Caption language query improvements.

 Adds GetCaptionLanguage() which allows you to query the caption language by type and ID.
 Uses GetCaptionLanguage() to guess at the language of an unspecified CC1 or CC3 stream by using the service 1 and service 2 languages (In practice the CC1 and CC3 are in the same lanuage as service 1 and service 2, especially when they are not described in the caption descriptor.)

mythtv/libs/libmythtv/avformatdecoder.cpp

@@ -2212,6 +2212,7 @@ void AvFormatDecoder::DoFastForwardSeek(long long desiredFrame, bool &needflush)
     return;
 }
 
+/// Returns DVD Subtitle language
 int AvFormatDecoder::GetSubtitleLanguage(uint subtitle_index, uint stream_index)
 {
     (void)subtitle_index;
@@ -2222,6 +2223,35 @@ int AvFormatDecoder::GetSubtitleLanguage(uint subtitle_index, uint stream_index)
                      iso639_str3_to_key("und");
 }
 
+/// Return ATSC Closed Caption Language
+int AvFormatDecoder::GetCaptionLanguage(TrackTypes trackType, int service_num)
+{
+    int ret = -1;
+    for (uint i = 0; i < (uint) pmt_track_types.size(); i++)
+    {
+        if ((pmt_track_types[i] == trackType) &&
+            (pmt_tracks[i].stream_id == service_num))
+        {
+            ret = pmt_tracks[i].language;
+            if (!iso639_is_key_undefined(ret))
+                return ret;
+        }
+    }
+
+    for (uint i = 0; i < (uint) stream_track_types.size(); i++)
+    {
+        if ((stream_track_types[i] == trackType) &&
+            (stream_tracks[i].stream_id == service_num))
+        {
+            ret = stream_tracks[i].language;
+            if (!iso639_is_key_undefined(ret))
+                return ret;
+        }
+    }
+
+    return ret;
+}
+
 int AvFormatDecoder::GetAudioLanguage(uint audio_index, uint stream_index)
 {
     return GetSubtitleLanguage(audio_index, stream_index);
@@ -2614,24 +2644,31 @@ void AvFormatDecoder::UpdateCaptionTracksFromStreams(
     stream_track_types.clear();
     int av_index = selectedTrack[kTrackTypeVideo].av_stream_index;
     int lang = iso639_str3_to_key("und");
-    for (uint i = 0; i < 4; i++)
+    for (uint i = 1; i < 64; i++)
     {
-        if (seen_608[i])
+        if (seen_708[i] && !ccX08_in_pmt[i+4])
         {
             StreamInfo si(av_index, lang, 0/*lang_idx*/,
-                          i+1, false/*easy*/, false/*wide*/);
+                          i, false/*easy*/, true/*wide*/);
             stream_tracks.push_back(si);
-            stream_track_types.push_back(kTrackTypeCC608);
+            stream_track_types.push_back(kTrackTypeCC708);
         }
     }
-    for (uint i = 1; i < 64; i++)
+    for (uint i = 0; i < 4; i++)
     {
-        if (seen_708[i] && !ccX08_in_pmt[i+4])
+        if (seen_608[i] && !ccX08_in_pmt[i])
         {
+            if (0==i)
+                lang = GetCaptionLanguage(kTrackTypeCC708, 1);
+            else if (2==i)
+                lang = GetCaptionLanguage(kTrackTypeCC708, 2);
+            else
+                lang = iso639_str3_to_key("und");
+
             StreamInfo si(av_index, lang, 0/*lang_idx*/,
-                          i, false/*easy*/, true/*wide*/);
+                          i+1, false/*easy*/, false/*wide*/);
             stream_tracks.push_back(si);
-            stream_track_types.push_back(kTrackTypeCC708);
+            stream_track_types.push_back(kTrackTypeCC608);
         }
     }
     UpdateATSCCaptionTracks();

mythtv/libs/libmythtv/avformatdecoder.h

@@ -176,6 +176,11 @@ class AvFormatDecoder : public DecoderBase
     virtual bool SetAudioByComponentTag(int tag);
     virtual bool SetVideoByComponentTag(int tag);
 
+    // Stream language info
+    virtual int GetSubtitleLanguage(uint subtitle_index, uint stream_index);
+    virtual int GetCaptionLanguage(TrackTypes trackType, int service_num);
+    virtual int GetAudioLanguage(uint audio_index, uint stream_index);
+
   protected:
     RingBuffer *getRingBuf(void) { return ringBuffer; }
 
@@ -250,8 +255,6 @@ class AvFormatDecoder : public DecoderBase
     virtual void DoFastForwardSeek(long long desiredFrame, bool &needflush);
     virtual void StreamChangeCheck(void) { }
     virtual void PostProcessTracks(void) { }
-    virtual int GetSubtitleLanguage(uint subtitle_index, uint stream_index);
-    virtual int GetAudioLanguage(uint audio_index, uint stream_index);
 
     PrivateDecoder *private_dec;