diff --git a/.buildinfo b/.buildinfo
index 634671e..e99cab2 100644
--- a/.buildinfo
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@@ -1,4 +1,4 @@
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diff --git a/_static/documentation_options.js b/_static/documentation_options.js
index 45ad0c1..167445d 100644
--- a/_static/documentation_options.js
+++ b/_static/documentation_options.js
@@ -1,6 +1,6 @@
 var DOCUMENTATION_OPTIONS = {
     URL_ROOT: document.getElementById("documentation_options").getAttribute('data-url_root'),
-    VERSION: '1.17',
+    VERSION: '1.18',
     LANGUAGE: 'en',
     COLLAPSE_INDEX: false,
     BUILDER: 'html',
diff --git a/genindex.html b/genindex.html
index ac3e627..c3549dc 100644
--- a/genindex.html
+++ b/genindex.html
@@ -3,7 +3,7 @@
 <head>
   <meta charset="utf-8" />
   <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-  <title>Index &mdash; kaldifeat 1.17 documentation</title>
+  <title>Index &mdash; kaldifeat 1.18 documentation</title>
       <link rel="stylesheet" href="_static/pygments.css" type="text/css" />
       <link rel="stylesheet" href="_static/css/theme.css" type="text/css" />
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@@ -28,7 +28,7 @@
             <a href="index.html" class="icon icon-home"> kaldifeat
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               <div class="version">
-                1.17
+                1.18
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diff --git a/index.html b/index.html
index c363b6a..9cddf1e 100644
--- a/index.html
+++ b/index.html
@@ -4,7 +4,7 @@
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   <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-  <title>kaldifeat &mdash; kaldifeat 1.17 documentation</title>
+  <title>kaldifeat &mdash; kaldifeat 1.18 documentation</title>
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       <link rel="stylesheet" href="_static/css/theme.css" type="text/css" />
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diff --git a/installation.html b/installation.html
index f9a40bc..9174219 100644
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@@ -4,7 +4,7 @@
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   <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-  <title>Installation &mdash; kaldifeat 1.17 documentation</title>
+  <title>Installation &mdash; kaldifeat 1.18 documentation</title>
       <link rel="stylesheet" href="_static/pygments.css" type="text/css" />
       <link rel="stylesheet" href="_static/css/theme.css" type="text/css" />
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@@ -31,7 +31,7 @@
             <a href="index.html" class="icon icon-home"> kaldifeat
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+                1.18
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diff --git a/intro.html b/intro.html
index 222ece3..7c617c1 100644
--- a/intro.html
+++ b/intro.html
@@ -4,7 +4,7 @@
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   <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-  <title>Introduction &mdash; kaldifeat 1.17 documentation</title>
+  <title>Introduction &mdash; kaldifeat 1.18 documentation</title>
       <link rel="stylesheet" href="_static/pygments.css" type="text/css" />
       <link rel="stylesheet" href="_static/css/theme.css" type="text/css" />
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@@ -31,7 +31,7 @@
             <a href="index.html" class="icon icon-home"> kaldifeat
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-                1.17
+                1.18
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 <div role="search">
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diff --git a/objects.inv b/objects.inv
index 0627869..9c7fcaf 100644
--- a/objects.inv
+++ b/objects.inv
@@ -1,5 +1,5 @@
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index e33c9a5..f73b4f3 100644
--- a/search.html
+++ b/search.html
@@ -3,7 +3,7 @@
 <head>
   <meta charset="utf-8" />
   <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-  <title>Search &mdash; kaldifeat 1.17 documentation</title>
+  <title>Search &mdash; kaldifeat 1.18 documentation</title>
       <link rel="stylesheet" href="_static/pygments.css" type="text/css" />
       <link rel="stylesheet" href="_static/css/theme.css" type="text/css" />
     
@@ -31,7 +31,7 @@
             <a href="index.html" class="icon icon-home"> kaldifeat
           </a>
               <div class="version">
-                1.17
+                1.18
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   <form id="rtd-search-form" class="wy-form" action="#" method="get">
diff --git a/usage/fbank.html b/usage/fbank.html
index 7e14e51..8c60d98 100644
--- a/usage/fbank.html
+++ b/usage/fbank.html
@@ -4,7 +4,7 @@
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   <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-  <title>kaldifeat.Fbank &mdash; kaldifeat 1.17 documentation</title>
+  <title>kaldifeat.Fbank &mdash; kaldifeat 1.18 documentation</title>
       <link rel="stylesheet" href="../_static/pygments.css" type="text/css" />
       <link rel="stylesheet" href="../_static/css/theme.css" type="text/css" />
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@@ -31,7 +31,7 @@
             <a href="../index.html" class="icon icon-home"> kaldifeat
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-                1.17
+                1.18
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 <div role="search">
   <form id="rtd-search-form" class="wy-form" action="../search.html" method="get">
diff --git a/usage/fbank_options.html b/usage/fbank_options.html
index e3649fb..a732099 100644
--- a/usage/fbank_options.html
+++ b/usage/fbank_options.html
@@ -4,7 +4,7 @@
   <meta charset="utf-8" /><meta name="generator" content="Docutils 0.17.1: http://docutils.sourceforge.net/" />
 
   <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-  <title>kaldifeat.FbankOptions &mdash; kaldifeat 1.17 documentation</title>
+  <title>kaldifeat.FbankOptions &mdash; kaldifeat 1.18 documentation</title>
       <link rel="stylesheet" href="../_static/pygments.css" type="text/css" />
       <link rel="stylesheet" href="../_static/css/theme.css" type="text/css" />
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@@ -31,7 +31,7 @@
             <a href="../index.html" class="icon icon-home"> kaldifeat
           </a>
               <div class="version">
-                1.17
+                1.18
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   <form id="rtd-search-form" class="wy-form" action="../search.html" method="get">
diff --git a/usage/index.html b/usage/index.html
index 36eb13b..d3815a8 100644
--- a/usage/index.html
+++ b/usage/index.html
@@ -4,7 +4,7 @@
   <meta charset="utf-8" /><meta name="generator" content="Docutils 0.17.1: http://docutils.sourceforge.net/" />
 
   <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-  <title>Usage &mdash; kaldifeat 1.17 documentation</title>
+  <title>Usage &mdash; kaldifeat 1.18 documentation</title>
       <link rel="stylesheet" href="../_static/pygments.css" type="text/css" />
       <link rel="stylesheet" href="../_static/css/theme.css" type="text/css" />
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@@ -31,7 +31,7 @@
             <a href="../index.html" class="icon icon-home"> kaldifeat
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+                1.18
               </div>
 <div role="search">
   <form id="rtd-search-form" class="wy-form" action="../search.html" method="get">
diff --git a/usage/online_fbank.html b/usage/online_fbank.html
index 7a1766b..784d888 100644
--- a/usage/online_fbank.html
+++ b/usage/online_fbank.html
@@ -4,7 +4,7 @@
   <meta charset="utf-8" /><meta name="generator" content="Docutils 0.17.1: http://docutils.sourceforge.net/" />
 
   <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-  <title>kaldifeat.OnlineFbank &mdash; kaldifeat 1.17 documentation</title>
+  <title>kaldifeat.OnlineFbank &mdash; kaldifeat 1.18 documentation</title>
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       <link rel="stylesheet" href="../_static/css/theme.css" type="text/css" />
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