diff --git a/TODO b/TODO
index 27c056a..6c5aa73 100644
--- a/TODO
+++ b/TODO
@@ -1,4 +1,4 @@
-better solution for ascent/descent (cross-platform, embeded/not)
+check exact asc/dsc
 
 option to embed local matched fonts for non-embedded ones
 
diff --git a/share/all.css b/share/all.css
index 9d5b559..e3f9f89 100644
--- a/share/all.css
+++ b/share/all.css
@@ -19,7 +19,7 @@
 .l {
   position:absolute;
   white-space:pre;
-  font-size:0;
+  font-size:1px;
   transform-origin:0% 190%;
   -ms-transform-origin:0% 100%;
   -moz-transform-origin:0% 100%;
diff --git a/src/HTMLRenderer.h b/src/HTMLRenderer.h
index e159d48..f789df2 100644
--- a/src/HTMLRenderer.h
+++ b/src/HTMLRenderer.h
@@ -130,7 +130,7 @@ class HTMLRenderer : public OutputDev
         // manage styles
         ////////////////////////////////////////////////////
         FontInfo install_font(GfxFont * font);
-        void install_embedded_font(GfxFont * font, const std::string & suffix, long long fn_id, bool & use_tounicode);
+        void install_embedded_font(GfxFont * font, const std::string & suffix, long long fn_id, FontInfo & info);
         void install_base_font(GfxFont * font, GfxFontLoc * font_loc, long long fn_id);
         void install_external_font (GfxFont * font, long long fn_id);
 
@@ -149,7 +149,7 @@ class HTMLRenderer : public OutputDev
          * remote font: to be retrieved from the web server
          * local font: to be substituted with a local (client side) font
          */
-        void export_remote_font(long long fn_id, const std::string & suffix, const std::string & fontfileformat, GfxFont * font);
+        void export_remote_font(const FontInfo & info, const std::string & suffix, const std::string & fontfileformat, GfxFont * font);
         void export_remote_default_font(long long fn_id);
         void export_local_font(long long fn_id, GfxFont * font, const std::string & original_font_name, const std::string & cssfont);
 
diff --git a/src/HTMLRenderer/export.cc b/src/HTMLRenderer/export.cc
index 59a81ea..1e14d70 100644
--- a/src/HTMLRenderer/export.cc
+++ b/src/HTMLRenderer/export.cc
@@ -16,21 +16,22 @@
 
 using boost::algorithm::ifind_first;
 
-void HTMLRenderer::export_remote_font(long long fn_id, const string & suffix, const string & fontfileformat, GfxFont * font)
+void HTMLRenderer::export_remote_font(const FontInfo & info, const string & suffix, const string & fontfileformat, GfxFont * font)
 {
-    allcss_fout << format("@font-face{font-family:f%|1$x|;src:url(") % fn_id;
+    allcss_fout << format("@font-face{font-family:f%|1$x|;src:url(") % info.id;
 
-    const std::string fn = (format("f%|1$x|%2%") % fn_id % suffix).str();
+    const std::string fn = (format("f%|1$x|") % info.id).str();
     if(param->single_html)
     {
-        allcss_fout << "'data:font/" << fontfileformat << ";base64," << base64stream(ifstream(tmp_dir / fn, ifstream::binary)) << "'";
+        allcss_fout << "'data:font/" << fontfileformat << ";base64," << base64stream(ifstream(tmp_dir / (fn+suffix), ifstream::binary)) << "'";
     }
     else
     {
-        allcss_fout << fn;
+        allcss_fout << (fn+suffix);
     }
+    
 
-    allcss_fout << format(")format(\"%1%\");}.f%|2$x|{font-family:f%|2$x|;line-height:%3%;}") % fontfileformat % fn_id % (font->getAscent() - font->getDescent()) << endl;
+    allcss_fout << format(")format(\"%1%\");}.f%|2$x|{font-family:f%|2$x|;line-height:%3%;}") % fontfileformat % info.id % (info.ascent - info.descent) << endl;
 }
 
 static string general_font_family(GfxFont * font)
diff --git a/src/HTMLRenderer/install.cc b/src/HTMLRenderer/install.cc
index 9835ceb..a983065 100644
--- a/src/HTMLRenderer/install.cc
+++ b/src/HTMLRenderer/install.cc
@@ -19,7 +19,6 @@
 #include "namespace.h"
 
 using std::all_of;
-using std::round;
 
 FontInfo HTMLRenderer::install_font(GfxFont * font)
 {
@@ -68,7 +67,7 @@ FontInfo HTMLRenderer::install_font(GfxFont * font)
                     string suffix = dump_embedded_font(font, new_fn_id);
                     if(suffix != "")
                     {
-                        install_embedded_font(font, suffix, new_fn_id, cur_info_iter->second.use_tounicode);
+                        install_embedded_font(font, suffix, new_fn_id, cur_info_iter->second);
                     }
                     else
                     {
@@ -99,7 +98,7 @@ FontInfo HTMLRenderer::install_font(GfxFont * font)
 
 // TODO
 // add a new function and move to text.cc
-void HTMLRenderer::install_embedded_font(GfxFont * font, const string & suffix, long long fn_id, bool & use_tounicode)
+void HTMLRenderer::install_embedded_font(GfxFont * font, const string & suffix, long long fn_id, FontInfo & info)
 {
     string fn = (format("f%|1$x|") % fn_id).str();
 
@@ -202,7 +201,7 @@ void HTMLRenderer::install_embedded_font(GfxFont * font, const string & suffix,
      * 
      */
 
-    use_tounicode = ((suffix == ".ttf") || (font->isCIDFont()) || (param->always_apply_tounicode));
+    info.use_tounicode = ((suffix == ".ttf") || (font->isCIDFont()) || (param->always_apply_tounicode));
 
     auto ctu = font->getToUnicode();
 
@@ -220,7 +219,7 @@ void HTMLRenderer::install_embedded_font(GfxFont * font, const string & suffix,
 
         Unicode u, *pu=&u;
 
-        if(use_tounicode)
+        if(info.use_tounicode)
         {
             int n = 0;
             if(ctu)
@@ -247,16 +246,45 @@ void HTMLRenderer::install_embedded_font(GfxFont * font, const string & suffix,
     if(ctu)
         ctu->decRefCnt();
 
-    script_fout << format("Generate(%1%)") % ((param->single_html ? tmp_dir : dest_dir) / (fn+".ttf")) << endl;
+    auto dest = ((param->single_html ? tmp_dir : dest_dir) / (fn+".ttf"));
     if(param->single_html)
         add_tmp_file(fn+".ttf");
 
-    if(system((boost::format("fontforge -script %1% 2>%2%") % script_path % (tmp_dir / NULL_FILENAME)).str().c_str()) != 0)
+    script_fout << format("Generate(%1%)") % dest << endl;
+    script_fout << format("Open(%1%, 1)") % dest << endl;
+
+    for(const string & s1 : {"Win", "Typo", "HHead"})
+    {
+        for(const string & s2 : {"Ascent", "Descent"})
+        {
+            script_fout << "Print(GetOS2Value(\"" << s1 << s2 << "\"))" << endl;
+        }
+    }
+    script_fout << "SetOS2Value(\"TypoLineGap\", 0)" << endl;
+    script_fout << "SetOS2Value(\"HHeadLineGap\", 0)" << endl;
+    script_fout << format("Generate(%1%)") % dest << endl;
+
+    if(system((boost::format("fontforge -script %1% 1>%2% 2>%3%") % script_path % (tmp_dir / (fn+".info")) % (tmp_dir / NULL_FILENAME)).str().c_str()) != 0)
         cerr << "Warning: fontforge failed." << endl;
 
+    add_tmp_file(fn+".info");
     add_tmp_file(NULL_FILENAME);
 
-    export_remote_font(fn_id, ".ttf", "truetype", font);
+    // read metric
+    int WinAsc, WinDes, TypoAsc, TypoDes, HHeadAsc, HHeadDes;
+    if(ifstream(tmp_dir / (fn+".info")) >> WinAsc >> WinDes >> TypoAsc >> TypoDes >> HHeadAsc >> HHeadDes)
+    {
+        double em = TypoAsc - TypoDes;
+        info.ascent = ((double)HHeadAsc) / em;
+        info.descent = ((double)HHeadDes) / em;
+    }
+    else
+    {
+        info.ascent = font->getAscent();
+        info.descent = font->getDescent();
+    }
+
+    export_remote_font(info, ".ttf", "truetype", font);
 }
 
 void HTMLRenderer::install_base_font(GfxFont * font, GfxFontLoc * font_loc, long long fn_id)
diff --git a/src/HTMLRenderer/state.cc b/src/HTMLRenderer/state.cc
index 1c24a43..5581c9b 100644
--- a/src/HTMLRenderer/state.cc
+++ b/src/HTMLRenderer/state.cc
@@ -354,11 +354,11 @@ void HTMLRenderer::prepare_line(GfxState * state)
 
             // TODO class for height
             html_fout << format("<div style=\"left:%1%px;bottom:%2%px;height:%4%px;line-height:%5%px;\" class=\"l t%|3$x|\">")
-                % x 
+                % x
                 % y
                 % cur_tm_id
-                % (state->getFont()->getAscent() * draw_font_size)
-                % (2*(state->getFont()->getAscent() * draw_font_size))
+                % (cur_font_info.ascent * draw_font_size)
+                % (2 * cur_font_info.ascent * draw_font_size)
                 ;
 
             //resync position
diff --git a/src/util.h b/src/util.h
index 84dbe63..853bc23 100644
--- a/src/util.h
+++ b/src/util.h
@@ -14,6 +14,7 @@
 #include <istream>
 #include <ostream>
 #include <iostream>
+#include <cmath>
 
 #include <GfxState.h>
 #include <GfxFont.h>
@@ -29,6 +30,7 @@ using std::noskipws;
 using std::endl;
 using std::flush;
 using std::cerr;
+using std::floor;
 
 // mute gcc warning of unused function
 namespace
@@ -178,6 +180,7 @@ class FontInfo
 public:
     long long id;
     bool use_tounicode;
+    double ascent, descent;
 };
 
 // wrapper of the transform matrix double[6]