diff --git a/c/detectNet.cpp b/c/detectNet.cpp
index b113a5982..41e36ed21 100644
--- a/c/detectNet.cpp
+++ b/c/detectNet.cpp
@@ -660,7 +660,7 @@ int detectNet::postProcessSSD_UFF( Detection* detections, uint32_t width, uint32
 		if( object_data[2] < mConfidenceThreshold )
 			continue;
 
-		detections[numDetections].Instance   = -1; //numDetections; //(uint32_t)object_data[0];
+		detections[numDetections].TrackID   = -1; //numDetections; //(uint32_t)object_data[0];
 		detections[numDetections].ClassID    = (uint32_t)object_data[1];
 		detections[numDetections].Confidence = object_data[2];
 		detections[numDetections].Left       = object_data[3] * width;
@@ -722,7 +722,7 @@ int detectNet::postProcessSSD_ONNX( Detection* detections, uint32_t width, uint3
 		// populate a new detection entry
 		const float* coord = bbox + n * numCoord;
 
-		detections[numDetections].Instance   = -1; //numDetections;
+		detections[numDetections].TrackID   = -1; //numDetections;
 		detections[numDetections].ClassID    = maxClass;
 		detections[numDetections].Confidence = maxScore;
 		detections[numDetections].Left       = coord[0] * width;
@@ -802,7 +802,7 @@ int detectNet::postProcessDetectNet( Detection* detections, uint32_t width, uint
 				// create new entry if the detection wasn't merged with another detection
 				if( !detectionMerged )
 				{
-					detections[numDetections].Instance   = -1; //numDetections;
+					detections[numDetections].TrackID   = -1; //numDetections;
 					detections[numDetections].ClassID    = z;
 					detections[numDetections].Confidence = coverage;
 				
@@ -872,7 +872,7 @@ int detectNet::postProcessDetectNet_v2( Detection* detections, uint32_t width, u
 				LogDebug(LOG_TRT "rect x=%u y=%u  conf=%f  (%f, %f)  (%f, %f) \n", x, y, confidence, x1, y1, x2, y2);
 			#endif
 				
-				detections[numDetections].Instance   = -1; //numDetections;
+				detections[numDetections].TrackID   = -1; //numDetections;
 				detections[numDetections].ClassID    = c;
 				detections[numDetections].Confidence = confidence;
 				detections[numDetections].Left       = x1;
@@ -902,24 +902,30 @@ int detectNet::clusterDetections( Detection* detections, int n )
 		{
 			// if the intersecting detections have different classes, pick the one with highest confidence
 			// otherwise if they have the same object class, expand the detection bounding box
+		#ifdef CLUSTER_INTERCLASS
 			if( detections[n].ClassID != detections[m].ClassID )
 			{
 				if( detections[n].Confidence > detections[m].Confidence )
 				{
 					detections[m] = detections[n];
 
-					detections[m].Instance = -1; //m;
+					detections[m].TrackID = -1; //m;
 					detections[m].ClassID = detections[n].ClassID;
-					detections[m].Confidence = detections[n].Confidence;					
+					detections[m].Confidence = detections[n].Confidence;	
 				}
+				
+				return 0; // merged detection
 			}
 			else
+		#else
+			if( detections[n].ClassID == detections[m].ClassID )
+		#endif
 			{
 				detections[m].Expand(detections[n]);
 				detections[m].Confidence = fmaxf(detections[n].Confidence, detections[m].Confidence);
-			}
 
-			return 0; // merged detection
+				return 0; // merged detection
+			}
 		}
 	}
 
@@ -949,7 +955,7 @@ void detectNet::sortDetections( Detection* detections, int numDetections )
 
 	// renumber the instance ID's
 	//for( int i=0; i < numDetections; i++ )
-	//	detections[i].Instance = i;	
+	//	detections[i].TrackID = i;	
 }
 
 
@@ -1008,7 +1014,7 @@ bool detectNet::Overlay( void* input, void* output, uint32_t width, uint32_t hei
 	}
 			
 	// class label overlay
-	if( (flags & OVERLAY_LABEL) || (flags & OVERLAY_CONFIDENCE) )
+	if( (flags & OVERLAY_LABEL) || (flags & OVERLAY_CONFIDENCE) || (flags & OVERLAY_TRACKING) )
 	{
 		static cudaFont* font = NULL;
 
@@ -1025,38 +1031,42 @@ bool detectNet::Overlay( void* input, void* output, uint32_t width, uint32_t hei
 		}
 
 		// draw each object's description
-		std::vector< std::pair< std::string, int2 > > labels;
-
+	#ifdef BATCH_TEXT
+		std::vector<std::pair<std::string, int2>> labels;
+	#endif 
 		for( uint32_t n=0; n < numDetections; n++ )
 		{
 			const char* className  = GetClassDesc(detections[n].ClassID);
 			const float confidence = detections[n].Confidence * 100.0f;
 			const int2  position   = make_int2(detections[n].Left+5, detections[n].Top+3);
 			
+			char buffer[256];
+			char* str = buffer;
+			
+			if( flags & OVERLAY_LABEL )
+				str += sprintf(str, "%s ", className);
+			
+			if( flags & OVERLAY_TRACKING && detections[n].TrackID >= 0 )
+				str += sprintf(str, "%i ", detections[n].TrackID);
+			
 			if( flags & OVERLAY_CONFIDENCE )
-			{
-				char str[256];
-
-				if( (flags & OVERLAY_LABEL) && (flags & OVERLAY_CONFIDENCE) )
-				{
-					if( detections[n].Instance >= 0 )
-						sprintf(str, "%s %i %.1f%%", className, detections[n].Instance, confidence);
-					else
-						sprintf(str, "%s %.1f%%", className, confidence);
-				}
-				else
-					sprintf(str, "%.1f%%", confidence);
+				str += sprintf(str, "%.1f%%", confidence);
 
-				labels.push_back(std::pair<std::string, int2>(str, position));
-			}
-			else
+		#ifdef BATCH_TEXT
+			labels.push_back(std::pair<std::string, int2>(buffer, position));
+		#else
+			if( detections[n].TrackID >= 0 )
 			{
-				// overlay label only
-				labels.push_back(std::pair<std::string, int2>(className, position));
+				float4 color = make_float4(255,255,255,255);
+				color.w *= 1.0f - (fminf(detections[n].TrackLost, 15.0f) / 15.0f);
+				font->OverlayText(output, format, width, height, buffer, position.x, position.y, color);
 			}
+		#endif
 		}
 
+	#ifdef BATCH_TEXT
 		font->OverlayText(output, format, width, height, labels, make_float4(255,255,255,255));
+	#endif
 	}
 	
 	PROFILER_END(PROFILER_VISUALIZE);
@@ -1105,6 +1115,8 @@ uint32_t detectNet::OverlayFlagsFromStr( const char* str_user )
 			flags |= OVERLAY_LABEL;
 		else if( strcasecmp(token, "conf") == 0 || strcasecmp(token, "confidence") == 0 )
 			flags |= OVERLAY_CONFIDENCE;
+		else if( strcasecmp(token, "track") == 0 || strcasecmp(token, "tracking") == 0 )
+			flags |= OVERLAY_TRACKING;
 		else if( strcasecmp(token, "line") == 0 || strcasecmp(token, "lines") == 0 )
 			flags |= OVERLAY_LINES;
 		else if( strcasecmp(token, "default") == 0 )
diff --git a/c/detectNet.cu b/c/detectNet.cu
index 02256471f..3471c4d7a 100644
--- a/c/detectNet.cu
+++ b/c/detectNet.cu
@@ -106,7 +106,12 @@ cudaError_t launchDetectionOverlay( T* input, T* output, uint32_t width, uint32_
 		const dim3 blockDim(8, 8);
 		const dim3 gridDim(iDivUp(boxWidth,blockDim.x), iDivUp(boxHeight,blockDim.y));
 
-		gpuDetectionOverlayBox<T><<<gridDim, blockDim>>>(input, output, width, height, (int)detections[n].Left, (int)detections[n].Top, boxWidth, boxHeight, colors[detections[n].ClassID]); 
+		float4 color = colors[detections[n].ClassID];
+		
+		if( detections[n].TrackID >= 0 )
+			color.w *= 1.0f - (fminf(detections[n].TrackLost, 15.0f) / 15.0f);
+			
+		gpuDetectionOverlayBox<T><<<gridDim, blockDim>>>(input, output, width, height, (int)detections[n].Left, (int)detections[n].Top, boxWidth, boxHeight, color); 
 	}
 
 	return cudaGetLastError();
diff --git a/c/detectNet.h b/c/detectNet.h
index 8c269cb23..5ccc3b45a 100644
--- a/c/detectNet.h
+++ b/c/detectNet.h
@@ -104,7 +104,7 @@
             "  --alpha=ALPHA         overlay alpha blending value, range 0-255 (default: 120)\n"					\
 		  "  --overlay=OVERLAY     detection overlay flags (e.g. --overlay=box,labels,conf)\n"					\
 		  "                        valid combinations are:  'box', 'lines', 'labels', 'conf', 'none'\n"			\
-		  "  --profile             enable layer profiling in TensorRT\n\n"
+		  "  --profile             enable layer profiling in TensorRT\n\n"				\
 
 
 // forward declarations
@@ -128,8 +128,9 @@ class detectNet : public tensorNet
 		float Confidence;	/**< Confidence value of the detected object. */
 
 		// Tracking Info
-		int Instance;		/**< Unique tracking ID (or -1 if untracked) */
-		int TrackFrames;	/**< The number of frames the object has been positively tracked for */
+		int TrackID;		/**< Unique tracking ID (or -1 if untracked) */
+		int TrackStatus;	/**< -1 for dropped, 0 for initializing, 1 for active/valid */ 
+		int TrackFrames;	/**< The number of frames the object has been re-identified for */
 		int TrackLost;   	/**< The number of consecutive frames tracking has been lost for */
 		
 		// Bounding Box Coordinates
@@ -193,7 +194,7 @@ class detectNet : public tensorNet
 		inline bool Expand( const Detection& det )      							{ if(!Overlaps(det)) return false; Left = fminf(det.Left, Left); Top = fminf(det.Top, Top); Right = fmaxf(det.Right, Right); Bottom = fmaxf(det.Bottom, Bottom); return true; }
 
 		/**< Reset all member variables to zero */
-		inline void Reset()													{ ClassID = 0; Confidence = 0; Instance = -1; TrackFrames = 0; TrackLost = 0; Left = 0; Right = 0; Top = 0; Bottom = 0; } 								
+		inline void Reset()													{ ClassID = 0; Confidence = 0; TrackID = -1; TrackStatus = -1; TrackFrames = 0; TrackLost = 0; Left = 0; Right = 0; Top = 0; Bottom = 0; } 								
 
 		/**< Default constructor */
 		inline Detection()													{ Reset(); }
@@ -208,7 +209,8 @@ class detectNet : public tensorNet
 		OVERLAY_BOX        = (1 << 0),	/**< Overlay the object bounding boxes (filled) */
 		OVERLAY_LABEL 	    = (1 << 1),	/**< Overlay the class description labels */
 		OVERLAY_CONFIDENCE = (1 << 2),	/**< Overlay the detection confidence values */
-		OVERLAY_LINES      = (1 << 3),     /**< Overlay the bounding box lines (unfilled) */
+		OVERLAY_TRACKING   = (1 << 3),	/**< Overlay tracking information (like track ID) */
+		OVERLAY_LINES      = (1 << 4),     /**< Overlay the bounding box lines (unfilled) */
 		OVERLAY_DEFAULT    = OVERLAY_BOX|OVERLAY_LABEL|OVERLAY_CONFIDENCE, /**< The default choice of overlay */
 	};
 
diff --git a/c/trackers/objectTracker.cpp b/c/trackers/objectTracker.cpp
index 3145031ca..09af1bc5d 100644
--- a/c/trackers/objectTracker.cpp
+++ b/c/trackers/objectTracker.cpp
@@ -19,9 +19,11 @@
  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  * DEALINGS IN THE SOFTWARE.
  */
- 
+
+#include "detectNet.h" 
 #include "objectTracker.h"
 
+
 #include "objectTrackerIOU.h"
 #include "objectTrackerKLT.h"
 
@@ -29,29 +31,44 @@
 // Create
 objectTracker* objectTracker::Create( objectTracker::Type type )
 {
+	objectTracker* tracker = NULL;
+	
 	if( type == KLT )
 	{
 	#if HAS_VPI
-		return objectTrackerKLT::Create();
+		tracker = objectTrackerKLT::Create();
 	#else
 		LogError(LOG_TRACKER "couldn't create KLT tracker (not built with VPI enabled)\n");
-		return NULL;
 	#endif
 	}
 	else if( type == IOU )
 	{
-		return objectTrackerIOU::Create();
+		tracker = objectTrackerIOU::Create();
 	}
 	
-	return NULL;
+	if( !tracker )
+		return NULL;
+	
+	if( !tracker->Init() )
+	{
+		delete tracker;
+		return NULL;
+	}
+	
+	return tracker;
 }
 
 
 // Create
 objectTracker* objectTracker::Create( const commandLine& cmdLine )
 {
-	const char* str = cmdLine.GetString("tracker", cmdLine.GetString("tracking"));
-	const Type type = TypeFromStr(str);
+	Type type = IOU;
+	
+	const bool useDefault = cmdLine.GetFlag("tracking");
+	const char* typeStr = cmdLine.GetString("tracker", cmdLine.GetString("tracking"));
+	
+	if( !useDefault )
+		type = TypeFromStr(typeStr);
 	
 	if( type == KLT )
 	{
@@ -68,8 +85,8 @@ objectTracker* objectTracker::Create( const commandLine& cmdLine )
 	}
 	else
 	{
-		if( str != NULL )
-			LogError(LOG_TRACKER "tried to create invalid object tracker type:  %s\n", str);
+		if( typeStr != NULL )
+			LogError(LOG_TRACKER "tried to create invalid object tracker type:  %s\n", typeStr);
 	}
 	
 	return NULL;
diff --git a/c/trackers/objectTracker.h b/c/trackers/objectTracker.h
index c74903e78..9b10f7bc8 100644
--- a/c/trackers/objectTracker.h
+++ b/c/trackers/objectTracker.h
@@ -28,12 +28,23 @@
 
 
 /**
- * Tracker logging prefix
+ * Standard command-line options able to be passed to detectNet::Create()
+ * @ingroup objectTracker
+ */
+#define OBJECT_TRACKER_USAGE_STRING  "objectTracker arguments: \n" 	\
+		  "  --tracking               flag to enable default tracker (IOU)\n"									\
+		  "  --tracker=TRACKER        enable tracking with 'IOU' or 'KLT'\n"									\
+		  "  --tracker-min-frames=N   the number of re-identified frames for a track to be considered valid (default: 3)\n" \
+		  "  --tracker-lost-frames=N  number of consecutive lost frames before a track is removed (default: 15)\n"  \
+		  "  --tracker-overlap=N      how much IOU overlap is required for a bounding box to be matched (default: 0.5)\n\n" \
+	
+/**
+ * Object tracker logging prefix
  * @ingroup objectTracker
  */
 #define LOG_TRACKER "[tracker] "
 
-
+  
 /**
  * Object tracker interface
  * @ingroup objectTracker
@@ -66,6 +77,11 @@ class objectTracker
 	 */
 	static objectTracker* Create( const commandLine& cmdLine );
 	
+	/**
+	 * Init (optional)
+	 */
+	virtual bool Init()					{ return true; }
+	
 	/**
 	 * Process
 	 */
@@ -81,6 +97,11 @@ class objectTracker
 	 */
 	virtual Type GetType() const = 0;
 	
+	/**
+	 * Usage string for command line arguments to Create()
+	 */
+	static inline const char* Usage() 		{ return OBJECT_TRACKER_USAGE_STRING; }
+
 	/**
 	 * Convert a Type enum to string.
 	 */
diff --git a/c/trackers/objectTrackerIOU.cpp b/c/trackers/objectTrackerIOU.cpp
index 67073a14f..b9a8cd5cb 100644
--- a/c/trackers/objectTrackerIOU.cpp
+++ b/c/trackers/objectTrackerIOU.cpp
@@ -24,10 +24,15 @@
 
 
 // constructor
-objectTrackerIOU::objectTrackerIOU()
+objectTrackerIOU::objectTrackerIOU( uint32_t minFrames, uint32_t dropFrames, float overlapThreshold )
 {
+	mIDCount = 0;
 	mFrameCount = 0;
-	mInstanceCount = 0;
+	
+	mMinFrames = minFrames;
+	mDropFrames = dropFrames;
+	
+	mOverlapThreshold = overlapThreshold;
 	
 	mTracks.reserve(128);
 }
@@ -39,10 +44,11 @@ objectTrackerIOU::~objectTrackerIOU()
 
 }
 
+
 // Create
-objectTrackerIOU* objectTrackerIOU::Create()
+objectTrackerIOU* objectTrackerIOU::Create( uint32_t minFrames, uint32_t dropFrames, float overlapThreshold )
 {
-	objectTrackerIOU* tracker = new objectTrackerIOU();
+	objectTrackerIOU* tracker = new objectTrackerIOU(minFrames, dropFrames, overlapThreshold);
 	
 	if( !tracker )
 		return NULL;
@@ -54,7 +60,9 @@ objectTrackerIOU* objectTrackerIOU::Create()
 // Create
 objectTrackerIOU* objectTrackerIOU::Create( const commandLine& cmdLine )
 {
-	return Create();
+	return Create(cmdLine.GetUnsignedInt("tracker-min-frames", OBJECT_TRACKER_DEFAULT_MIN_FRAMES),
+			    cmdLine.GetUnsignedInt("tracker-drop-frames", OBJECT_TRACKER_DEFAULT_DROP_FRAMES),
+			    cmdLine.GetFloat("tracker-overlap", OBJECT_TRACKER_DEFAULT_OVERLAP_THRESHOLD));
 }
 
 
@@ -73,7 +81,7 @@ int findBestIOU( const detectNet::Detection& track, detectNet::Detection* detect
 	
 	for( int n=0; n < numDetections; n++ )
 	{
-		if( detections[n].Instance >= 0 )
+		if( detections[n].TrackID >= 0 )
 			continue; // this bbox is already a match for another track
 		
 		if( detections[n].ClassID != track.ClassID )
@@ -91,44 +99,49 @@ int findBestIOU( const detectNet::Detection& track, detectNet::Detection* detect
 	return maxDetection;
 }
 		
-		
+
 // Process
 int objectTrackerIOU::Process( void* input, uint32_t width, uint32_t height, imageFormat format, detectNet::Detection* detections, int numDetections )
 {
 	// update active tracks
 	for( int n=0; n < mTracks.size(); n++ )
 	{
-		const int bestMatch = findBestIOU(mTracks[n], detections, numDetections);
+		const int bestMatch = findBestIOU(mTracks[n], detections, numDetections, mOverlapThreshold);
 		
 		if( bestMatch >= 0 )
 		{
-			detections[bestMatch].Instance = mTracks[n].Instance;
+			detections[bestMatch].TrackID = (mTracks[n].TrackFrames == mMinFrames) ? mIDCount++ : mTracks[n].TrackID;
 			detections[bestMatch].TrackFrames = mTracks[n].TrackFrames + 1;
+			detections[bestMatch].TrackStatus = (detections[bestMatch].TrackFrames >= mMinFrames) ? 1 : 0;
 			detections[bestMatch].TrackLost = 0;
 			
 			mTracks[n] = detections[bestMatch];
 			
-			LogVerbose(LOG_TRACKER "updated track -> instance=%i class=%u frames=%i\n", detections[n].Instance, detections[n].ClassID, detections[n].TrackFrames);
+			LogVerbose(LOG_TRACKER "updated track %i -> class=%u status=%i frames=%i\n", detections[n].TrackID, detections[n].ClassID, detections[n].TrackStatus, detections[n].TrackFrames);
 		}
 		else
 		{
 			mTracks[n].TrackLost++;
+			
+			if( mTracks[n].TrackLost >= mDropFrames )
+				mTracks[n].TrackStatus = -1;
 		}
 	}
 	
 	// add new tracks
 	for( int n=0; n < numDetections; n++ )
 	{
-		if( detections[n].Instance >= 0 )
+		if( detections[n].TrackID >= 0 )
 			continue;
 		
-		detections[n].Instance = mInstanceCount++;
+		detections[n].TrackID = -1;
+		detections[n].TrackStatus = 0;
 		detections[n].TrackFrames = 0;
 		detections[n].TrackLost = 0;
 		
 		mTracks.push_back(detections[n]);
 		
-		LogVerbose(LOG_TRACKER "added track -> instance=%i class=%u\n", detections[n].Instance, detections[n].ClassID);
+		LogVerbose(LOG_TRACKER "added track %i -> class=%u\n", detections[n].TrackID, detections[n].ClassID);
 	}
 	
 	// add valid tracks to the output array
@@ -136,16 +149,16 @@ int objectTrackerIOU::Process( void* input, uint32_t width, uint32_t height, ima
 	
 	for( int n=0; n < mTracks.size(); n++ )
 	{
-		if( mTracks[n].TrackFrames >= 3 )
+		if( mTracks[n].TrackFrames >= mMinFrames )
 			detections[numDetections++] = mTracks[n];
 	}
 	
 	// remove dropped tracks
 	for( auto iter = mTracks.begin(); iter != mTracks.end(); )
 	{
-		if( iter->TrackLost > 15 )
+		if( iter->TrackStatus < 0 )
 		{
-			LogVerbose(LOG_TRACKER "dropped track -> instance=%i class=%u frames=%i\n", iter->Instance, iter->ClassID, iter->TrackFrames);
+			LogVerbose(LOG_TRACKER "dropped track %i -> class=%u frames=%i\n", iter->TrackID, iter->ClassID, iter->TrackFrames);
 			iter = mTracks.erase(iter);
 		}
 		else
diff --git a/c/trackers/objectTrackerIOU.h b/c/trackers/objectTrackerIOU.h
index 702278159..8ab9404ad 100644
--- a/c/trackers/objectTrackerIOU.h
+++ b/c/trackers/objectTrackerIOU.h
@@ -27,10 +27,33 @@
 #include "objectTracker.h"
 
 
+/**
+ * The number of re-identified frames before establishing a track
+ * @ingroup objectTracker
+ */
+#define OBJECT_TRACKER_DEFAULT_MIN_FRAMES 3
+
+/**
+ * The number of consecutive lost frames after which a track is removed
+ * @ingroup objectTracker
+ */
+#define OBJECT_TRACKER_DEFAULT_DROP_FRAMES 15
+
+/**
+ * How much IOU overlap is required for a bounding box to be matched
+ */
+#define OBJECT_TRACKER_DEFAULT_OVERLAP_THRESHOLD 0.5
+
+
 /**
  * Object tracker using Intersection-Over-Union (IOU)
+ *
  * "High-Speed Tracking-by-Detection Without Using Image Information"
  * http://elvera.nue.tu-berlin.de/files/1517Bochinski2017.pdf
+ *
+ * This tracker essentially performs temporal clustering of bounding boxes
+ * without using visual information, hence it is very fast but low accuracy.
+ *
  * @ingroup objectTracker
  */
 class objectTrackerIOU : public objectTracker
@@ -38,8 +61,12 @@ class objectTrackerIOU : public objectTracker
 public:
 	/**
 	 * Create a new object tracker.
+	 * @param minFrames the number of re-identified frames before before establishing a track
+	 * @param dropFrames the number of consecutive lost frames after which a track is removed
 	 */
-	static objectTrackerIOU* Create();
+	static objectTrackerIOU* Create( uint32_t minFrames=OBJECT_TRACKER_DEFAULT_MIN_FRAMES,
+							   uint32_t dropFrames=OBJECT_TRACKER_DEFAULT_DROP_FRAMES,
+							   float overlapThreshold=OBJECT_TRACKER_DEFAULT_OVERLAP_THRESHOLD );
 	
 	/**
 	 * Create a new object tracker by parsing the command line.
@@ -57,21 +84,56 @@ class objectTrackerIOU : public objectTracker
 	~objectTrackerIOU();
 	
 	/**
-	 * GetType
+	 * The number of re-identified frames before before establishing a track
+	 */
+	inline uint32_t GetMinFrames() const					{ return mMinFrames; }
+	
+	/**
+	 * Set the number of re-identified frames before before establishing a track
 	 */
-	inline virtual Type GetType() const	{ return IOU; }
+	inline void SetMinFrames( uint32_t frames )				{ mMinFrames = frames; }
 	
 	/**
-	 * Process
+	 * The number of consecutive lost frames after which a track is removed
+	 */
+	inline uint32_t GetDropFrames() const					{ return mDropFrames; }
+	
+	/**
+	 * Set the number of re-identified frames before before establishing a track
+	 */
+	inline void SetDropFrames( uint32_t frames )				{ mDropFrames = frames; }
+	
+	/**
+	 * How much IOU overlap is required for a bounding box to be matched
+	 */
+	inline float GetOverlapThreshold() const				{ return mOverlapThreshold; }
+	
+	/**
+	 * Set how much IOU overlap is required for a bounding box to be matched
+	 */
+	inline void SetOverlapThreshold( float threshold )		{ mOverlapThreshold = threshold; }
+	
+	/**
+	 * @see objectTracker::GetType
+	 */
+	inline virtual Type GetType() const					{ return IOU; }
+	
+	/**
+	 * @see objectTracker::Process
 	 */
 	virtual int Process( void* image, uint32_t width, uint32_t height, imageFormat format, detectNet::Detection* detections, int numDetections );
 	
 protected:
-	objectTrackerIOU();
+	objectTrackerIOU( uint32_t minFrames, uint32_t dropFrames, float overlapThreshold );
 	
+	uint32_t mIDCount;
 	uint64_t mFrameCount;
-	uint32_t mInstanceCount;
 	
+	uint32_t mMinFrames;
+	uint32_t mDropFrames;
+	
+	float mOverlapThreshold;
+
 	std::vector<detectNet::Detection> mTracks;
 };
 
diff --git a/examples/detectnet/detectnet.cpp b/examples/detectnet/detectnet.cpp
index 8f08ce15e..df48be1ce 100644
--- a/examples/detectnet/detectnet.cpp
+++ b/examples/detectnet/detectnet.cpp
@@ -24,6 +24,8 @@
 #include "videoOutput.h"
 
 #include "detectNet.h"
+#include "objectTracker.h"
+
 
 #include <signal.h>
 
@@ -49,14 +51,15 @@ void sig_handler(int signo)
 int usage()
 {
 	printf("usage: detectnet [--help] [--network=NETWORK] [--threshold=THRESHOLD] ...\n");
-	printf("                 input_URI [output_URI]\n\n");
+	printf("                 input [output]\n\n");
 	printf("Locate objects in a video/image stream using an object detection DNN.\n");
 	printf("See below for additional arguments that may not be shown above.\n\n");
 	printf("positional arguments:\n");
-	printf("    input_URI       resource URI of input stream  (see videoSource below)\n");
-	printf("    output_URI      resource URI of output stream (see videoOutput below)\n\n");
+	printf("    input           resource URI of input stream  (see videoSource below)\n");
+	printf("    output          resource URI of output stream (see videoOutput below)\n\n");
 
 	printf("%s", detectNet::Usage());
+	printf("%s", objectTracker::Usage());
 	printf("%s", videoSource::Usage());
 	printf("%s", videoOutput::Usage());
 	printf("%s", Log::Usage());
@@ -150,8 +153,8 @@ int main( int argc, char** argv )
 				LogVerbose("\ndetected obj %i  class #%u (%s)  confidence=%f\n", n, detections[n].ClassID, net->GetClassDesc(detections[n].ClassID), detections[n].Confidence);
 				LogVerbose("bounding box %i  (%.2f, %.2f)  (%.2f, %.2f)  w=%.2f  h=%.2f\n", n, detections[n].Left, detections[n].Top, detections[n].Right, detections[n].Bottom, detections[n].Width(), detections[n].Height()); 
 			
-				if( detections[n].Instance >= 0 ) // is this a tracked object?
-					LogVerbose("tracking instance %i  frames=%i  lost=%i\n", detections[n].Instance, detections[n].TrackFrames, detections[n].TrackLost);
+				if( detections[n].TrackID >= 0 ) // is this a tracked object?
+					LogVerbose("tracking  ID %i  status=%i  frames=%i  lost=%i\n", detections[n].TrackID, detections[n].TrackStatus, detections[n].TrackFrames, detections[n].TrackLost);
 			}
 		}	
 
diff --git a/examples/object-tracker/object-tracker.cpp b/examples/object-tracker/object-tracker.cpp
index 8ab98883e..53c607968 100644
--- a/examples/object-tracker/object-tracker.cpp
+++ b/examples/object-tracker/object-tracker.cpp
@@ -51,6 +51,7 @@ int usage()
 	printf("    output_URI      resource URI of output stream (see videoOutput below)\n\n");
 
 	printf("%s", detectNet::Usage());
+	printf("%s", objectTracker::Usage());
 	printf("%s", videoSource::Usage());
 	printf("%s", videoOutput::Usage());
 	printf("%s", Log::Usage());
@@ -167,7 +168,7 @@ int main( int argc, char** argv )
 		
 			for( int n=0; n < numTracks; n++ )
 			{
-				LogVerbose("tracked  obj %i  class #%u (%s)  confidence=%f  instance=%i  frames=%i  lost=%i\n", n, detections[n].ClassID, net->GetClassDesc(detections[n].ClassID), detections[n].Confidence, detections[n].Instance, detections[n].TrackFrames, detections[n].TrackLost);
+				LogVerbose("tracked  obj %i  class #%u (%s)  confidence=%f  instance=%i  frames=%i  lost=%i\n", n, detections[n].ClassID, net->GetClassDesc(detections[n].ClassID), detections[n].Confidence, detections[n].TrackID, detections[n].TrackFrames, detections[n].TrackLost);
 				LogVerbose("bounding box %i  (%f, %f)  (%f, %f)  w=%f  h=%f\n", n, detections[n].Left, detections[n].Top, detections[n].Right, detections[n].Bottom, detections[n].Width(), detections[n].Height()); 
 			}
 		}
diff --git a/python/bindings/PyDetectNet.cpp b/python/bindings/PyDetectNet.cpp
index 981f78776..65d295f7f 100644
--- a/python/bindings/PyDetectNet.cpp
+++ b/python/bindings/PyDetectNet.cpp
@@ -46,12 +46,12 @@ typedef struct {
 				  "    Center (x,y) coordinate of bounding box\n\n" \
 				  "ClassID\n" \
 				  "    Class index of the detected object\n\n" \
+				  "TrackID\n" \
+				  "    Unique tracking ID (or -1 if untracked)\n\n" \
 				  "Confidence\n" \
 				  "    Confidence value of the detected object\n\n" \
 				  "Height\n" \
 				  "    Height of bounding box\n\n" \
-				  "Instance\n" \
-				  "    Instance index of the detected object\n\n" \
 				  "Left\n" \
 				  "    Left bounding box coordinate\n\n" \
 				  "Right\n" \
@@ -136,15 +136,16 @@ static PyObject* PyDetection_ToString( PyDetection_Object* self )
 	// format string
 	char str[4096];
 
-	if( self->det.Instance >= 0 )
+	if( self->det.TrackID >= 0 )
 	{
 		sprintf(str, 
 			   "<detectNet.Detection object>\n"
-			   "   -- ClassID:      %i\n"
-			   "   -- Confidence:   %g\n"
-			   "   -- Instance:     %i\n"
-			   "   -- Track Frames: %i\n"
-			   "   -- Track Lost:   %i\n"
+			   "   -- Confidence:  %g\n"
+			   "   -- ClassID:     %i\n"
+			   "   -- TrackID:     %i\n"
+			   "   -- TrackStatus: %i\n"
+			   "   -- TrackFrames: %i\n"
+			   "   -- TrackLost:   %i\n"
 			   "   -- Left:    %g\n"
 			   "   -- Top:     %g\n"
 			   "   -- Right:   %g\n"
@@ -153,8 +154,8 @@ static PyObject* PyDetection_ToString( PyDetection_Object* self )
 			   "   -- Height:  %g\n"
 			   "   -- Area:    %g\n"
 			   "   -- Center:  (%g, %g)",
-			   self->det.ClassID, self->det.Confidence, 
-			   self->det.Instance, self->det.TrackFrames, self->det.TrackLost,
+			   self->det.Confidence, self->det.ClassID,  
+			   self->det.TrackID, self->det.TrackStatus, self->det.TrackFrames, self->det.TrackLost,
 			   self->det.Left, self->det.Top, self->det.Right, self->det.Bottom,
 			   self->det.Width(), self->det.Height(), self->det.Area(), cx, cy);
 	}
@@ -162,8 +163,8 @@ static PyObject* PyDetection_ToString( PyDetection_Object* self )
 	{
 		sprintf(str, 
 			   "<detectNet.Detection object>\n"
-			   "   -- ClassID: %i\n"
 			   "   -- Confidence: %g\n"
+			   "   -- ClassID: %i\n"
 			   "   -- Left:    %g\n"
 			   "   -- Top:     %g\n"
 			   "   -- Right:   %g\n"
@@ -172,7 +173,7 @@ static PyObject* PyDetection_ToString( PyDetection_Object* self )
 			   "   -- Height:  %g\n"
 			   "   -- Area:    %g\n"
 			   "   -- Center:  (%g, %g)",
-			   self->det.ClassID, self->det.Confidence, 
+			   self->det.Confidence, self->det.ClassID,  
 			   self->det.Left, self->det.Top, self->det.Right, self->det.Bottom,
 			   self->det.Width(), self->det.Height(), self->det.Area(), cx, cy);
 	}
@@ -203,18 +204,18 @@ static PyObject* PyDetection_Contains( PyDetection_Object* self, PyObject *args,
 }
 
 
-// GetInstance
-static PyObject* PyDetection_GetInstance( PyDetection_Object* self, void* closure )
+// GetTrackID
+static PyObject* PyDetection_GetTrackID( PyDetection_Object* self, void* closure )
 {
-	return PYLONG_FROM_LONG(self->det.Instance);
+	return PYLONG_FROM_LONG(self->det.TrackID);
 }
 
-// SetInstance
-static int PyDetection_SetInstance( PyDetection_Object* self, PyObject* value, void* closure )
+// SetTrackID
+static int PyDetection_SetTrackID( PyDetection_Object* self, PyObject* value, void* closure )
 {
 	if( !value )
 	{
-		PyErr_SetString(PyExc_TypeError, LOG_PY_INFERENCE "Not permitted to delete detectNet.Detection.Instance attribute");
+		PyErr_SetString(PyExc_TypeError, LOG_PY_INFERENCE "Not permitted to delete detectNet.Detection.TrackID attribute");
 		return -1;
 	}
 
@@ -223,7 +224,7 @@ static int PyDetection_SetInstance( PyDetection_Object* self, PyObject* value, v
 	if( PyErr_Occurred() != NULL )
 		return -1;
 
-	self->det.Instance = arg;
+	self->det.TrackID = arg;
 	return 0;
 }
 
@@ -441,8 +442,9 @@ static PyObject* PyDetection_GetROI( PyDetection_Object* self, void* closure )
 
 static PyGetSetDef pyDetection_GetSet[] = 
 {
-	{ "Instance", (getter)PyDetection_GetInstance, (setter)PyDetection_SetInstance, "Instance index of the detected object", NULL},
 	{ "ClassID", (getter)PyDetection_GetClassID, (setter)PyDetection_SetClassID, "Class index of the detected object", NULL},
+	{ "TrackID", (getter)PyDetection_GetTrackID, (setter)PyDetection_SetTrackID, "Unique tracking ID (-1 if untracked)", NULL},
+	{ "Instance", (getter)PyDetection_GetTrackID, (setter)PyDetection_SetTrackID, "Unique tracking ID (-1 if untracked)", NULL}, // legacy
 	{ "Confidence", (getter)PyDetection_GetConfidence, (setter)PyDetection_SetConfidence, "Confidence value of the detected object", NULL},
 	{ "Left", (getter)PyDetection_GetLeft, (setter)PyDetection_SetLeft, "Left bounding box coordinate", NULL},
 	{ "Right", (getter)PyDetection_GetRight, (setter)PyDetection_SetRight, "Right bounding box coordinate", NULL},