jMISB

About

jMISB is an open source Java library implementing various MISB standards. It leverages the excellent work by bytedeco on bringing video support to Java. Stay tuned here for updates, and please join us on gitter if you need help or would like to participate!

Why jMISB?

The Motion Imagery Standards Board, or MISB's mission is to develop and maintain standards for interoperability between motion imagery systems in use within the Department of Defense (DoD) and Intelligence Community (IC).

The goal of the jMISB project is to provide an open implementation of these standards and allow government and industry to leverage them more easily and effectively. The jMISB project is not affiliated with, nor endorsed by MISB in any way.

Scope

The MISB has been quite prolific in creation of new standards since its inception in 2000. As of April 2021, over four dozen standards are listed on its web site. While the scope of the jMISB project is to support as many of these standards as possible, the initial focus will be on those in most widespread use.

The table below lists the status of currently-supported standards:

jMISB aims to be cross-platform to run on any modern operating system. However, since efficient video coding tends to leverage natively-compiled binaries, currently platform support is limited to Linux, Windows, and MacOS. Android is next on our roadmap (see #253).

Including in Your Project

If you are using a dependency management tool such as Maven with access to the Central Repository, you can configure it to use jMISB as a dependency. For Maven, add the following to your pom.xml:

    <dependency>
        <groupId>org.jmisb</groupId>
        <artifactId>jmisb-api</artifactId>
        <version>1.12.0</version>
    </dependency>

For Gradle, include the following:

dependencies {
    implementation 'org.jmisb:jmisb-api:1.12.0'
}

API Usage

A primary objective of jMISB is to provide an easy-to-use API allowing non-domain experts to create applications leveraging MISB standards.

The primary API for reading/writing video and metadata is in the org.jmisb.api package. See the javadocs for an extensive API reference.

Below is a simple example of reading a network stream containing video and (optionally) metadata.

        try (IVideoStreamInput stream = new VideoStreamInput())
        {
            stream.open("udp://127.0.0.1:35800");
            stream.addFrameListener(new ExampleProcessor());
            stream.addMetadataListener(new ExampleProcessor());
            while (stream.isOpen()) {
                Thread.sleep(1000);
            }
        }
        catch (IOException e) {
            System.out.println("Could not open the stream");
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

The ExampleProcessor class simply needs to implement the IVideoListener and IMetadataListener interfaces to receive video and metadata asynchronously as the data arrives.

class ExampleProcessor implements IVideoListener, IMetadataListener
{
    @Override
    public void onVideoReceived(VideoFrame frame)
    {
        BufferedImage image = frame.getImage();
        System.out.println("Center pixel RGB: " +
            image.getRGB(image.getWidth()/2, image.getHeight()/2));
    }

    @Override
    public void onMetadataReceived(MetadataFrame frame)
    {
        IMisbMessage metadata = frame.getMisbMessage();
        if (metadata instanceof UasDatalinkMessage)
        {
            UasDatalinkMessage msg = (UasDatalinkMessage)metadata;
            System.out.println("Sensor position: " +
                msg.getField(UasDatalinkTag.SensorLatitude).getDisplayableValue() +
                ", " +
                msg.getField(UasDatalinkTag.SensorLongitude).getDisplayableValue());
        }
        else if (metadata instanceof SecurityMetadataMessage)
        {
            // ...
        }
    }
}

The result of msg.getField(UasDatalinkTag.SensorLatitude) will be an instance of the SensorLatitude class (implementing IUasDatalinkValue).

For more complete examples of usage, see the examples directory, as well as viewer, a Java Swing-based tool for displaying video and metadata.

Elevation

While not a core focus, jMISB provides some elevation / terrain related support. This includes:

• EGM 96 conversion of altitude between ellipsoid (aka HAE) and geoidal (aka MSL).

Building

To build the library from the command line, simply run the Maven command:

mvn install

This will compile the source code, run unit tests, and install the JARs to your local Maven repository.

To get started, you may want to run jmisb-viewer and experiment with some test data. This is a sample application intended mainly to aid in development. To run it from the command line, issue:

cd viewer
mvn exec:exec

Versioning

jMISB adheres to semantic versioning to communicate to client developers about the scope of changes in any new release. Version numbers are formatted as major.minor.patch, where:

1. The major number is incremented to indicate incompatible API changes.
2. The minor number is incremented to indicate new functionality has been added, but in a backward-compatible manner.
3. The patch number is incremented to indicate a backwards-compatible bug fix.

In other words, users of the library should feel comfortable updating to use a new version unless the major number has changed. In general, users should keep up to date with the latest patch release for a given major.minor release branch.

Use of -SNAPSHOT within the version number indicates that the version is for internal development only, i.e., the artifact is not to be used in a production environment.