diff --git a/src/function.js b/src/function.js
index 56b405ede..2088ee219 100644
--- a/src/function.js
+++ b/src/function.js
@@ -103,11 +103,12 @@ var PDFFunction = (function PDFFunctionClosure() {
 
       var size = dict.get('Size');
       var bps = dict.get('BitsPerSample');
-      var order = dict.get('Order');
-      if (!order)
-        order = 1;
-      if (order !== 1)
-        error('No support for cubic spline interpolation: ' + order);
+      var order = dict.get('Order') || 1;
+      if (order !== 1) {
+        // No description how cubic spline interpolation works in PDF32000:2008
+        // As in poppler, ignoring order, linear interpolation may work as good
+        TODO('No support for cubic spline interpolation: ' + order);
+      }
 
       var encode = dict.get('Encode');
       if (!encode) {