# The PanoramIX Authoring Tool

## Version 0.1.4.92, February 26, 1998

## 4. The Edit Menu

The Edit Menu supports the following functions:

1. Undo and Redo Operations
2. Copy and Paste Operations
3. Partial Panoramas
4. Variable Resolution
5. Hot Spots
6. Depth Maps
7. Edit Flat Side Images
8. Edit Panoramic Images
9. Edit Top Images and Bottom Images
10. Edit Sprites

### 4.1 Undo and Redo Operations

The Undo function cancels the most recent previous panorama editing operation. This can be repeated for up to 25 previous operations. The Redo function restores the editing operation cancelled by the most recent Undo.

The list of previous editing operations is cleared when any image is imported or a panorama is loaded. The Load Edit List operations in the File menu can be used to return to a previous editing state after any number of operations, or after exiting and reloading the PanoramIX Authoring Tool.

Back to the Edit Menu.

Back to the PanoramIX Authoring Tool.

### 4.2 Copy and Paste Operations

The Copy and Paste operations in the Edit menu are modally dependent on the stste of the EditImage window. If the EditImage window is open, then the Edit menu will have an entry identified as Copy Edit Image. Selecting the Copy Edit Image entry causes the currently selected image shown in the Edit Image window to be copied into the Windows clipboard. The complete unmodified image is copied to the clipboard. Any clipping lines shown in the Edit Image window are not drawn on this copy, and the cropping boundaries are ignored.

If the EditImage window is not open, then the Edit menu will have an entry identified as Copy Panorama. Selecting the Copy Panorama entry causes the current panoramic background image to be copied into the Windows clipboard. The complete cylindrical panorama is copied to the clipboard.

After an image has been copied to the clipboard, it can be pasted into any Windows or MacOS image processing application. After pasting this image into an image processing application, the image may be modified using any facilities provided by the chosen image processing application. After the image has been modified in this way, the complete modified image or any rectangular portion of the modified image may be copied back to the clipboard.

After an image has been copied into the clipboard, the contents of the clipboard can be pasted into the current Edit Image. The pasted image is initially positioned in the upper left corner of the EditImage window, and the cursor changes to a hand indicating the the operation is in "paste mode" and the position of the pasted image may be shifted horizontally and vertically until it is located in a suitable position.

When the pasted image has been shifted into the desired located, it can be dropped into this location by clicking the left mouse button anywhere outside the pasted region, or by clicking the right mouse button anywhere in the Edit Image window or in the main window.

Back to the Edit Menu.

Back to the PanoramIX Authoring Tool.

### 4.3 Maximum Azimuth for Partial Panoramas

The azimuth angle specifies the location of a single column of pixels with respect to a vertical axis in the center of a cylinder. A complete panorama covers all azimuth angles from 0 to 360 degrees. A partial panorama is defined by a range of azimuth angles covering less than 360 degrees. A partial panorama may be needed for situations in which the data for certain ranges of azimuth angles is not available.

By default, every panorama is initially assumed to be complete (360 degrees). In the case of a partial panorama, one must tell the panorama editor the value of the maximum azimuth angle appropriate to the available data. This value may be specified through the maximum_angle parameter in a Raw Image Control File. In addition, this angle may be specified by selecting the Maximum Azimuth entry in the Edit menu.

Selecting the Maximum Azimuth entry in the Edit menu opens the Maximum Azimuth dialog. This is a very simple dialog which allows one to specify the maximum azimuth angle in degrees. After entering a new maximum azimuth value, one may choose one of three buttons: OK, Apply, and Close. The OK button updates the current panorama based on the specified angle and closes the dialog. The Apply button applies the specified angle to the panorama so the effect of this change may be seen in the main window, but the dialog is not closed. This allows further changes to be tried before closing the Maximum Azimuth dialog. The Close button closes the dialog without saving the specified angle. In this case, the maximum azimuth reverts to either the original value or the value specified for the previous use of the Apply button.

Back to the Edit Menu.

Back to the PanoramIX Authoring Tool.

### 4.4 Panorama Resolution

The principal function of the panorama editor is to assemble a set of side images into a single seamless panoramic image. This panoramic image has horizontal and vertical dimensions determined by the dimensions of the side images. These dimensions are based on the objective of determining the smallest possible image that does not lose data. This ensures that every pixel in the input images corresponds to at least one pixel in the resulting panorama. Although this objective may be satisfactory for most situations, there can be conditions in which a user may want to force the panorama to have larger or smaller dimensions. For example, a user may be willing to lose some data in order to minimize the size of the panoramic image, or a user may want to force the panorama editor to oversample the panoramic image, then use a more sophisticated filtering algorithm to reduce the size of the panoramic image while avoiding aliasing artifacts resulting from the simple point-sampling methods employed by the panorama editor.

The default dimensions of the panoramic image may be overridden by selecting the Resolution entry in the Edit menu. This opens the Resolution dialog. The resolution dialog is a very simple dialog with only a single numerical parameter. This value is a numerical factor expressed as a percentage value. This factor is applied to both the horizontal and vertical dimension of the panoramic image. For example, an entry of 150% will cause the horizontal and vertical dimensions of the panoramic image to be set at values 1.5 times as large as the values that would be chosen otherwise, leading to 2.25 times as many pixels.

The value specified on the Resolution dialog does not take effect until the OK button or the Apply button is selected. The OK button closes the Resolution dialog after updating the panorama. The Apply button updates the panorama, but leaves the Resolution dialog open so further changes may be tested. The Close button closes the Resolution dialog without updating the panorama. This cancels any changes made to the Resolution factor since most recent use of the Apply button.

Back to the Edit Menu.

Back to the PanoramIX Authoring Tool.

### 4.6 Depth Maps

This function has not yet been implemented. Stay tuned.

A depth map is an array of data values indicating the distance from the center point of the panorama to the object responsible for color of each pixel in the color image. The values stored in this array actually specify 1/Z, where "Z" is the distance from the axis of the cylinder to the object seen at each pixel. Consequently, a value of zero in a depth map indicates an infinite distance from the axis of the corresponding pixel. A value of 255 represents the closest possible distance of a pixel from the center of the panorama.

This dialog has two buttons labelled "Copy Depth Map" and "Paste Depth Map". When the "Copy Depth Map" button is selected, the depth map for the current Edit Image is copied to the clipboard. If no depth map has been loaded, imported, or defined, an depth map of all zeroes will be generated for all images. The depth values will be placed in the red channel of the copied image. The green and blue channels will contain a "ghost" of the original color image. This ghost image is used only for reference, to assist in synchronizing depth values with objects in the scene.

After a depth map has been copied to the clipboard, it may be pasted into any image processing application, such as Adobe Photoshop. The chosen image processing application can then be used to paint in depth values using shades of red or shades of gray. Dark values will indicate distant elements of a scene, and bright values will indicate nearby elements of a scene.

After painting in suitable depth values, the resulting image can be copied back to the clipboard from the image process application. The "Paste Depth Map" button may then be selected to copy the depth map from the clipboard to the currently selected Edit Image.

After establishing a depth map for the panoramic background, animated sprites will be visible where the depth value associated with the sprite is greater then the value found in the depth map, and portions of a sprite having depth values less than the corresponding values in the depth map will be hidden.

Back to the Edit Menu.

Back to the PanoramIX Authoring Tool.

Last modified February 27, 1998.
wluken@watson.ibm.com