HEADER support. Taken from w3c#6

Author: emmanent

parser.js

@@ -64,17 +64,33 @@
         err("No valid signature. (File needs to start with \"WEBVTT\".)")
       }
 
-      linePos++
-
-      /* HEADER */
-      while(lines[linePos] != "" && lines[linePos] != undefined) {
-        err("No blank line after the signature.")
-        if(lines[linePos].indexOf("-->") != -1) {
-          alreadyCollected = true
+    /* HEADER */
+    while(lines[linePos] !== undefined) {
+      line = lines[linePos]
+      /* look-ahead */
+      if (line === "") {
+        if ((lines[linePos+1] && lines[linePos+1].indexOf("-->") !== -1 )||
+        (lines[linePos+2] && lines[linePos+2].indexOf("-->") !== -1)) {
           break
+        } else {
+          linePos++
+          continue
+        }
+      } else {
+        if ((line.match(/:/g) || []).length !== 1) {
+          err("Metadata header line needs to consist of a name and value separated by a ':' character.")
+          if (line.indexOf("-->") != -1) {
+            err("Cues need to be separated from the Header by a blank line.")
+            alreadyCollected = true
+          }
+        }
+        if (line.substring(0,6) !== "Region") {
+          err("Metadata headers other than Region are not defined.")
+          alreadyCollected = true
         }
         linePos++
       }
+    }
 
       /* CUE LOOP */
       while(lines[linePos] != undefined) {