Subtitles: Try to reenable the previously selected caption type.

During DVD playback with AVSubs enabled, once in a while the decoder
disables and reenables subtitles.  If the DVD also contains cc608
captions, the caption priority order would favor cc608 and the user
would need to reselect AVSubs every time this happens.  To fix this,
we keep track of the previously selected caption type and default to
that if possible when captions are turned on.  This is in addition to
the existing code that tries to reselect the previous AVSubs track
when AVSubs are enabled.

mythtv/libs/libmythbase/mythversion.h

@@ -12,7 +12,7 @@
 /// Update this whenever the plug-in API changes.
 /// Including changes in the libmythbase, libmyth, libmythtv, libmythav* and
 /// libmythui class methods used by plug-ins.
-#define MYTH_BINARY_VERSION "0.25.20120314-3"
+#define MYTH_BINARY_VERSION "0.25.20120315-1"
 
 /** \brief Increment this whenever the MythTV network protocol changes.
  *

mythtv/libs/libmythtv/mythplayer.cpp

@@ -165,6 +165,7 @@ MythPlayer::MythPlayer(PlayerFlags flags)
       // General Caption/Teletext/Subtitle support
       textDisplayMode(kDisplayNone),
       prevTextDisplayMode(kDisplayNone),
+      prevNonzeroTextDisplayMode(kDisplayNone),
       // Support for analog captions and teletext
       vbimode(VBIMode::None),
       ttPageNum(0x888),
@@ -1317,6 +1318,8 @@ void MythPlayer::ResetCaptions(void)
 
 void MythPlayer::DisableCaptions(uint mode, bool osd_msg)
 {
+    if (textDisplayMode)
+        prevNonzeroTextDisplayMode = textDisplayMode;
     textDisplayMode &= ~mode;
     ResetCaptions();
 
@@ -1394,6 +1397,8 @@ void MythPlayer::EnableCaptions(uint mode, bool osd_msg)
         .arg(mode).arg(msg));
 
     textDisplayMode = mode;
+    if (textDisplayMode)
+        prevNonzeroTextDisplayMode = textDisplayMode;
     if (osd_msg)
         SetOSDMessage(msg, kOSDTimeout_Med);
 }
@@ -1432,7 +1437,8 @@ void MythPlayer::SetCaptionsEnabled(bool enable, bool osd_msg)
         DisableCaptions(origMode, osd_msg);
         return;
     }
-    int mode = NextCaptionTrack(kDisplayNone);
+    int mode = HasCaptionTrack(prevNonzeroTextDisplayMode) ?
+        prevNonzeroTextDisplayMode : NextCaptionTrack(kDisplayNone);
     if (origMode != (uint)mode)
     {
         DisableCaptions(origMode, false);
@@ -1642,6 +1648,23 @@ void MythPlayer::ChangeCaptionTrack(int dir)
     }
 }
 
+bool MythPlayer::HasCaptionTrack(int mode)
+{
+    if (mode == kDisplayNone)
+        return false;
+    if (((mode == kDisplayTextSubtitle) && HasTextSubtitles()) ||
+         (mode == kDisplayNUVTeletextCaptions))
+    {
+        return true;
+    }
+    else if (!(mode == kDisplayTextSubtitle) &&
+               decoder->GetTrackCount(toTrackType(mode)))
+    {
+        return true;
+    }
+    return false;
+}
+
 int MythPlayer::NextCaptionTrack(int mode)
 {
     // Text->TextStream->708/608->608/708->AVSubs->Teletext->NUV->None
@@ -1666,17 +1689,9 @@ int MythPlayer::NextCaptionTrack(int mode)
     else if (kDisplayNone == mode)
         nextmode = kDisplayTextSubtitle;
 
-    if (((nextmode == kDisplayTextSubtitle) && HasTextSubtitles()) ||
-         (nextmode == kDisplayNUVTeletextCaptions) ||
-         (nextmode == kDisplayNone))
-    {
-        return nextmode;
-    }
-    else if (!(nextmode == kDisplayTextSubtitle) &&
-               decoder->GetTrackCount(toTrackType(nextmode)))
-    {
+    if (nextmode == kDisplayNone || HasCaptionTrack(nextmode))
         return nextmode;
-    }
+
     return NextCaptionTrack(nextmode);
 }
 

mythtv/libs/libmythtv/mythplayer.h

@@ -478,6 +478,7 @@ class MTV_PUBLIC MythPlayer
     int  GetTrack(uint type);
     int  ChangeTrack(uint type, int dir);
     void ChangeCaptionTrack(int dir);
+    bool HasCaptionTrack(int mode);
     int  NextCaptionTrack(int mode);
     void DoDisableForcedSubtitles(void);
     void DoEnableForcedSubtitles(void);
@@ -674,6 +675,7 @@ class MTV_PUBLIC MythPlayer
     // General Caption/Teletext/Subtitle support
     uint     textDisplayMode;
     uint     prevTextDisplayMode;
+    uint     prevNonzeroTextDisplayMode;
 
     // Support for analog captions and teletext
     // (i.e. Vertical Blanking Interval (VBI) encoded data.)