Changed Linux timestamp behavior. Explicitly using CLOCK_MONOTONIC_RAW and CLOCK_REALTIME

src/daemon.cpp

@@ -286,7 +286,7 @@ void streamRecognitionThread(void* arg)
     {
       
       timespec startTime;
-      getTime(&startTime);
+      getTimeMonotonic(&startTime);
       
       std::vector<AlprRegionOfInterest> regionsOfInterest;
       regionsOfInterest.push_back(AlprRegionOfInterest(0,0, latestFrame.cols, latestFrame.rows));
@@ -294,7 +294,7 @@ void streamRecognitionThread(void* arg)
       AlprResults results = alpr.recognize(latestFrame.data, latestFrame.elemSize(), latestFrame.cols, latestFrame.rows, regionsOfInterest);
       
       timespec endTime;
-      getTime(&endTime);
+      getTimeMonotonic(&endTime);
       double totalProcessingTime = diffclock(startTime, endTime);
       
       if (tdata->clock_on)
@@ -304,10 +304,9 @@ void streamRecognitionThread(void* arg)
       
       if (results.plates.size() > 0)
       {
-        long epoch_time = getEpochTime();
         
         std::stringstream uuid_ss;
-        uuid_ss << tdata->site_id << "-cam" << tdata->camera_id << "-" << epoch_time;
+        uuid_ss << tdata->site_id << "-cam" << tdata->camera_id << "-" << getEpochTimeMs();
 	std::string uuid = uuid_ss.str();
         
 	// Save the image to disk (using the UUID)

src/main.cpp

@@ -275,7 +275,7 @@ bool detectandshow( Alpr* alpr, cv::Mat frame, std::string region, bool writeJso
 {
 
   timespec startTime;
-  getTime(&startTime);
+  getTimeMonotonic(&startTime);
 
   std::vector<AlprRegionOfInterest> regionsOfInterest;
   regionsOfInterest.push_back(AlprRegionOfInterest(0,0, frame.cols, frame.rows));
@@ -283,7 +283,7 @@ bool detectandshow( Alpr* alpr, cv::Mat frame, std::string region, bool writeJso
   AlprResults results = alpr->recognize(frame.data, frame.elemSize(), frame.cols, frame.rows, regionsOfInterest );
 
   timespec endTime;
-  getTime(&endTime);
+  getTimeMonotonic(&endTime);
   double totalProcessingTime = diffclock(startTime, endTime);
   if (measureProcessingTime)
     std::cout << "Total Time to process image: " << totalProcessingTime << "ms." << std::endl;

src/misc_utilities/benchmarks/benchmark.cpp

@@ -187,18 +187,18 @@ int main( int argc, const char** argv )
         string fullpath = inDir + "/" + files[i];
         frame = imread( fullpath.c_str() );
 
-        getTime(&startTime);
+        getTimeMonotonic(&startTime);
         vector<Rect> regionsOfInterest;
         regionsOfInterest.push_back(Rect(0, 0, frame.cols, frame.rows));
         alpr.recognize(frame, regionsOfInterest);
-        getTime(&endTime);
+        getTimeMonotonic(&endTime);
         double endToEndTime = diffclock(startTime, endTime);
         cout << " -- End to End recognition time: " << endToEndTime << "ms." << endl;
         endToEndTimes.push_back(endToEndTime);
 
-        getTime(&startTime);
+        getTimeMonotonic(&startTime);
         vector<PlateRegion> regions = plateDetector->detect(frame);
-        getTime(&endTime);
+        getTimeMonotonic(&endTime);
 
         double regionDetectionTime = diffclock(startTime, endTime);
         cout << " -- Region detection time: " << regionDetectionTime << "ms." << endl;
@@ -209,18 +209,18 @@ int main( int argc, const char** argv )
 	  
 	  PipelineData pipeline_data(frame, regions[z].rect, &config);
 	  
-          getTime(&startTime);
+          getTimeMonotonic(&startTime);
 	  
           stateIdentifier.recognize(&pipeline_data);
-          getTime(&endTime);
+          getTimeMonotonic(&endTime);
           double stateidTime = diffclock(startTime, endTime);
           cout << "\tRegion " << z << ": State ID time: " << stateidTime << "ms." << endl;
           stateIdTimes.push_back(stateidTime);
 
-          getTime(&startTime);
+          getTimeMonotonic(&startTime);
           LicensePlateCandidate lp(&pipeline_data);
           lp.recognize();
-          getTime(&endTime);
+          getTimeMonotonic(&endTime);
           double analysisTime = diffclock(startTime, endTime);
           cout << "\tRegion " << z << ": Analysis time: " << analysisTime << "ms." << endl;
 
@@ -228,16 +228,16 @@ int main( int argc, const char** argv )
           {
             lpAnalysisPositiveTimes.push_back(analysisTime);
 
-            getTime(&startTime);
+            getTimeMonotonic(&startTime);
             ocr.performOCR(&pipeline_data);
-            getTime(&endTime);
+            getTimeMonotonic(&endTime);
             double ocrTime = diffclock(startTime, endTime);
             cout << "\tRegion " << z << ": OCR time: " << ocrTime << "ms." << endl;
             ocrTimes.push_back(ocrTime);
 
-            getTime(&startTime);
+            getTimeMonotonic(&startTime);
             ocr.postProcessor.analyze("", 25);
-            getTime(&endTime);
+            getTimeMonotonic(&endTime);
             double postProcessTime = diffclock(startTime, endTime);
             cout << "\tRegion " << z << ": PostProcess time: " << postProcessTime << "ms." << endl;
             postProcessTimes.push_back(postProcessTime);

src/openalpr/alpr.cpp

@@ -55,7 +55,7 @@ namespace alpr
     {
       std::cerr << "file does not exist: " << filepath << std::endl;
       AlprResults emptyResults;
-      emptyResults.epoch_time = getEpochTime();
+      emptyResults.epoch_time = getEpochTimeMs();
       emptyResults.img_width = 0;
       emptyResults.img_height = 0;
       emptyResults.total_processing_time_ms = 0;

src/openalpr/alpr_impl.cpp

@@ -72,12 +72,12 @@ namespace alpr
   AlprFullDetails AlprImpl::recognizeFullDetails(cv::Mat img, std::vector<cv::Rect> regionsOfInterest)
   {
     timespec startTime;
-    getTime(&startTime);
+    getTimeMonotonic(&startTime);
 
 
     AlprFullDetails response;
 
-    response.results.epoch_time = getEpochTime();
+    response.results.epoch_time = getEpochTimeMs();
     response.results.img_width = img.cols;
     response.results.img_height = img.rows;
 
@@ -126,7 +126,7 @@ namespace alpr
       PipelineData pipeline_data(img, plateRegion.rect, config);
 
       timespec platestarttime;
-      getTime(&platestarttime);
+      getTimeMonotonic(&platestarttime);
 
       LicensePlateCandidate lp(&pipeline_data);
 
@@ -196,7 +196,7 @@ namespace alpr
         }
 
         timespec plateEndTime;
-        getTime(&plateEndTime);
+        getTimeMonotonic(&plateEndTime);
         plateResult.processing_time_ms = diffclock(platestarttime, plateEndTime);
 
         if (plateResult.topNPlates.size() > 0)
@@ -222,7 +222,7 @@ namespace alpr
     }
 
     timespec endTime;
-    getTime(&endTime);
+    getTimeMonotonic(&endTime);
     response.results.total_processing_time_ms = diffclock(startTime, endTime);
 
     if (config->debugTiming)

src/openalpr/colorfilter.cpp

@@ -29,7 +29,7 @@ namespace alpr
   ColorFilter::ColorFilter(Mat image, Mat characterMask, Config* config)
   {
     timespec startTime;
-    getTime(&startTime);
+    getTimeMonotonic(&startTime);
 
     this->config = config;
 
@@ -53,7 +53,7 @@ namespace alpr
     if (config->debugTiming)
     {
       timespec endTime;
-      getTime(&endTime);
+      getTimeMonotonic(&endTime);
       cout << "  -- ColorFilter Time: " << diffclock(startTime, endTime) << "ms." << endl;
     }
   }

src/openalpr/detection/detectorcpu.cpp

@@ -102,7 +102,7 @@ namespace alpr
 
     //-- Detect plates
     timespec startTime;
-    getTime(&startTime);
+    getTimeMonotonic(&startTime);
 
     float maxWidth = ((float) w) * (config->maxPlateWidthPercent / 100.0f) * this->scale_factor;
     float maxHeight = ((float) h) * (config->maxPlateHeightPercent / 100.0f) * this->scale_factor;
@@ -118,7 +118,7 @@ namespace alpr
     if (config->debugTiming)
     {
       timespec endTime;
-      getTime(&endTime);
+      getTimeMonotonic(&endTime);
       cout << "LBP Time: " << diffclock(startTime, endTime) << "ms." << endl;
     }
 

src/openalpr/detection/detectorcuda.cpp

@@ -98,7 +98,7 @@ namespace alpr
 
     //-- Detect plates
     timespec startTime;
-    getTime(&startTime);
+    getTimeMonotonic(&startTime);
 
     float maxWidth = ((float) w) * (config->maxPlateWidthPercent / 100.0f) * this->scale_factor;
     float maxHeight = ((float) h) * (config->maxPlateHeightPercent / 100.0f) * this->scale_factor;
@@ -121,7 +121,7 @@ namespace alpr
     if (config->debugTiming)
     {
       timespec endTime;
-      getTime(&endTime);
+      getTimeMonotonic(&endTime);
       cout << "LBP Time: " << diffclock(startTime, endTime) << "ms." << endl;
     }
 

src/openalpr/edges/platecorners.cpp

@@ -53,7 +53,7 @@ namespace alpr
       cout << "PlateCorners::findPlateCorners" << endl;
 
     timespec startTime;
-    getTime(&startTime);
+    getTimeMonotonic(&startTime);
 
     int horizontalLines = this->plateLines->horizontalLines.size();
     int verticalLines = this->plateLines->verticalLines.size();
@@ -118,7 +118,7 @@ namespace alpr
     if (pipelineData->config->debugTiming)
     {
       timespec endTime;
-      getTime(&endTime);
+      getTimeMonotonic(&endTime);
       cout << "Plate Corners Time: " << diffclock(startTime, endTime) << "ms." << endl;
     }
 

src/openalpr/edges/platelines.cpp

@@ -47,7 +47,7 @@ namespace alpr
       cout << "PlateLines findLines" << endl;
 
     timespec startTime;
-    getTime(&startTime);
+    getTimeMonotonic(&startTime);
 
 
     // Ignore input images that are pure white or pure black
@@ -129,7 +129,7 @@ namespace alpr
     if (pipelineData->config->debugTiming)
     {
       timespec endTime;
-      getTime(&endTime);
+      getTimeMonotonic(&endTime);
       cout << "Plate Lines Time: " << diffclock(startTime, endTime) << "ms." << endl;
     }
 

src/openalpr/licenseplatecandidate.cpp

@@ -69,7 +69,7 @@ namespace alpr
       {
 
         timespec startTime;
-        getTime(&startTime);
+        getTimeMonotonic(&startTime);
 
 
         Mat originalCrop = pipeline_data->crop_gray;
@@ -113,7 +113,7 @@ namespace alpr
         if (config->debugTiming)
         {
           timespec endTime;
-          getTime(&endTime);
+          getTimeMonotonic(&endTime);
           cout << "deskew Time: " << diffclock(startTime, endTime) << "ms." << endl;
         }
 

src/openalpr/ocr.cpp

@@ -54,7 +54,7 @@ namespace alpr
   void OCR::performOCR(PipelineData* pipeline_data)
   {
     timespec startTime;
-    getTime(&startTime);
+    getTimeMonotonic(&startTime);
 
     postProcessor.clear();
 
@@ -131,7 +131,7 @@ namespace alpr
     if (config->debugTiming)
     {
       timespec endTime;
-      getTime(&endTime);
+      getTimeMonotonic(&endTime);
       cout << "OCR Time: " << diffclock(startTime, endTime) << "ms." << endl;
     }
   }

src/openalpr/postprocess.cpp

@@ -152,7 +152,7 @@ namespace alpr
   void PostProcess::analyze(string templateregion, int topn)
   {
     timespec startTime;
-    getTime(&startTime);
+    getTimeMonotonic(&startTime);
 
     // Get a list of missing positions
     for (int i = letters.size() -1; i >= 0; i--)
@@ -201,7 +201,7 @@ namespace alpr
     findAllPermutations(tmp, 0, config->postProcessMaxSubstitutions);
 
     timespec sortStartTime;
-    getTime(&sortStartTime);
+    getTimeMonotonic(&sortStartTime);
 
     int numelements = topn;
     if (allPossibilities.size() < topn)
@@ -212,7 +212,7 @@ namespace alpr
     if (config->debugTiming)
     {
       timespec sortEndTime;
-      getTime(&sortEndTime);
+      getTimeMonotonic(&sortEndTime);
       cout << " -- PostProcess Sort Time: " << diffclock(sortStartTime, sortEndTime) << "ms." << endl;
     }
 
@@ -290,7 +290,7 @@ namespace alpr
     if (config->debugTiming)
     {
       timespec endTime;
-      getTime(&endTime);
+      getTimeMonotonic(&endTime);
       cout << "PostProcess Time: " << diffclock(startTime, endTime) << "ms." << endl;
     }
 

src/openalpr/segmentation/charactersegmenter.cpp

@@ -40,7 +40,7 @@ namespace alpr
     //CharacterRegion charRegion(img, debug);
 
     timespec startTime;
-    getTime(&startTime);
+    getTimeMonotonic(&startTime);
 
     if (pipeline_data->plate_inverted)
       bitwise_not(pipeline_data->crop_gray, pipeline_data->crop_gray);
@@ -110,7 +110,7 @@ namespace alpr
       // Do the histogram analysis to figure out char regions
 
       timespec startTime;
-      getTime(&startTime);
+      getTimeMonotonic(&startTime);
 
       vector<Mat> allHistograms;
 
@@ -166,7 +166,7 @@ namespace alpr
       if (config->debugTiming)
       {
         timespec endTime;
-        getTime(&endTime);
+        getTimeMonotonic(&endTime);
         cout << "  -- Character Segmentation Create and Score Histograms Time: " << diffclock(startTime, endTime) << "ms." << endl;
       }
 
@@ -189,7 +189,7 @@ namespace alpr
         }
       }
 
-      getTime(&startTime);
+      getTimeMonotonic(&startTime);
 
       filterEdgeBoxes(pipeline_data->thresholds, candidateBoxes, medianCharWidth, avgCharHeight);
       candidateBoxes = filterMostlyEmptyBoxes(pipeline_data->thresholds, candidateBoxes);
@@ -204,7 +204,7 @@ namespace alpr
       if (config->debugTiming)
       {
         timespec endTime;
-        getTime(&endTime);
+        getTimeMonotonic(&endTime);
         cout << "  -- Character Segmentation Box cleaning/filtering Time: " << diffclock(startTime, endTime) << "ms." << endl;
       }
 
@@ -226,7 +226,7 @@ namespace alpr
     if (config->debugTiming)
     {
       timespec endTime;
-      getTime(&endTime);
+      getTimeMonotonic(&endTime);
       cout << "Character Segmenter Time: " << diffclock(startTime, endTime) << "ms." << endl;
     }
   }

src/openalpr/stateidentifier.cpp

@@ -52,7 +52,7 @@ namespace alpr
   bool StateIdentifier::recognize(PipelineData* pipeline_data)
   {
     timespec startTime;
-    getTime(&startTime);
+    getTimeMonotonic(&startTime);
 
     Mat plateImg = Mat(pipeline_data->grayImg, pipeline_data->regionOfInterest);
 
@@ -75,7 +75,7 @@ namespace alpr
     if (config->debugTiming)
     {
       timespec endTime;
-      getTime(&endTime);
+      getTimeMonotonic(&endTime);
       cout << "State Identification Time: " << diffclock(startTime, endTime) << "ms." << endl;
     }
 

src/openalpr/support/timing.cpp

@@ -71,11 +71,24 @@ namespace alpr
     return (0);
   }
 
-  void getTime(timespec* time)
+  void getTimeMonotonic(timespec* time)
   {
     clock_gettime(0, time);
   }
   
+  long getTimeMonotonicMs()
+  {
+    timespec time;
+    getTimeMonotonic(&time);
+
+    timespec time_start;
+    time_start.tv_sec = 0;
+    time_start.tv_nsec = 0;
+
+    return diffclock(time_start, time);
+  }
+  
+  
   double diffclock(timespec time1,timespec time2)
   {
     timespec delta = diff(time1,time2);
@@ -101,26 +114,48 @@ namespace alpr
   }
 
 
-  long getEpochTime()
+  long getEpochTimeMs()
   {
     return std::time(0) * 1000;
   } 
 
   #else
 
-  void getTime(timespec* time)
+  void _getTime(bool realtime, timespec* time)
   {
-  #ifdef __MACH__ // OS X does not have clock_gettime, use clock_get_time
+    #ifdef __MACH__ // OS X does not have clock_gettime, use clock_get_time
-    clock_serv_t cclock;
+      clock_serv_t cclock;
-    mach_timespec_t mts;
+      mach_timespec_t mts;
-    host_get_clock_service(mach_host_self(), CALENDAR_CLOCK, &cclock);
+      host_get_clock_service(mach_host_self(), CALENDAR_CLOCK, &cclock);
-    clock_get_time(cclock, &mts);
+      clock_get_time(cclock, &mts);
-    mach_port_deallocate(mach_task_self(), cclock);
+      mach_port_deallocate(mach_task_self(), cclock);
-    time->tv_sec = mts.tv_sec;
+      time->tv_sec = mts.tv_sec;
-    time->tv_nsec = mts.tv_nsec;
+      time->tv_nsec = mts.tv_nsec;
-  #else
+    #else
-    clock_gettime(CLOCK_MONOTONIC, time);
+      if (realtime)
-  #endif
+        clock_gettime(CLOCK_REALTIME, time);
+      else
+        clock_gettime(CLOCK_MONOTONIC, time);
+    #endif
+  }
+  
+  // Returns a monotonic clock time unaffected by time changes (e.g., NTP)
+  // Useful for interval comparisons
+  void getTimeMonotonic(timespec* time)
+  {
+    _getTime(false, time);
+  }
+  
+  long getTimeMonotonicMs()
+  {
+    timespec time;
+    getTimeMonotonic(&time);
+
+    timespec time_start;
+    time_start.tv_sec = 0;
+    time_start.tv_nsec = 0;
+
+    return diffclock(time_start, time);
   }
 
   double diffclock(timespec time1,timespec time2)
@@ -148,13 +183,18 @@ namespace alpr
   }
 
 
-  long getEpochTime()
+  // Returns wall clock time since Unix epoch (Jan 1, 1970)
+  long getEpochTimeMs()
   {
-      struct timeval tp;
+    timespec time;
-      gettimeofday(&tp, NULL);
+    _getTime(true, &time);
-      long ms = tp.tv_sec * 1000 + tp.tv_usec / 1000;
+
+    timespec epoch_start;
+    epoch_start.tv_sec = 0;
+    epoch_start.tv_nsec = 0;
+
+    return diffclock(epoch_start, time);
 
-      return ms;
   } 
 
   #endif

src/openalpr/support/timing.h

@@ -26,10 +26,12 @@
 namespace alpr
 {
 
-  void getTime(timespec* time);
+  void getTimeMonotonic(timespec* time);
+  long getTimeMonotonicMs();
+  
   double diffclock(timespec time1,timespec time2);
 
-  long getEpochTime();
+  long getEpochTimeMs();
 
 }
 

src/openalpr/textdetection/characteranalysis.cpp

@@ -56,7 +56,7 @@ namespace alpr
 
 
     timespec startTime;
-    getTime(&startTime);
+    getTimeMonotonic(&startTime);
 
     pipeline_data->textLines.clear();
 
@@ -70,12 +70,12 @@ namespace alpr
     if (config->debugTiming)
     {
       timespec endTime;
-      getTime(&endTime);
+      getTimeMonotonic(&endTime);
       cout << "  -- Character Analysis Find Contours Time: " << diffclock(startTime, endTime) << "ms." << endl;
     }
     //Mat img_equalized = equalizeBrightness(img_gray);
 
-    getTime(&startTime);
+    getTimeMonotonic(&startTime);
 
     for (unsigned int i = 0; i < pipeline_data->thresholds.size(); i++)
     {
@@ -88,7 +88,7 @@ namespace alpr
     if (config->debugTiming)
     {
       timespec endTime;
-      getTime(&endTime);
+      getTimeMonotonic(&endTime);
       cout << "  -- Character Analysis Filter Time: " << diffclock(startTime, endTime) << "ms." << endl;
     }
 
@@ -206,7 +206,7 @@ namespace alpr
     if (config->debugTiming)
     {
       timespec endTime;
-      getTime(&endTime);
+      getTimeMonotonic(&endTime);
       cout << "Character Analysis Time: " << diffclock(startTime, endTime) << "ms." << endl;
     }
 

src/openalpr/utility.cpp

@@ -121,7 +121,7 @@ namespace alpr
     //Mat img_equalized = equalizeBrightness(img_gray);
 
     timespec startTime;
-    getTime(&startTime);
+    getTimeMonotonic(&startTime);
 
     vector<Mat> thresholds;
 
@@ -160,7 +160,7 @@ namespace alpr
     if (config->debugTiming)
     {
       timespec endTime;
-      getTime(&endTime);
+      getTimeMonotonic(&endTime);
       cout << "  -- Produce Threshold Time: " << diffclock(startTime, endTime) << "ms." << endl;
     }
 

src/tests/test_api.cpp

@@ -20,7 +20,7 @@ using namespace alpr;
 TEST_CASE( "JSON Serialization/Deserialization", "[json]" ) {
   
   AlprResults origResults;
-  origResults.epoch_time = getEpochTime();
+  origResults.epoch_time = getEpochTimeMs();
   origResults.img_width = 640;
   origResults.img_height = 480;
   origResults.total_processing_time_ms = 100;