2. Hitting MB2 anywhere in the panner window pans the image to that point. This is analogous to typing MB2 in the main display window to pan the image.

Coords Box Marker

Ximtool provides a limited notion of world coordinates, allowing frame buffer pixel coordinates and pixel values to be converted to some arbitrary client defined coordinate system. The coords box feature is used to display these world coordinates as the pointer is moved about in the image window.

The quantities displayed in the coords box are X, Y, and Z: the X,Y world coordinates of the pointer, and Z, the world equivalent of the pixel value under the pointer. All coordinate systems are linear. The precision of a displayed quantity is limited by the range of values of the associated raw frame buffer value. For example, if the display window is 512x512 only 512 coordinate values are possible in either axis (the positional precision can be increased however by zooming the image). More seriously, at most about 200 pixel values can be displayed since this is the limit on the range of pixel values loaded into the frame buffer. If a display pixel is saturated a "+" will be displayed after the intensity value.

The coords box is a marker (text marker) and it can be moved and resized with the pointer like any other marker.

General Markers

Although ximtool doesn't do much with markers currently, they are a general feature of the Gterm widget and are used more extensively in other programs (e.g. the prototype IRAF science GUI applications). Ximtool uses markers for the marker zoom feature discussed above, and also for the panner and the coords box. All markers share some of the same characteristics, so it is worthwhile learning basic marker manipulation keystrokes.

MB1 anywhere inside a marker may be used to drag the marker.
MB1 near a marker corner or edge, depending on the type of marker, resizes the marker.
Shift-MB1 on the corner of most markers will rotate the marker.
Markers stack, if you have several markers and you put one on top of the other. The active marker is highlighted to tell you which of the stacked markers is active. If the markers overlap, this will be marker "on top" in the stacking order.
MB2 in the body of a marker "lowers" the marker, i.e. moves it to the bottom of the stacking order.
Delete or backspace in a marker deletes it.
Markers have their own translation resources and so the default keystroke commands will not be recognized when the cursor is in a marker.

For example, try placing the pointer anywhere in the coords box, then press MB1 and hold it down, and drag the coords box marker somewhere else on the screen. You can also resize the coords box by dragging a corner, or delete it with the delete or backspace key. (The Initialize button will get the original coords box back if you delete it).

Marker Menu Options

MB3 (mouse button 3) calls up the marker menu (by default).
Zoom does an equal aspect zoom of the region outlined by the marker. In this way you can mark a region of the image and zoom it up.
Fill exactly zooms the area outlined by the marker, making it fill the display window. Since the marker is not likely to be exactly square, the aspect ratio of the resultant image will not be unitary.
Print prints the region outlined by the marker to the printer or file currently configured by the Print Panel.
Save saves the region outlined by the marker to the file currently configured by the Save Panel.
Info prints a description of the marked region. The text is printed in the Info Panel.
Unrotate unrotates a rotated marker.
Color is a menu of possible marker colors.
Type is a menu of possible marker types. This is still a little buggy and it isn't very useful, but you can use it to play with different types of markers.
Destroy destroys the marker. You can also hit the delete or backspace key in a marker to destroy the marker.

Control Panel

View Controls

The Frame box will list only the frame buffers you currently have defined. Currently, the only way to destroy a frame buffer is to change the frame buffer configuration, new frame buffers (up to 4) will be created automatically if requested by the client.

The text display window gives the field X,Y center, X,Y scale factors, and the X,Y zoom factors. The scale factor and the zoom factor will be the same unless autoscale is enabled. The scale is in units of display pixels per frame buffer pixel, and is an absolute measure (it doesn't matter whether or not autoscale is enabled). Zoom is relative to the autoscale factor, which is 1.0 if autoscaling is disabled. This information is also presented in the Info panel.

The numbers in the Zoom box are zoom factors. Blue numbers zoom, red numbers dezoom. Zoom In and Zoom Out may be used to go to larger or smaller zoom factors, e.g. "Ctrl-5" followed by "Zoom In" will get you to zoom factor 10. Specific zoom factors may also be accessed directly as Control keystrokes, e.g. Ctrl-5 will set zoom factor 5. Center centers the field. Toggle Zoom toggles between the current zoom/center values, and the unzoomed image.

Aspect recomputes the view so that the aspect ratio is 1.0. Aspect also integerizes the zoom factor (use the version in the View menu if you don't want integerization).

Fit Frame makes the display window the same size as the frame buffer. Note that autoscale has much the same effect, and allows you to resize the display window to any size you want, or view images to large to fit on the screen.

Enhancement Controls

At the top is a scrolled list of all the available colormaps. Click on the one you want to load it. You can add your own colormaps to this list.

The two sliders adjust the contrast (upper slider) and brightness (lower slider) of the display. The Invert button inverts the colormap (multiples the contrast by -1.0). Note that due to the use of the private colormap the sliders are a bit sluggish when dragged to window the display. If this is annoying, using MB3 in the display window is faster.

The Normalize button (on the bottom of the control panel) will normalize the enhancement, i.e. set the contrast and brightness to the default one-to-one values (1.0, 0.5). This is the preferred setting for many of the pseudocolor colortables and for private colormaps loaded from disk images.

Blink Controls

Blink frames is the list of frames to be blinked. When blink mode is in effect ximtool just cycles through these frames endlessly, pausing "blink rate" seconds between each frame. The same frame can be entered in the list more than once. To program an arbitrary list of blink frames, hit the Reset button and click on each blink frame button until it is set to the desired frame number.
The Blink Rate can be adjusted as slow or as fast as you want using the arrow buttons. If you set the blink rate small enough it will go to zero, enabling single step mode (see below).
The Register button registers all the blink frames with the current display frame. Frames not in the blink list are not affected.
The Match LUTs button sets the enhancement of all blink frames to the same values as the display frame. Frames not in the blink list are not affected.
The Blink button turns blink on and off. When the blink rate is set to zero the Blink button will single step through the blink frames, one frame per button press.

NOTE: you can blink no matter what ximtool options are in effect, but many of these will slow blink down. To get the fastest blink you may want to turn off the panner and coords box, and match the LUTs of all the blink frames. All the ximtool controls are fully active during blink mode, plus you can load frames etc.

Options:

Autoscale: If autoscale is enabled then at zoom=1, the frame buffer will be automatically scaled to fit within the display window. With autoscale disabled (the default), the image scale is more predictable, but the image may be clipped by the display window, or may not fill the display window.
Antialiasing: When dezooming an image, i.e., displaying a large image in a smaller display window, antialiasing causes all the data to be used to compute the displayed image. If antialiasing is disabled then image is subsampled to compute the displayed image. Antialiasing can prevent subsampling from omitting image features that don't fall in the sample grid, but it is significantly slower than dezooming via subsampling. The default is no antialising.
Tile Frames: The default display mode is to view one frame at a time. In tile frames mode, 2 or 4 frames may be viewed simultaneously in the display window. All the usual operations (zoom and pan, colortable enhancement, cursor readback, etc.) still work for each frame even when in tile frames mode.
Warnings: The warnings options toggles whether you see warning dialog boxes in situations like overwriting an existing file, clearing the frame buffer, etc.

Colormap Selection

By default XImtool will display images using either a grayscale colormap if loaded by a client, or a private colormap when loading an image from disk that contains a colormap. Each frame defines its own colormap so you can define different colormaps or enhancements for each frame, they will change automatically as you cycle through the frames.

Builtin Colormaps

Once loaded, the colormap may either be changed using the builtin colormap menu under the View menu button on the main window, or from the Enhancement box on the control panel. Ximtool has about a dozen colormap options builtin, other user-defined colormaps may optionally be loaded.

User-defined Colormaps

The cmap[12] and cmapDir[12] resources (or command line arguments are used to tell ximtool which specific colormaps to make available or where to look for colortables respectively. The colortables are loaded when ximtool starts up, or when it is reinitialized (e.g. by pressing the Initialize button in the control panel). Ximtool will ignore any files in the colormap directory which do not look like colortables. New colortables will also be added for each images loaded from disk.

The format of a user lookup table is very simple: each row defines one colortable entry, and consists of three columns defining the red, green, and blue values scaled to the range 0.0 (off) to 1.0 (full intensity).

        R G B
        R G B
        (etc.)

Blank lines and comment lines (# ...) are ignored.

Usually 256 rows are provided, but the number may actually be anything in the range 1 to 256. Ximtool will interpolate the table as necessary to compute the colortable values used in Ximtool. Ximtool uses at most 201 colors to render pixel data, so it is usually necessary to interpolate the table when it is loaded.

The name of the colortable as it will appear in the Ximtool control panel is the root name of the file, e.g., if the file is "rainbow.lut" the colortable name will be "rainbow". Lower case names are suggested to avoid name collisions with the builtin colortables. Private colormaps for disk images will be have the same name as the image loaded. If the same colortable file appears in multiple user colortable directories, the first one will be used.

The directory "luts" in the ximtool source directory contains a sample set of colortable files. This can be installed as /usr/local/lib/imtoolcmap when ximtool is installed.

Load Panel

The Load Panel allows you load images from disk directly to the frame buffer, this is analogous to loading an image on the command line except that browsing is possible. At present recognized formats include IRAF OIF format (i.e. .imh extension), simple FITS files, GIF, and Sun rasterfiles. The task will automatically sense the format of the image and load it appropriately. Images with private colormaps (such as GIF) will be loaded using the private colormap by default (meaning that changing the brightness/contrast enhancements will render a random-colored image). If the Grayscale button is enabled the image will be converted to grayscale and loaded with the standard grayscale colormap.

When loading new images the frame buffer configuration table (imtoolrc) will be searched for a frame buffer that is the same size or larger than the new image size, if no frame buffer can be found a custom buffer exactly the size of the image will be created. This means that the image may not fill the display window when loaded, or you may see a subsection of the image in the main display window. Setting the autoscale option will scale the entire image to fit the main display window.

Images with more colors than can be displayed will automatically be quantized to the number of available colors before display. Formats which allow more than 8-bit pixels will be sampled to determine an optimal range in the data to be used to compute the transformation to the number of display colors. This is the same transformation used by the IRAF DISPLAY task.

Directory browsing: The load panel contains a list of files in the current directory that may be selected for loading by selecting with left mouse button. If the file is a directory the contents of the new directory will be loaded, if it's a plain file an attempt will be made to load it as an image. Directories in the list are identified with a trailing '/' character, you will always see any directories available even if a filter is specified.
The Root button will reset the current directory to the system root directory. The Home button will reset the current directory to the user's login directory, the Up button moves up one directory level, and Rescan reloads the file list by rescanning the directory. The current working directory is given below the file selection window.
File Patterns: By default all files and directories will be listed. You may specify a filter to e.g. select only those files with a given extension like "*.fits" to list only files with a ".fits" extension. Directories will always be seen in the list and are identified with a trailing '/' character. Any valid unix pattern matching string will be recognized.
Direct File Load: If you know exactly which file you wish to load, you may enter its name in the Load File text box and either hit or the Load button to load it. An absolute or relative path name may be given, if a simple filename is specified it will be searched for in the current working directory.
Frame Selections: By default images will be loaded into frame number 1, you may select a different frame using the Frame menu button.

Save Panel

The Save Panel lets you save the current contents of the main display window to a disk file (including the Panner/Coords markers, any general graphics markers, or overlay graphics displayed by the client program). Presently, only the contents of the main display window may be saved, there is no facility for saving the undisplayed contents of the entire frame buffer other than to enable the autoscale feature. A limited number of formats are currently available, others will be added in future versions.

File Name: The File Name text box allows you to enter the file name of the saved file. A "%d" anywhere in the name will be replaced by a sequence number allowing multiple frames to be saved with unique names.
Format: The Format box allows you to choose the format of the image to be created. Not all formats are currently implemented.
Color: The Color box lets you choose the color type of the image to be created. The options will change depending on the format, e.g. FITS doesn't allow color so no color options will be allowed. Formats which allow 24-bit images will be written using the current colormap after converting to a 24-bit image, pseudocolor images will be written with the current colormap.

Print Panel

The Print Panel allows you dump the contents of the main display window as Enacpsulated Postscript to either a named printer device or to a disk file. The Print To selects the type of output, the Print Command box will adjust accordingly, either as a Unix printer command or as a file name. A "%d" anywhere in the name for disk output will be replaced by a sequence number allowing multiple frames to be saved with unique names. Selecting printers from the installed list will automatically change the command to be used to generate the output. This command does not necessarily need to be a printer command, the printer configuration file lets you define any command string to process the image.

Color Options

The Color box lets you choose the color type of the image to be created. PseudoColor or 24-bit postscript will be created using the current colormap.

Postscript Options

Orientation: Set the page orientation.
Paper Size: Select the paper size to be used.
Image Scale: Set the scale factor used to compute the final image size.

Processing Options

Auto Scale: The auto scale toggles whether or not the image is automatically scaled to fit the page. If not enabled, the image scale will be used to dtermine the output image size.
Auto Rotate: Auto rotate determines whether or not the image will be rotated to fit on the page. When set, an image larger than the current orientation will be rotated and possibly scaled to fit the page.
Max Aspect: Max Aspect takes images smaller than the page and automatically increases the scale so the image fills the page in the current orientation.
Annotate: The annotate option toggles whether or not the final file includes annotation such as the image title, a colorbar, and axis labels.

Printer selection

The printer selection list lets choose the printer to be used. The printer configuration file is /usr/local/lib/ximprint.cfg by default or may be reset using the printConfig resource. The format of the file is simply

	name < tab > command

The name value is what appears in the selection list and may be more than a single word, the command can be any command that accepts EPS input from a pipe, the two fields must be separated by a tab character. Normally the command will be a simple 'lpr -Pfoo' or some such, but can also include converters or previewers. At most 128 printer commands may be used.

Info Panel

The information panel is underused at present but is meant to provide basic information about the frame being displayed. It is updated to be current while changing enhancements, pan/zoom regions, or frame selection. In cases where the image title string is truncated in the main display window, the user can always pop up the info window to see the full title.

TclShell

The TclShell is mostly used as a development or debugging tool for the GUI. It allows the user to type commands directly to the TCL interpreter letting you send messages to the object manager or execute specific procedures in the TCL code that makes up the GUI. Most users will never need this, but for an example of what it does, bring it up and type a command such as

    send helpButton set background red

Cool, huh.

Acknowledgements

XImtool was developed by the IRAF Group at the National Optical Astronomy Observatories in Tucson, AZ.

This document was last updated 11/6/96.

Welcome to XImtool V1.1

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