move Matroska specific things to the MatroskaExtractor

library/src/main/java/com/google/android/exoplayer2/extractor/mkv/MatroskaExtractor.java

@@ -1498,7 +1498,10 @@ public final class MatroskaExtractor implements Extractor {
           break;
         case CODEC_ID_ASS:
           mimeType = MimeTypes.TEXT_SSA;
-          initializationData = Collections.singletonList(codecPrivate);
+          initializationData = new ArrayList<>(3);
+          // this dialogue format is specific to Matroska
+          initializationData.add("Start, End, ReadOrder, Layer, Style, Name, MarginL, MarginR, MarginV, Effect, Text".getBytes());
+          initializationData.add(codecPrivate);
           break;
         case CODEC_ID_VOBSUB:
           mimeType = MimeTypes.APPLICATION_VOBSUB;

library/src/main/java/com/google/android/exoplayer2/text/SubtitleDecoderFactory.java

@@ -25,6 +25,9 @@ import com.google.android.exoplayer2.text.webvtt.Mp4WebvttDecoder;
 import com.google.android.exoplayer2.text.webvtt.WebvttDecoder;
 import com.google.android.exoplayer2.util.MimeTypes;
 
+import java.util.List;
+
+import static android.R.attr.initialKeyguardLayout;
 import static android.R.attr.mimeType;
 
 /**
@@ -79,8 +82,10 @@ public interface SubtitleDecoderFactory {
           throw new IllegalArgumentException("Attempted to create decoder for unsupported format");
         }
         if(clazz == SSADecoder.class) {
-          return clazz.asSubclass(SubtitleDecoder.class).getConstructor(byte[].class)
-                  .newInstance(format.initializationData.get(0));
+          byte[] header = format.initializationData.get(1);
+          byte[] dialogueFormat = format.initializationData.get(0);
+          return clazz.asSubclass(SubtitleDecoder.class).getConstructor(byte[].class, byte[].class)
+                  .newInstance(header, dialogueFormat);
         }
         if (clazz == Cea608Decoder.class) {
           return clazz.asSubclass(SubtitleDecoder.class).getConstructor(String.class, Integer.TYPE)

library/src/main/java/com/google/android/exoplayer2/text/ssa/SSADecoder.java

@@ -8,12 +8,14 @@ import com.google.android.exoplayer2.util.ParsableByteArray;
 
 import java.io.UnsupportedEncodingException;
 import java.util.HashMap;
+import java.util.List;
 import java.util.Locale;
 import java.util.Map;
 
 import static android.R.attr.data;
 import static android.R.attr.subtitle;
 import static android.R.attr.x;
+import static android.media.CamcorderProfile.get;
 
 /**
  * Created by cablej01 on 26/12/2016.
@@ -65,26 +67,23 @@ import static android.R.attr.x;
  */
 public class SSADecoder extends SimpleSubtitleDecoder {
     private static final String TAG = "SSADecoder";
-    private static String defaultDialogueFormat = "Start, End, ReadOrder, Layer, Style, Name, MarginL, MarginR, MarginV, Effect, Text";
-    private static String defaultStyleFormat = "Name, Fontname, Fontsize, PrimaryColour, SecondaryColour, OutlineColour, BackColour, Bold, Italic, Underline, StrikeOut, ScaleX, ScaleY, Spacing, Angle, BorderStyle, Outline, Shadow, Alignment, MarginL, MarginR, MarginV, Encoding";
-    private String[] dialogueFormat;
-    private String[] styleFormat;
+    private String[] dialogueFormat = null;
+    private String[] styleFormat = null;
     private Map<String,Style> styles = new HashMap<>();
 
-// 0,0,Watamote-internal/narrator,Serinuma,0000,0000,0000,      ,The prince should be with the princess.
-//  , ,style                     ,name    ,L   ,R,   V   ,Effect, text
     public SSADecoder() {
         super("SSADecoder");
-        dialogueFormat = parseKeys(defaultDialogueFormat);
-        styleFormat = parseKeys(defaultStyleFormat);
     }
 
-    public SSADecoder(byte[] header) {
+    public SSADecoder(byte[] header, byte[] dialogueFormatBytes) {
         super("SSADecoder");
-        styleFormat = parseKeys(defaultStyleFormat);
         decodeHeader(header, header.length);
-        // put back the Matroska format
-        dialogueFormat = parseKeys(defaultDialogueFormat);
+        try {
+            dialogueFormat = parseKeys(new String(dialogueFormatBytes, "UTF-8"));
+        }
+        catch (UnsupportedEncodingException e) {
+            // can't happen?
+        }
     }
 
     /**