Limelight finding number of targets

[erichuang]

How do you find the number of april tags detected by limelight?

[jdaming]

You must use the JSON output (LimelightHelpers is helpful) and look for the length of the fiducals array result.targets_Fiducials.length

Yes everyone wishes it was easier. I made an issue here.

[erichuang]

Thanks, I counted the number of occurrences of “pts” in the JSON dump since “pts” only occurs once per tag.

public int getNumTargets() {
    return countStringOccurrences(NetworkTableInstance.getDefault().getTable(m_name).getEntry("json").getString(""), "pts");
}

private int countStringOccurrences(String str, String substr) {
    int occurrences = 0;
    for (int i = 0; i < str.length()-substr.length()+1; i++) {
        if (str.substring(i, i+substr.length()).equals(substr)) {
            occurrences++;
        }
    }
    return occurrences;
}

[erichuang]

Now Limelight provides a number for the tag count, it is the 7th index of the botpose array Complete NetworkTables API | Limelight Documentation