Fetch decodeParams if it's a |Ref| in JBIG2Decode streams

src/core/stream.js

@@ -1033,7 +1033,8 @@ var Jbig2Stream = (function Jbig2StreamClosure() {
 
     var jbig2Image = new Jbig2Image();
 
-    var chunks = [], decodeParams = this.dict.get('DecodeParms');
+    var chunks = [], xref = this.dict.xref;
+    var decodeParams = xref.fetchIfRef(this.dict.get('DecodeParms'));
 
     // According to the PDF specification, DecodeParms can be either
     // a dictionary, or an array whose elements are dictionaries.
@@ -1042,7 +1043,7 @@ var Jbig2Stream = (function Jbig2StreamClosure() {
         warn('JBIG2 - \'DecodeParms\' array with multiple elements ' +
              'not supported.');
       }
-      decodeParams = decodeParams[0];
+      decodeParams = xref.fetchIfRef(decodeParams[0]);
     }
     if (decodeParams && decodeParams.has('JBIG2Globals')) {
       var globalsStream = decodeParams.get('JBIG2Globals');