lifview: Light Field Viewer

The lifview program will allow you to interactively view light fields. This page describes how to download and configure the viewer to load light fields directly from your web browser. After you have downloaded and configured the viewer, click here to see some sample light fields from the Stanford Light Fields Archive.

The lifview program is available for the following platforms:

SGI

This version of lifview will run on SGI's running Irix 5.0 or higher.
To download lifview, hold down the shift key and click on the link below:

Download lifview.gz v.1.0 (SGI)
Change the permissions of the program to make it executable ( chmod +x lifview ) and make sure its directory is in your path.

All of our sample light fields are gzipped to save space (and transfer time). If you use Netscape as your web browser, you can configure it to automatically decompress a light field and launch the lifview program when you click on one of our links. To do this:

Add the following line to your .mailcap file, so that your browser will automatically run lifview when you click on light field files:
```
application/x-lif; lifview %s
```
If your browser does not automatically decompress gzipped files, add the following line to your mime.types file:
```
enc=x-gzip           exts=gz            icon=internal-gopher-unknown
```
To find out where your mime.types file is located, look at the Options -> General Preferences -> Helpers menu.
Exit and restart your web browser, so that it will re-read your .mailcap and mime.types files.

If you cannot configure your browser to decompress gzipped files, the current version of the viewer will accept gzipped files and perform the decompression for you. You must have the "gzip" program in your directory path for this to work.

At this point, it should run the lifview program whenever you click on a light field. See the Running lifview section below for a brief primer on how to control the viewer.

PC

This version of lifview will run on PCs running Windows 95 or NT.
To download lifview, hold down the shift key and click on the link below:

Download lifview.exe v1.0 (PC)

All of our sample light fields are gzipped to save space (and transfer time).

If you use Netscape as your web browser, you can configure it to automatically launch the lifview program when you click on one of our links by making changes to the Options -> General Preferences -> Helpers menu.

All of our sample light fields are gzipped to save space (and transfer time). If you have WinZip (a popular shareware program), it can decompress .gz files. Otherwise, you can download gzip-1_2.exe , a self-extracting PC version of the free gzip program. After you download it, click on its icon to make it decompress itself.

We have not found a way to configure the PC version of Netscape to automatically decompress a file before launching an application (if you know how, tell us!). Instead, you can decompress the file by either:

dragging the file's icon onto WinZip, which will decompress the file and create a new file, or
bringing up an MSDOS prompt and typing gzip -d -N < filename > , which will also create a new file.

Alternatively, the current version of the viewer will accept gzipped files and perform the decompression for you. You must have "gzip.exe" in your directory path for this to work.

Once you have the icon for the uncompressed file, drag it onto the lifview program icon. This should launch the viewer. It may take a few seconds for the window to appear, especially for large files.

Running lifview

Run lifview without any arguments to print out its command-line options:


Usage: lifview [-v] [-size <x> <y>] [-zoom <z>] [-lerp <mode>] 
               [-refine <mode>] <lightfield>

     -v              Verbose on

     -size <x> <y>   Size (in pixels) of display window

     -zoom <z>       Zoom factor for display window
                     (The actual window size will be x*z, y*z)

     -lerp uvst      Start with full uvst interpolation filter
     -lerp uv        Start with only uv interpolation (default)
     -lerp st        Start with only st interpolation
     -lerp none      Start with point sampling

     -refine all     Auto-refine image when viewer isn't moving
                     (this refines both uvst and zoom)
     -refine uvst    Auto-refine uvst interpolation only
     -refine zoom    Auto-refine pixel zoom only
     -refine off     Never auto-refine image

     <lightfield>    This can be the name of either a .lif
                     file or a .lid file.  If it is a .lid
                     file, it will tell lifview where to
                     find the raw .rgb images.

Navigation

Use the mouse to move around inside the viewer. The controls are the same as SGI's Inventor toolkit:

Drag the left mouse button to rotate the object around its center.
Hold down the shift key and drag the left mouse button sideways to rotate the object horizontally around its center. (The shift key disables vertical rotation.)
Drag the middle mouse button (right mouse button on the PC) to translate the object sideways.
Hold down the shift key and drag the middle mouse button (right mouse button on the PC) to pan the view around the viewer's location.
Drag both buttons up and down to zoom in and out.
The spacebar brings you back to the starting position. (This is useful if you get lost in space.)
The key exits.

You can also control several drawing paramaters with a pop-up menu. To get this menu, hold down the right mouse button (on an SGI), or go to the pull-down menu (PC).

Distribution notice

Except for commercial resale, lease, license or other commercial transactions, permission is hereby given to use, copy, and/or modify this software, provided that the above copyright notice and this permission notice appear in all copies of this software. No part of this software or any derivatives thereof may be used in the production of computer models for resale or for use in a commercial product.

This software is provided "as is" and without warranty of any kind, express, implied or otherwise, including without limitation, any warranty of merchantability or fitness for a particular purpose.

If you have any questions, problems, concerns, or suggestions about the lightpack software, send mail to:

lightpack@graphics.stanford.edu

back to the LightPack home page.

webmaster@graphics.stanford.edu