
Warpimage(Operations)        Khoros         Warpimage(Operations)

     Tiepoint Operation

     There are two basic tiepoint operations - adding tiepoints
     and deleting tiepoints.  When the Tiepoint Operation toggle
     is set to "Add", mouse clicks in the source and target win-
     dows (or in the source zoom and target zoom windows) will
     add tiepoints at the location of the click;  when the
     Tiepoint Operation toggle is set to "Delete", mouse clicks
     in the source and target windows (or in the source zoom and
     target zoom windows) will delete tiepoints, provided that a
     tiepoint is located directly under the mouse at the time of
     the click.  The procedure used to add and delete tiepoints
     is determined by the Tiepoint Mode, described below.

     Tiepoint Mode

          Source And Destination

     When the Tiepoint Mode (controlled by the value of the [-
     tp_mode] flag at the start of execution) is set to Source
     And Destination, the procedure to add tiepoint pairs is as
     follows.  First, click the mouse at the desired location in
     either the source image or the source zoom window.  If the
     mouse is clicked in the source image, a red tiepoint will
     appear in the source image; if the region in which the new
     tiepoint is located is currently displayed in the source
     zoom window, a red tiepoint will also appear in the zoom
     window.  If the mouse is clicked in the source zoom window,
     it will always appear in both the source zoom window and the
     source image.  The tiepoint appears in red, indicating that
     you must now match it with a tiepoint in the target window.

     Now, click the mouse at the desired location in either the
     target image or the target zoom window.  If the mouse is
     clicked in the target image, a green tiepoint will appear in
     the target image; if the region in which the new tiepoint is
     located is currently displayed in the target zoom window, a
     green tiepoint will also appear in the zoom window.  If the
     mouse is clicked in the target zoom window, it will always
     appear in both the target zoom window and the target image.

     At the same time that the target tiepoint is created, its
     partner in the source image will change its color from red
     to green, indicating that a tiepoint pair has been esta-
     blished.  You may now repeat the process to create more
     tiepoint pairs.

          Source Only

     When the Tiepoint Mode is set to Source Only, tiepoints are
     only created on the source image;  in fact, there is no
     point in inputting a target image at all, as it will not be
     used. This option is useful when tiepoint information is
     already available for either the source or the target image,
     but the second tiepoint file needs to be created interac-
     tively.  The resulting tiepoint file can be used along with
     the original tiepoint file for warping the source image.
     vpolyco and vbilinco are two routines that will generate
     polynomial coefficients to map the source tiepoints onto the
     target tiepoints.  These coefficient files can then be used
     as the coefficients for vwarp to perform image warping.

     The procedure to add individual tiepoints is as follows.
     Click the mouse at the desired location in either the source
     image or the source zoom window.  If the mouse is clicked in
     the source image, a green tiepoint will appear in the source
     image; if the region in which the new tiepoint is located is
     currently displayed in the source zoom window, a green
     tiepoint will also appear in the zoom window.  If the mouse
     is clicked in the source zoom window, it will always appear
     in both the source zoom window and the source image. This
     process may be repeated as many times as necessary.

     Zoom Type & Zoom Factor

     There are two methods for zooming on the source and target
     images- Rubberband, and Point & Click.  Depending on what
     you are doing, one of the methods may be more appropriate
     than the other.

          Point & Click

     The Point & Click is the simpler, but less precise method of
     zooming. To change the location of the zoom area, click on
     the "Point & Click" action button, and follow that with a
     mouse click at the pixel in the image at which you want the
     center of the zoom area.  The contents of the zoom window
     will be immediately updated, so as to have the selected
     pixel of the image be at the center of the zoom window.
     Under "Zoom Factor", go to either the "Source" or "Destina-
     tion" selection, depending on whether you want to change the
     zoom factor of the source zoom window or the target zoom
     window.  Fill in the desired zoom factor, and hit <CR>. You
     will see the zoom window immediately update according to the
     new zoom factor.

          Rubberband

     The Rubberbanding method of zooming is a little more compli-
     cated, but more precise.  To use the Rubberbanding method,
     click on the action button labeled, "Rubberband".  Then, go
     to the image, and click the mouse on the desired location of
     the upper left hand corner of the zoom box to be created.
     Holding the mouse button down, move the mouse to the desired
     location of the lower right hand corner of the zoom box.
     The zoom box will be rubberbanded during this operation.
     When the desired area appears within the rubberbanded box,
     release the mouse button.  The zoom area will be set within
     the rubberbanded box. The zoom factor is computed according
     to the bounds of the rubberbanded box, and the contents of
     the zoom window are updated accordingly.  In addition, the
     contents of the zoom factor selection to the far right of
     the "Operations" pane will immediately be updated, informing
     you as to the exact zoom factor that was computed from the
     rubberbanding action.  Thus, when the Rubberbanding method
     of zooming is used, the "Zoom Factor" selection is an out-
     put, not an input.  The rubberbanded box will remain
     displayed in the image, to remind you of the exact location
     of the zoom area.

     Copyright 1992, University of New Mexico. All rights
     reserved.

Khoros                    Release: 1.0                          1

