Hoku is an image processing software

Hoku is used to process multispectral image data sets to recover writings that have been damaged or erased. It is a Java-base software package distributed free-of-charge, without warranty.

Dr. Keith T. Knox, creator of Hoku, independent imaging scientist and EMEL chief scientific advisor.
Hoku is a batch processing software package. Jobs are defined and parameters are set interactively with a graphical user interface, but jobs are run in batch mode until they conclude.

There are no interactive image processing methods available. You cannot touch-up or draw on an image with this software, but you can apply any of several image processing methods to enhance image details that otherwise are difficult to see.

Download Hoku

Hoku is available for a variety of platforms.

Latest Hoku version is:
v2.3, released on 29 November 2024.
New Features in version 2.3
Three new modules were added to the Cupboard, ImFill, Pause, and WriteStack.
ImFill replaces outlier values, within a window, with that window’s average value.
Pause is used in a flowchart to introduce a short delay. WriteStack will write out several images, one for each band of the input image.

One major change on Hoku for Macintosh computers, is that the new Mac version of Hoku will run on both a computer with an M-chip, or the older Intel chip. As a result, there is now only one version of Hoku for the Mac. There is also only one version for Windows. A Linux version is under development.

How To

To install the new Hoku application, you must have system administrator privileges on your computer. If you do not have such privileges, see if a system administrator will load the software for you. If neither is possible, then see the next section on how to install a version of Hoku without system administrator privileges.
 
Hoku applications are available for the macOS, Windows, and Linux. Download the Zip file containing the appropriate installation program from the following links. Double-click the downloaded Zip file to extract and decompress the installation folder.

Full instructions on how to install Hoku are contained in the “Instructions” file within each folder.
 
Installing Java on your computer is not needed for these applications.
They have the necessary Java runtime code embedded within them.

To run the InstallHoku.jar program, and to run Hoku itself, you will need to have Java software installed on your computer. See the Installing Java section below on where to find and install Java.

Next, download  ->  InstallHoku.jar
 
The best way to run InstallHoku.jar is to bring up a terminal window. In Windows, that is a command prompt. In macOS, that is Terminal.app that you find in / Applications. In Linux, that a Terminal window. Now, change to the directory where you put InstallHoku.jar when you downloaded it. That might be the Desktop or it might be Downloads.

For the Desktop, that command would be:
 
             cd Desktop
 
Given that you have already installed Java, you can run InstallHoku.jar with the command:
 
             java -jar InstallHoku.jar
 
This installation program will determine which type of computer you are using, either Windows, macOS, or Linux, and install the appropriate routines.  Follow the instructions in the program.   You may delete InstallHoku.jar when it finishes.
 
InstallHoku.jar will install a folder, named HokuUtilities, in your home directory. Do not delete that folder or modify anything within it. The install program will put an icon shortcut on your computer Desktop which can be used to start Hoku.

To upgrade Hoku from the 2.0 version, on Windows, you will need to first uninstall Hoku. Download the appropriate zip file for your computer platform and double-click on the installer.  Your existing data, on your Hoku Shelf and Hoku Desktop will not be changed.  All of your existing data will be available to you in the new version of Hoku.

Previous versions of Hoku ran on Java version 8 (1.8).  This latest version of Hoku requires at least Java version 17. We recommend that you download Java 21 from:  
 
      https://www.oracle.com/java/technologies/downloads/.

Select the “JDK 21” tab, then either the “Mac”, “Windows”, or “Linux” tab.  This upgrade beyond Java 1.8 was necessary, because Java version 8 does not have a version that runs native code on the new Apple M1/2/3 hardware chips.

Version 21 is a long-term, stable version that has a native code for the Apple M1/2/3 chips. On Windows, just download the Windows version of Java 21, and for Linux on a computer with Intel processors, download the Linux_x64 version.  For Linux on a Mac with Apple silicon (M-chips), download Linux_arm64. For the Mac, determine if you have the M1/2/3 chips from your computer, then download either the “ARM64” version of the code, or the “x64” version of the code if you have an Intel Mac.

Coming soon…

Learn Hoku

A series of videos can help you familiarize with Hoku

License

Copyright (C) 2021-2025  Keith T. Knox
 
 This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; version 2 of the License.
 
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
 
You can read the GNU General Public License in LICENSE.txt. You may also obtain a copy of the license by writing to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 
Keith Knox

29 November 2024