source: multimedia/libdriv/liba52.xml@ 181e069f

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
   "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
  <!ENTITY % general-entities SYSTEM "../../general.ent">
  %general-entities;

  <!ENTITY liba52-download-http
  "https://liba52.sourceforge.net/files/a52dec-&liba52-version;.tar.gz">
  <!ENTITY liba52-download-ftp  " ">
  <!ENTITY liba52-md5sum        "caa9f5bc44232dc8aeea773fea56be80">
  <!ENTITY liba52-size          "236 KB">
  <!ENTITY liba52-buildsize     "2.5 MB">
  <!ENTITY liba52-time          "less than 0.1 SBU">
]>

<sect1 id="liba52" xreflabel="liba52-&liba52-version;">
  <?dbhtml filename="liba52.html"?>


  <title>Liba52-&liba52-version;</title>

  <indexterm zone="liba52">
    <primary sortas="a-Liba52">Liba52</primary>
  </indexterm>

  <sect2 role="package">
    <title>Introduction to Liba52</title>

    <para>
      <application>liba52</application> is a free library for decoding
      ATSC A/52 (also known as AC-3) streams. The A/52 standard is used
      in a variety of applications, including digital television and DVD.
    </para>

    &lfs121_checked;

    <bridgehead renderas="sect3">Package Information</bridgehead>
    <itemizedlist spacing="compact">
      <listitem>
        <para>
          Download (HTTP): <ulink url="&liba52-download-http;"/>
        </para>
      </listitem>
      <listitem>
        <para>
          Download (FTP): <ulink url="&liba52-download-ftp;"/>
        </para>
      </listitem>
      <listitem>
        <para>
          Download MD5 sum: &liba52-md5sum;
        </para>
      </listitem>
      <listitem>
        <para>
          Download size: &liba52-size;
        </para>
      </listitem>
      <listitem>
        <para>
          Estimated disk space required: &liba52-buildsize;
        </para>
      </listitem>
      <listitem>
        <para>
          Estimated build time: &liba52-time;
        </para>
      </listitem>
    </itemizedlist>

    <bridgehead renderas="sect4">Optional</bridgehead>
    <para role="optional">
      <ulink url="https://cr.yp.to/djbfft.html">djbfft</ulink>
    </para>

    <para condition="html" role="usernotes">
      Editor Notes: <ulink url="&blfs-wiki;/liba52"/>
    </para>

  </sect2>

  <sect2 role="installation">
    <title>Installation of Liba52</title>

    <para>
      Install <application>liba52</application> by running the
      following commands:
    </para>

<screen><userinput>./configure --prefix=/usr           \
            --mandir=/usr/share/man \
            --enable-shared         \
            --disable-static        \
            CFLAGS="${CFLAGS:--g -O3} -fPIC" &amp;&amp;
make</userinput></screen>

    <para>
      To test the results, issue: <command>make check</command>.
    </para>

    <para>
      Now, as the <systemitem class="username">root</systemitem>
      user:
    </para>

<screen role="root"><userinput>make install &amp;&amp;
cp liba52/a52_internal.h /usr/include/a52dec &amp;&amp;
install -v -m644 -D doc/liba52.txt \
    /usr/share/doc/liba52-&liba52-version;/liba52.txt</userinput></screen>
  </sect2>

  <sect2 role="commands">
    <title>Command Explanations</title>

    <para>
      <parameter>CFLAGS="${CFLAGS:--g -O3} -fPIC"</parameter>: This appends
      <option>-fPIC</option> to <envar>CFLAGS</envar> but use
      <option>-g -O3</option> (the default of this package) instead of an
      empty string when <envar>CFLAGS</envar> is not set.
      This is needed to compile <application>liba52</application> without
      runtime text relocation.  Runtime text relocation is prohibited on
      x86_64 so <option>-fPIC</option> is strictly required.  On 32-bit x86
      runtime text relocation is allowed but it's insecure and it may waste
      physical RAM, so <option>-fPIC</option> is still better.
    </para>

    <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
      href="../../xincludes/static-libraries.xml"/>

    <para>
      <command>cp liba52/a52_internal.h ...</command>: Copying this header
      file into /usr/include/a52dec allows some other programs (such as
      <application>xine-lib</application>) to compile and link against a system
      installed <application>liba52</application>.
    </para>
  </sect2>

  <sect2 role="content">
    <title>Contents</title>

    <segmentedlist>
      <segtitle>Installed Programs</segtitle>
      <segtitle>Installed Library</segtitle>
      <segtitle>Installed Directories</segtitle>

      <seglistitem>
        <seg>a52dec and extract_a52</seg>
        <seg>liba52.so</seg>
        <seg>/usr/include/a52dec and
        /usr/share/doc/liba52-&liba52-version;</seg>
      </seglistitem>
    </segmentedlist>

    <variablelist>
      <bridgehead renderas="sect3">Short Descriptions</bridgehead>
      <?dbfo list-presentation="list"?>
      <?dbhtml list-presentation="table"?>

      <varlistentry id="a52dec">
        <term><command>a52dec</command></term>
        <listitem>
          <para>
            plays ATSC A/52 audio streams
          </para>
          <indexterm zone="liba52 a52dec">
            <primary sortas="b-a52dec">a52dec</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="extract_a52">
        <term><command>extract_a52</command></term>
        <listitem>
          <para>
            extracts ATSC A/52 audio from an MPEG stream
          </para>
          <indexterm zone="liba52 extract_a52">
            <primary sortas="b-extract_a52">extract_a52</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="liba52-lib">
        <term><filename class="libraryfile">liba52.so</filename></term>
        <listitem>
          <para>
            provides functions for the programs dealing with ATSC A/52 streams
          </para>
          <indexterm zone="liba52 liba52-lib">
            <primary sortas="c-liba52">liba52.so</primary>
          </indexterm>
        </listitem>
      </varlistentry>
    </variablelist>
  </sect2>

</sect1>