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​
getTV

Returns whether the camera currently sees a valid target. 
boolean hasTarget = LimelightHelpers.getTV("limelight");
​
limelightName
string
required
Name of the Limelight NetworkTables table. Pass an empty string "" to use the default "limelight" table.
​
returns
boolean
true if a valid target is present, false otherwise.

​
getTX

Returns the horizontal offset from the configured crosshair to the primary target, in degrees. 
double tx = LimelightHelpers.getTX("limelight");
​
limelightName
string
required
Name of the Limelight NetworkTables table.
​
returns
double
Horizontal offset angle in degrees. Negative values are to the left of the crosshair.

​
getTY

Returns the vertical offset from the configured crosshair to the primary target, in degrees. 
double ty = LimelightHelpers.getTY("limelight");
​
limelightName
string
required
Name of the Limelight NetworkTables table.
​
returns
double
Vertical offset angle in degrees. Negative values are below the crosshair.

​
getTXNC

Returns the horizontal offset from the principal pixel to the primary target, in degrees. This is the most accurate 2D angular metric when using a calibrated camera and you do not need adjustable crosshair functionality. 
double txnc = LimelightHelpers.getTXNC("limelight");
​
limelightName
string
required
Name of the Limelight NetworkTables table.
​
returns
double
Horizontal offset in degrees from the principal pixel, with no crosshair adjustment applied.

​
getTYNC

Returns the vertical offset from the principal pixel to the primary target, in degrees. Prefer this over getTY for calibrated cameras that do not require a moveable crosshair. 
double tync = LimelightHelpers.getTYNC("limelight");
​
limelightName
string
required
Name of the Limelight NetworkTables table.
​
returns
double
Vertical offset in degrees from the principal pixel, with no crosshair adjustment applied.

​
getTA

Returns the target area as a percentage of the full image (0–100). 
double area = LimelightHelpers.getTA("limelight");
​
limelightName
string
required
Name of the Limelight NetworkTables table.
​
returns
double
Target area as a percentage of the image, from 0 (no target) to 100 (full frame).

​
getT2DArray

Returns an array of 17 targeting metrics in a single NetworkTables read. 
double[] t2d = LimelightHelpers.getT2DArray("limelight");
// t2d[0]  = targetValid
// t2d[1]  = targetCount
// t2d[2]  = targetLatency
// t2d[3]  = captureLatency
// t2d[4]  = tx
// t2d[5]  = ty
// t2d[6]  = txnc
// t2d[7]  = tync
// t2d[8]  = ta
// t2d[9]  = tid
// t2d[10] = targetClassIndexDetector
// t2d[11] = targetClassIndexClassifier
// t2d[12] = targetLongSidePixels
// t2d[13] = targetShortSidePixels
// t2d[14] = targetHorizontalExtentPixels
// t2d[15] = targetVerticalExtentPixels
// t2d[16] = targetSkewDegrees
​
limelightName
string
required
Name of the Limelight NetworkTables table.
​
returns
double[]
A 17-element array: [targetValid, targetCount, targetLatency, captureLatency, tx, ty, txnc, tync, ta, tid, targetClassIndexDetector, targetClassIndexClassifier, targetLongSidePixels, targetShortSidePixels, targetHorizontalExtentPixels, targetVerticalExtentPixels, targetSkewDegrees].

​
getTargetCount

Returns the number of targets currently detected. Reads index 1 of the T2D array. 
int count = LimelightHelpers.getTargetCount("limelight");
​
limelightName
string
required
Name of the Limelight NetworkTables table.
​
returns
int
Number of detected targets. Returns 0 if the T2D array is not the expected length.

​
getClassifierClass

Returns the class name string from the currently running neural classifier pipeline. 
String className = LimelightHelpers.getClassifierClass("limelight");
​
limelightName
string
required
Name of the Limelight NetworkTables table.
​
returns
string
The class name of the current classifier result (e.g. "cube", "cone").

​
getClassifierClassIndex

Returns the numeric class index from the currently running neural classifier pipeline. Reads index 11 of the T2D array. 
int classIdx = LimelightHelpers.getClassifierClassIndex("limelight");
​
limelightName
string
required
Name of the Limelight NetworkTables table.
​
returns
int
Class index from the classifier pipeline. Returns 0 if the T2D array is not the expected length.

​
getDetectorClass

Returns the class name string of the primary result from the currently running neural detector pipeline. 
String detectedClass = LimelightHelpers.getDetectorClass("limelight");
​
limelightName
string
required
Name of the Limelight NetworkTables table.
​
returns
string
The class name of the primary detector result.

​
getDetectorClassIndex

Returns the numeric class index of the primary result from the currently running neural detector pipeline. Reads index 10 of the T2D array. 
int detectorIdx = LimelightHelpers.getDetectorClassIndex("limelight");
​
limelightName
string
required
Name of the Limelight NetworkTables table.
​
returns
int
Class index from the detector pipeline. Returns 0 if the T2D array is not the expected length.

​
getLatency_Pipeline

Returns the pipeline processing latency contribution in milliseconds. 
double pipelineLatencyMs = LimelightHelpers.getLatency_Pipeline("limelight");
​
limelightName
string
required
Name of the Limelight NetworkTables table.
​
returns
double
Pipeline processing latency in milliseconds.

​
getLatency_Capture

Returns the image capture latency in milliseconds. 
double captureLatencyMs = LimelightHelpers.getLatency_Capture("limelight");
​
limelightName
string
required
Name of the Limelight NetworkTables table.
​
returns
double
Capture latency in milliseconds.

​
getCurrentPipelineIndex

Returns the index of the currently active pipeline (0–9). 
double pipelineIndex = LimelightHelpers.getCurrentPipelineIndex("limelight");
​
limelightName
string
required
Name of the Limelight NetworkTables table.
​
returns
double
Active pipeline index, between 0 and 9 inclusive.

​
getCurrentPipelineType

Returns a string describing the active pipeline type. 
String pipelineType = LimelightHelpers.getCurrentPipelineType("limelight");
// e.g. "retro", "apriltag", "neuraldetector", "neuralclassifier"
​
limelightName
string
required
Name of the Limelight NetworkTables table.
​
returns
string
Pipeline type identifier string (e.g. "retro", "apriltag").

​
getJSONDump

Returns the full JSON results string published by the Limelight each frame. 
String json = LimelightHelpers.getJSONDump("limelight");
​
limelightName
string
required
Name of the Limelight NetworkTables table.
​
returns
string
Raw JSON string containing all current pipeline results.

​
getLatestResults

Parses the JSON results dump and returns a LimelightResults object. Includes parse timing if profileJSON is enabled. 
LimelightHelpers.LimelightResults results = LimelightHelpers.getLatestResults("limelight");

if (results.error == null) {
    double tx = results.tx;
    LimelightHelpers.LimelightTarget_Fiducial[] tags = results.targets_Fiducials;
}
JSON parsing adds latency. Prefer direct NT getters (getTV, getTX, etc.) or getT2DArray for time-critical loops.
​
limelightName
string
required
Name of the Limelight NetworkTables table.
​
returns
LimelightResults
Parsed results object. Check results.error for a non-null value before using results.

​
getFiducialID

Returns the ID of the primary tracked fiducial/AprilTag. 
double tagId = LimelightHelpers.getFiducialID("limelight");
​
limelightName
string
required
Name of the Limelight NetworkTables table.
​
returns
double
Fiducial ID of the primary tracked AprilTag, or 0 if none.

​
getNeuralClassID

Returns the neural classifier class ID string for the primary result. 
String classId = LimelightHelpers.getNeuralClassID("limelight");
​
limelightName
string
required
Name of the Limelight NetworkTables table.
​
returns
string
Neural classifier class ID string.

​
getHeartbeat

Returns a counter that increments once per frame. Use this to verify the camera is connected and actively publishing. 
double hb = LimelightHelpers.getHeartbeat("limelight");
​
limelightName
string
required
Name of the Limelight NetworkTables table.
​
returns
double
Heartbeat counter. Rolls over at some large value. If it stops changing, the camera may be disconnected.

​
getTargetColor

Returns the average color observed under the crosshair region as a BGR array. 
double[] color = LimelightHelpers.getTargetColor("limelight");
double blue  = color[0];
double green = color[1];
double red   = color[2];
​
limelightName
string
required
Name of the Limelight NetworkTables table.
​
returns
double[]
Three-element array in BGR order: [Blue, Green, Red].

​
getRawBarcodeData

Returns decoded data strings from all barcodes detected in the current frame. 
String[] barcodes = LimelightHelpers.getRawBarcodeData("limelight");
for (String data : barcodes) {
    System.out.println("Decoded: " + data);
}
​
limelightName
string
required
Name of the Limelight NetworkTables table.
​
returns
string[]
Array of decoded barcode content strings. Empty array if no barcodes are detected.

​
getCornerCoordinates

Returns the corner coordinates of the primary detected target as a flat array of alternating x/y values. Requires Send Contours to be enabled in the Limelight Output tab. 
double[] corners = LimelightHelpers.getCornerCoordinates("limelight");
// corners = [x0, y0, x1, y1, x2, y2, x3, y3, ...]
​
limelightName
string
required
Name of the Limelight NetworkTables table.
​
returns
double[]
Flat array of corner coordinates in [x0, y0, x1, y1, ...] order. Empty if no target or Send Contours is disabled.

​
getRawFiducials

Returns low-latency raw AprilTag detection results directly from NetworkTables, bypassing JSON parsing. 
LimelightHelpers.RawFiducial[] fiducials = LimelightHelpers.getRawFiducials("limelight");
for (LimelightHelpers.RawFiducial f : fiducials) {
    System.out.println("Tag ID: " + f.id + ", dist: " + f.distToCamera);
}
​
limelightName
string
required
Name of the Limelight NetworkTables table.
​
returns
RawFiducial[]
Array of RawFiducial objects. Each contains: id, txnc, tync, ta, distToCamera, distToRobot, ambiguity. Returns an empty array if data is malformed.

​
getRawDetections

Returns low-latency raw neural detector results directly from NetworkTables, bypassing JSON parsing. 
LimelightHelpers.RawDetection[] detections = LimelightHelpers.getRawDetections("limelight");
for (LimelightHelpers.RawDetection d : detections) {
    System.out.println("Class: " + d.classId + ", txnc: " + d.txnc);
}
​
limelightName
string
required
Name of the Limelight NetworkTables table.
​
returns
RawDetection[]
Array of RawDetection objects. Each contains: classId, txnc, tync, ta, and four corner points (corner0_X/Y through corner3_X/Y). Returns an empty array if data is malformed.

​
getRawTargets

Returns low-latency raw target contour results directly from NetworkTables. Returns ungrouped contours in normalized screen space (−1 to 1). 
LimelightHelpers.RawTarget[] targets = LimelightHelpers.getRawTargets("limelight");
for (LimelightHelpers.RawTarget t : targets) {
    System.out.println("txnc: " + t.txnc + ", tync: " + t.tync);
}
​
limelightName
string
required
Name of the Limelight NetworkTables table.
​
returns
RawTarget[]
Array of RawTarget objects (up to 3). Each contains: txnc, tync, ta. Returns an empty array if data is malformed.

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