ubuntu pdf 乱码 ，我的解决方案

1，安装 poppler-data

2，修改 /etc/fonts/conf.d/49-sansserif.conf

3，自己配置字体替换，在 ~/.fonts.conf 中

见 http://freedesktop.org/wiki/Software/poppler

<alias bind="same">
    <family>Font A</family>
    <accept><family>Font B</family></accept>
</alias>


If that does not work for you use 

<match target="pattern">
 <test name="family">
  <string>Font A</string>
 </test>
 <edit name="family" mode="prepend" binding="same">
  <string>Font B</string>
 </edit>
</match>