Ticket #10793: scene-change-detector.diff

mythtv/programs/mythcommflag/ClassicCommDetector.cpp

@@ -152 +152 @@
     preRoll(0),                                postRoll(0)
 {
     commDetectBorder =
-        gCoreContext->GetNumSetting("CommDetectBorder", 20);
+        gCoreContext->GetNumSetting("CommDetectBorder", 5);
     commDetectBlankFrameMaxDiff =
         gCoreContext->GetNumSetting("CommDetectBlankFrameMaxDiff", 25);
     commDetectDarkBrightness =
@@ -206 +206 @@
             .arg(width).arg(height)
             .arg(player->GetFrameRate()).arg(commDetectMethod));
 
-    if ((width * height) > 1000000)
+    /*if ((width * height) > 1000000)
     {
         horizSpacing = 10;
         vertSpacing = 10;
@@ -230 +230 @@
     {
         horizSpacing = 4;
         vertSpacing = 4;
-    }
+    }*/
 
+    horizSpacing = 1;
+    vertSpacing = 1;
+    
     LOG(VB_COMMFLAG, LOG_INFO,
         QString("Using Sample Spacing of %1 horizontal & %2 vertical pixels.")
             .arg(horizSpacing).arg(vertSpacing));
@@ -790 +793 @@
         {
             fInfo.aspect = frameInfo[lastFrameNumber].aspect;
             fInfo.format = frameInfo[lastFrameNumber].format;
+            fInfo.flagMask = COMM_FRAME_SKIPPED;
+            while (++lastFrameNumber < curFrameNumber)
+            {
+                // Only overwrite if there was no info for the frame yet
+                if (!frameInfo.contains(lastFrameNumber))
+                    frameInfo[lastFrameNumber] = fInfo;
+            }
         }
-        fInfo.flagMask = COMM_FRAME_SKIPPED;
-
-        lastFrameNumber++;
-        while(lastFrameNumber < curFrameNumber)
-            frameInfo[lastFrameNumber++] = fInfo;
-
         fInfo.flagMask = 0;
     }
     lastFrameNumber = curFrameNumber;
@@ -808 +812 @@
 
     if (commDetectMethod & COMM_DETECT_SCENE)
     {
-        sceneChangeDetector->processFrame(framePtr);
+        sceneChangeDetector->processFrame(curFrameNumber, framePtr);
     }
 
     stationLogoPresent = false;
@@ -1397 +1401 @@
                 fbp->score += 20;
             }
 
-            if ((fbp->scRate > 1.0) &&
-                (fbp->logoCount < (fbp->frames * .90)))
+            if ((fbp->scRate > 0.75) &&
+                (fbp->logoCount < (fbp->frames * .25)))
             {
                 if (verboseDebugging)
-                    LOG(VB_COMMFLAG, LOG_DEBUG, "      scRate > 1.0, -10");
+                    LOG(VB_COMMFLAG, LOG_DEBUG, "      scRate > 0.75, -10");
                 fbp->score -= 10;
 
-                if (fbp->scRate > 2.0)
+                if (fbp->scRate > 1.5)
                 {
                     if (verboseDebugging)
-                        LOG(VB_COMMFLAG, LOG_DEBUG, "      scRate > 2.0, -10");
+                        LOG(VB_COMMFLAG, LOG_DEBUG, "      scRate > 1.5, -10");
                     fbp->score -= 10;
                 }
             }

mythtv/programs/mythcommflag/ClassicSceneChangeDetector.cpp

@@ -8 +8 @@
         unsigned int height, unsigned int commdetectborder_in,
         unsigned int xspacing_in, unsigned int yspacing_in):
     SceneChangeDetectorBase(width,height),
-    frameNumber(0),
     previousFrameWasSceneChange(false),
     xspacing(xspacing_in),
     yspacing(yspacing_in),
@@ -25 +24 @@
     SceneChangeDetectorBase::deleteLater();
 }
 
-void ClassicSceneChangeDetector::processFrame(unsigned char* frame)
+void ClassicSceneChangeDetector::processFrame(unsigned int frameNumber, unsigned char* frame)
 {
     histogram->generateFromImage(frame, width, height, commdetectborder,
                                  width-commdetectborder, commdetectborder,
@@ -38 +37 @@
     previousFrameWasSceneChange = isSceneChange;
 
     std::swap(histogram,previousHistogram);
-    frameNumber++;
 }
 
 /* vim: set expandtab tabstop=4 shiftwidth=4: */

mythtv/programs/mythcommflag/ClassicSceneChangeDetector.h

@@ -13 +13 @@
         unsigned int yspacing);
     virtual void deleteLater(void);
 
-    void processFrame(unsigned char* frame);
+    void processFrame(unsigned int frameNumber, unsigned char* frame);
 
   private:
     ~ClassicSceneChangeDetector() {}
@@ -21 +21 @@
   private:
     Histogram* histogram;
     Histogram* previousHistogram;
-    unsigned int frameNumber;
     bool previousFrameWasSceneChange;
     unsigned int xspacing, yspacing;
     unsigned int commdetectborder;

mythtv/programs/mythcommflag/Histogram.cpp

@@ -70 +70 @@
 
 float Histogram::calculateSimilarityWith(const Histogram& other) const
 {
-    long similar = 0;
-
-    for(unsigned int i = 0; i < 256; i++)
+    const int proximity = 5;
+    long similarity = 0;
+
+    similarity += std::min(data[0],
+                           other.data[0]);
+    similarity += std::min(data[0] + data[1],
+                           other.data[0] + other.data[1]);
+    similarity += std::min(data[0] + data[1] + data[2],
+                           other.data[0] + other.data[1] + other.data[2]);
+    
+    for(unsigned int i = 0; i <= 256 - proximity; i++)
     {
-        if (data[i] < other.data[i])
-            similar += data[i];
-        else
-            similar += other.data[i];
+        unsigned int mine = 0, others = 0;
+        for (int j = 0; j < proximity; ++j)
+        {
+            mine += data[i+j];
+            others += other.data[i+j];
+        }
+        similarity += std::min(mine, others);
     }
-
-    //Using c style cast for old gcc compatibility.
-    return static_cast<float>(similar) / static_cast<float>(numberOfSamples);
+    
+    similarity += std::min(data[253] + data[254] + data[255],
+                           other.data[253] + other.data[254] + other.data[255]);
+    similarity += std::min(data[254] + data[255],
+                           other.data[254] + other.data[255]);
+    similarity += std::min(data[255],
+                           other.data[255]);
+    
+    return similarity / static_cast<float>(numberOfSamples * proximity);
 }
 
 /* vim: set expandtab tabstop=4 shiftwidth=4: */

mythtv/programs/mythcommflag/SceneChangeDetectorBase.h

@@ -11 +11 @@
     SceneChangeDetectorBase(unsigned int w, unsigned int h) :
         width(w), height(h) {}
 
-    virtual void processFrame(unsigned char *frame) = 0;
+    virtual void processFrame(unsigned int frameNumber, unsigned char *frame) = 0;
 
   signals:
     void haveNewInformation(unsigned int framenum, bool scenechange,