Using multiple instances of OCR and state recognizer for multiple threads

src/openalpr/alpr_impl.cpp

@@ -26,8 +26,17 @@ AlprImpl::AlprImpl(const std::string country, const std::string runtimeDir)
 {
   config = new Config(country, runtimeDir);
   plateDetector = new RegionDetector(config);
-  stateIdentifier = new StateIdentifier(config);
+  
-  ocr = new OCR(config);
+  int numThreads = getNumThreads();
+  
+  for (int i = 0; i < numThreads; i++)
+  {
+    StateIdentifier* stateIdentifier = new StateIdentifier(config);
+    OCR* ocr = new OCR(config);
+    
+    stateIdentifiers.push_back(stateIdentifier);
+    ocrs.push_back(ocr);
+  }
   
   setNumThreads(0);
   
@@ -68,10 +77,28 @@ AlprImpl::~AlprImpl()
 {
   delete config;
   delete plateDetector;
-  delete stateIdentifier;
+  
-  delete ocr;
+  for (int i = 0; i < stateIdentifiers.size(); i++)
+  {
+    delete stateIdentifiers[i];	
+    delete ocrs[i];
+  }
+  
+  stateIdentifiers.clear();
+  ocrs.clear();
 }
 
+int AlprImpl::getNumThreads()
+{
+  // Get the number of threads specified and make sure the value is sane (cannot be greater than CPU cores or less than 1)
+  int numThreads = config->multithreading_cores;
+  if (numThreads > tthread::thread::hardware_concurrency())
+    numThreads = tthread::thread::hardware_concurrency();
+  if (numThreads <= 0)
+    numThreads = 1;
+  
+  return numThreads;
+}
 
 std::vector<AlprResult> AlprImpl::recognize(cv::Mat img)
 {
@@ -83,15 +110,11 @@ std::vector<AlprResult> AlprImpl::recognize(cv::Mat img)
   vector<Rect> plateRegions = plateDetector->detect(img);
 
   // Get the number of threads specified and make sure the value is sane (cannot be greater than CPU cores or less than 1)
-  int numThreads = config->multithreading_cores;
+  int numThreads = getNumThreads();
-  if (numThreads > tthread::thread::hardware_concurrency())
-    numThreads = tthread::thread::hardware_concurrency();
-  if (numThreads <= 0)
-    numThreads = 1;
 
   
   PlateDispatcher dispatcher(plateRegions, &img, 
-			     config, stateIdentifier, ocr, 
+			     config, stateIdentifiers, ocrs, 
 			     topN, detectRegion, defaultRegion);
     
   // Spawn n threads to process all of the candidate regions and recognize
@@ -141,13 +164,28 @@ std::vector<AlprResult> AlprImpl::recognize(cv::Mat img)
 void plateAnalysisThread(void* arg)
 {
   PlateDispatcher* dispatcher = (PlateDispatcher*) arg;
+  
+  timespec syncstarttime;
+  getTime(&syncstarttime);
+  
+  int threadID = dispatcher->getUniqueThreadId();
+  Mat img = dispatcher->getImageCopy();
+      
   if (dispatcher->config->debugGeneral)
     cout << "Thread: " << tthread::this_thread::get_id() << " Initialized" << endl;
+
+  if (dispatcher->config->debugTiming)
+  {
+    timespec syncendtime;
+    getTime(&syncendtime);
+    cout << "Thread: " << tthread::this_thread::get_id() << " Synchronized initialization time in " << diffclock(syncstarttime, syncendtime) << "ms." << endl;
+  }
   
   int loop_count = 0;
   while (true)
   {
     
+    
     if (dispatcher->hasPlate() == false)
       break;
     
@@ -158,7 +196,7 @@ void plateAnalysisThread(void* arg)
     // Get a single plate region from the queue
     Rect plateRegion = dispatcher->nextPlate();
     
-    Mat img = dispatcher->getImageCopy();
+    
 
   
     // Parallel section
@@ -166,6 +204,9 @@ void plateAnalysisThread(void* arg)
       timespec platestarttime;
       getTime(&platestarttime);
       
+      StateIdentifier* stateIdentifier = dispatcher->stateIdentifiers[threadID];
+      OCR* ocr = dispatcher->ocrs[threadID];
+      
       LicensePlateCandidate lp(img, plateRegion, dispatcher->config);
       
       lp.recognize();
@@ -186,7 +227,7 @@ void plateAnalysisThread(void* arg)
 	if (dispatcher->detectRegion)
 	{
 	  char statecode[4];
-	  plateResult.regionConfidence = dispatcher->stateIdentifier->recognize(img, plateRegion, statecode);
+	  plateResult.regionConfidence = stateIdentifier->recognize(img, plateRegion, statecode);
 	  if (plateResult.regionConfidence > 0)
 	  {
 	    plateResult.region = statecode;
@@ -194,12 +235,12 @@ void plateAnalysisThread(void* arg)
 	} 
     
     
-	dispatcher->ocr->performOCR(lp.charSegmenter->getThresholds(), lp.charSegmenter->characters);
+	ocr->performOCR(lp.charSegmenter->getThresholds(), lp.charSegmenter->characters);
 	
-	dispatcher->ocr->postProcessor->analyze(plateResult.region, dispatcher->topN);
+	ocr->postProcessor->analyze(plateResult.region, dispatcher->topN);
 
 	//plateResult.characters = ocr->postProcessor->bestChars;
-	const vector<PPResult> ppResults = dispatcher->ocr->postProcessor->getResults();
+	const vector<PPResult> ppResults = ocr->postProcessor->getResults();
 	
 	int bestPlateIndex = 0;
 	

src/openalpr/alpr_impl.h

@@ -63,15 +63,17 @@ class AlprImpl
     
   private:
     
+    int getNumThreads();
+    cJSON* createJsonObj(const AlprResult* result);
+    
     RegionDetector* plateDetector;
-    StateIdentifier* stateIdentifier;
+    vector<StateIdentifier*> stateIdentifiers;
-    OCR* ocr;
+    vector<OCR*> ocrs;
   
     int topN;
     bool detectRegion;
     std::string defaultRegion;
     
-    cJSON* createJsonObj(const AlprResult* result);
     
     
 };
@@ -81,19 +83,21 @@ class PlateDispatcher
   public:
     PlateDispatcher(vector<Rect> plateRegions, cv::Mat* image, 
 		    Config* config,
-		    StateIdentifier* stateIdentifier,
+		    vector<StateIdentifier*> stateIdentifiers,
-		    OCR* ocr,
+		    vector<OCR*> ocrs,
 		    int topN, bool detectRegion, std::string defaultRegion) 
     {
       this->plateRegions = plateRegions;
       this->frame = image;
       
       this->config = config;
-      this->stateIdentifier = stateIdentifier;
+      this->stateIdentifiers = stateIdentifiers;
-      this->ocr = ocr;
+      this->ocrs = ocrs;
       this->topN = topN;
       this->detectRegion = detectRegion;
       this->defaultRegion = defaultRegion;
+      
+      this->threadCounter = 0;
     }
 
     cv::Mat getImageCopy()
@@ -105,6 +109,13 @@ class PlateDispatcher
       
       return img;
     }
+    
+    int getUniqueThreadId()
+    {
+      tthread::lock_guard<tthread::mutex> guard(mMutex);
+      
+      return threadCounter++;
+    }
 
     bool hasPlate()
     {
@@ -136,8 +147,8 @@ class PlateDispatcher
     }
     
 
-    StateIdentifier* stateIdentifier;
+    vector<StateIdentifier*> stateIdentifiers;
-    OCR* ocr;
+    vector<OCR*> ocrs;
     Config* config;
   
     int topN;
@@ -146,6 +157,7 @@ class PlateDispatcher
     
   private:
     
+    int threadCounter;
     tthread::mutex mMutex;
     cv::Mat* frame;
     vector<Rect> plateRegions;