Fix PAL autodetection:

* Be more tolerant when waiting for vsync during TV mode autodetect.
  * Count PAL and NTSC frames during autodetect, use the mode with
    more statistics.

src/emucore/Console.cxx

@@ -54,6 +54,7 @@
 #include "Serializable.hxx"
 #include "Version.hxx"
 #include "TvMode.hxx"
+#include "FrameManager.hxx"
 
 #ifdef DEBUGGER_SUPPORT
   #include "Debugger.hxx"
@@ -116,11 +117,20 @@ Console::Console(OSystem& osystem, unique_ptr<Cartridge>& cart,
     // The 'fastscbios' option must be changed before the system is reset
     bool fastscbios = myOSystem.settings().getBool("fastscbios");
     myOSystem.settings().setValue("fastscbios", true);
+
+    uInt8 initialGarbageFrames = FrameManager::initialGarbageFrames();
+    uInt8 linesPAL = 0;
+    uInt8 linesNTSC = 0;
+
     mySystem->reset(true);  // autodetect in reset enabled
     myTIA->autodetectTvMode(true);
-    for(int i = 0; i < 80; ++i)
+    for(int i = 0; i < 60; ++i) {
+      if (i > initialGarbageFrames) myTIA->tvMode() == TvMode::pal ? linesPAL++ : linesNTSC++;
+
       myTIA->update();
-    myDisplayFormat = myTIA->tvMode() == TvMode::pal ? "PAL" : "NTSC";
+    }
+
+    myDisplayFormat = linesPAL > linesNTSC  ? "PAL" : "NTSC";
     if(myProperties.get(Display_Format) == "AUTO")
     {
       autodetected = "*";

src/emucore/tia/FrameManager.cxx

@@ -29,11 +29,12 @@ enum Metrics: uInt32 {
   overscanNTSC                  = 30,
   overscanPAL                   = 36,
   vsync                         = 3,
-  vsyncLimit                    = 30,
+  maxLinesVsync                 = 30,
+  maxLinesVsyncDuringAutodetect = 100,
   visibleOverscan               = 20,
   maxUnderscan                  = 10,
   tvModeDetectionTolerance      = 20,
-  initialGarbageFrames          = 20,
+  initialGarbageFrames          = 10,
   framesForModeConfirmation     = 5,
   maxVblankViolations           = 2,
   minStableVblankFrames         = 1
@@ -43,6 +44,16 @@ static constexpr uInt32
   frameLinesNTSC = Metrics::vsync + Metrics::vblankNTSC + Metrics::kernelNTSC + Metrics::overscanNTSC,
   frameLinesPAL = Metrics::vsync + Metrics::vblankPAL + Metrics::kernelPAL + Metrics::overscanPAL;
 
+inline static uInt32 vsyncLimit(bool autodetect) {
+  return autodetect ? maxLinesVsyncDuringAutodetect : maxLinesVsync;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+uInt8 FrameManager::initialGarbageFrames()
+{
+  return Metrics::initialGarbageFrames;
+}
+
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 FrameManager::FrameManager()
   : myMode(TvMode::pal),
@@ -95,15 +106,15 @@ void FrameManager::nextLine()
   switch (myState)
   {
     case State::waitForVsyncStart:
-      if (Int32(myLineInState) > Int32(myFrameLines - myCurrentFrameFinalLines) || !myCurrentFrameFinalLines)
+      if (Int32(myLineInState) >= Int32(myFrameLines - myCurrentFrameFinalLines) || !myCurrentFrameFinalLines)
         myVsyncLines++;
 
-      if (myVsyncLines > Metrics::vsyncLimit) setState(State::waitForFrameStart);
+      if (myVsyncLines > vsyncLimit(myAutodetectTvMode)) setState(State::waitForFrameStart);
 
       break;
 
     case State::waitForVsyncEnd:
-      if (++myVsyncLines > Metrics::vsyncLimit)
+      if (++myVsyncLines > vsyncLimit(myAutodetectTvMode))
         setState(State::waitForFrameStart);
 
       break;
@@ -131,7 +142,7 @@ void FrameManager::nextLineInVsync()
     case VblankMode::floating:
 
       if (shouldTransition) {
-        if (myTotalFrames > initialGarbageFrames && myLineInState == myLastVblankLines)
+        if (myTotalFrames > Metrics::initialGarbageFrames && myLineInState == myLastVblankLines)
           myStableVblankFrames++;
         else
           myStableVblankFrames = 0;

src/emucore/tia/FrameManager.hxx

@@ -35,6 +35,9 @@ class FrameManager : public Serializable
     FrameManager();
 
   public:
+
+    static uInt8 initialGarbageFrames();
+
     void setHandlers(callback frameStartCallback, callback frameCompletionCallback);
 
     void reset();