path: root/en_US.ISO8859-1/books/handbook/multimedia/chapter.xml

<?xml version="1.0" encoding="iso-8859-1"?>
<!--
     The FreeBSD Documentation Project

     $FreeBSD$
-->
<chapter xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink" version="5.0" xml:id="multimedia">
  <!--
  <chapterinfo>
    <authorgroup>
      <author>
	<firstname>Ross</firstname>
	<surname>Lippert</surname>
	<contrib>Edited by </contrib>
      </author>
    </authorgroup>
  </chapterinfo>
  -->

  <title>Multimedia</title>

  <sect1 xml:id="multimedia-synopsis">
    <title>Synopsis</title>

    <para>&os; supports a wide variety of sound cards, allowing users
      to enjoy high fidelity output from a &os; system.  This includes
      the ability to record and playback audio in the MPEG Audio Layer
      3 (<acronym>MP3</acronym>), Waveform Audio File
      (<acronym>WAV</acronym>), Ogg Vorbis, and other formats.  The
      &os; Ports Collection contains many applications for editing
      recorded audio, adding sound effects, and controlling attached
      MIDI devices.</para>

    <para>&os; also supports the playback of video files and
      <acronym>DVD</acronym>s.  The &os; Ports Collection contains
      applications to encode, convert, and playback various video
      media.</para>

    <para>This chapter describes how to configure sound cards, video
      playback, TV tuner cards, and scanners on &os;.  It also
      describes some of the applications which are available for
      using these devices.</para>

    <para>After reading this chapter, you will know how to:</para>

    <itemizedlist>
      <listitem>
	<para>Configure a sound card on &os;.</para>
      </listitem>

      <listitem>
	<para>Troubleshoot the sound setup.</para>
      </listitem>

      <listitem>
	<para>Playback and encode MP3s and other audio.</para>
      </listitem>

      <listitem>
	<para>Prepare a &os; system for video playback.</para>
      </listitem>

      <listitem>
	<para>Play <acronym>DVD</acronym>s, <filename>.mpg</filename>,
	  and <filename>.avi</filename> files.</para>
      </listitem>

      <listitem>
	<para>Rip CD and <acronym>DVD</acronym> content into
	  files.</para>
      </listitem>

      <listitem>
	<para>Configure a TV card.</para>
      </listitem>

      <listitem>
	<para>Install and setup MythTV on &os;</para>
      </listitem>

      <listitem>
	<para>Configure an image scanner.</para>
      </listitem>
    </itemizedlist>

    <para>Before reading this chapter, you should:</para>

    <itemizedlist>
      <listitem><para>Know how to install applications as described in
	<xref linkend="ports"/>.</para></listitem>
    </itemizedlist>
  </sect1>

  <sect1 xml:id="sound-setup">
    <!--
    <sect1info>
      <authorgroup>
	<author>
	  <firstname>Moses</firstname>
	  <surname>Moore</surname>
	  <contrib>Contributed by in November 2000</contrib>
	</author>
      </authorgroup>
      <authorgroup>
	<author>
	  <firstname>Marc</firstname>
	  <surname>Fonvieille</surname>
	  <contrib>Enhanced by in September 2004</contrib>
	</author>
      </authorgroup>
    </sect1info>
    -->

    <title>Setting Up the Sound Card</title>

    <indexterm><primary>PCI</primary></indexterm>
    <indexterm><primary>sound cards</primary></indexterm>
    <para>Before beginning the configuration, determine the model of
      the sound card and the chip it uses.  &os; supports a wide
      variety of sound cards.  Check the supported audio devices
      list of the <link xlink:href="&rel.current.hardware;">Hardware
	Notes</link> to see if the card is supported and which &os;
      driver it uses.</para>

    <indexterm>
      <primary>kernel</primary>
      <secondary>configuration</secondary>
    </indexterm>

    <para>In order to use the sound device, its device driver must be
      loaded.  The easiest way is to load a kernel module for the
      sound card with &man.kldload.8;.  This example loads the driver
      for a built-in audio chipset based on the Intel
      specification:</para>

    <screen>&prompt.root; <userinput>kldload snd_hda</userinput></screen>

    <para>To automate the loading of this driver at boot time, add the
      driver to <filename>/boot/loader.conf</filename>. The line for
      this driver is:</para>

    <programlisting>snd_hda_load="YES"</programlisting>

    <para>Other available sound modules are listed in
      <filename>/boot/defaults/loader.conf</filename>.  When unsure
      which driver to use, load the <filename>snd_driver</filename>
      module:</para>

    <screen>&prompt.root; <userinput>kldload snd_driver</userinput></screen>

    <para>This is a metadriver which loads all of the most common
      sound drivers and can be used to speed up the search for the
      correct driver.  It is also possible to load all sound drivers
      by adding the metadriver to
      <filename>/boot/loader.conf</filename>.</para>

    <para>To determine which driver was selected for the sound card
      after loading the <filename>snd_driver</filename> metadriver,
      type <command>cat /dev/sndstat</command>.</para>

    <sect2>
      <title>Configuring a Custom Kernel with Sound Support</title>

      <para>This section is for users who prefer to statically compile
	in support for the sound card in a custom kernel.  For more
	information about recompiling a kernel, refer to <xref linkend="kernelconfig"/>.</para>

      <para>When using a custom kernel to provide sound support, make
	sure that the audio framework driver exists in the custom
	kernel configuration file:</para>

      <programlisting>device sound</programlisting>

      <para>Next, add support for the sound card.  To continue the
	example of the built-in audio chipset based on the Intel
	specification from the previous section, use the following
	line in the custom kernel configuration file:</para>

      <programlisting>device snd_hda</programlisting>

      <para>Be sure to read the manual page of the driver for the
	device name to use for the driver.</para>

      <para>Non-PnP ISA sound cards may require the IRQ and I/O port
	settings of the card to be added to
	<filename>/boot/device.hints</filename>.  During the boot
	process, &man.loader.8; reads this file and passes the
	settings to the kernel.  For example, an old Creative
	&soundblaster; 16 ISA non-PnP card will use the
	&man.snd.sbc.4; driver in conjunction with
	<literal>snd_sb16</literal>.  For this card, the following
	lines must be added to the kernel configuration file:</para>

      <programlisting>device snd_sbc
device snd_sb16</programlisting>

      <para>If the card uses the <literal>0x220</literal> I/O port and
	IRQ <literal>5</literal>, these lines must also be added to
	<filename>/boot/device.hints</filename>:</para>

      <programlisting>hint.sbc.0.at="isa"
hint.sbc.0.port="0x220"
hint.sbc.0.irq="5"
hint.sbc.0.drq="1"
hint.sbc.0.flags="0x15"</programlisting>

      <para>In this case, the card uses the <literal>0x220</literal>
	I/O port and the IRQ <literal>5</literal>.</para>

      <para>The syntax used in
	<filename>/boot/device.hints</filename> is described in
	&man.sound.4; and the manual page for the driver of the sound
	card.</para>

      <para>The settings shown above are the defaults.  In some
	cases, the IRQ or other settings may need to be changed to
	match the card.  Refer to &man.snd.sbc.4; for more information
	about this card.</para>
    </sect2>

    <sect2 xml:id="sound-testing">
      <title>Testing Sound</title>

      <para>After loading the required module or rebooting into the
	custom kernel, the sound card should be detected.  To confirm,
	run <command>dmesg | grep pcm</command>.  This example is
	from a system with a built-in Conexant CX20590 chipset:</para>

      <screen>pcm0: &lt;NVIDIA (0x001c) (HDMI/DP 8ch)&gt; at nid 5 on hdaa0
pcm1: &lt;NVIDIA (0x001c) (HDMI/DP 8ch)&gt; at nid 6 on hdaa0
pcm2: &lt;Conexant CX20590 (Analog 2.0+HP/2.0)&gt; at nid 31,25 and 35,27 on hdaa1</screen>

      <para>The status of the sound card may also be checked using
	this command:</para>

      <screen>&prompt.root; <userinput>cat /dev/sndstat</userinput>
FreeBSD Audio Driver (newpcm: 64bit 2009061500/amd64)
Installed devices:
pcm0: &lt;NVIDIA (0x001c) (HDMI/DP 8ch)&gt; (play)
pcm1: &lt;NVIDIA (0x001c) (HDMI/DP 8ch)&gt; (play)
pcm2: &lt;Conexant CX20590 (Analog 2.0+HP/2.0)&gt; (play/rec) default</screen>

      <para>The output will vary depending upon the sound card.  If no
	<filename>pcm</filename> devices are listed, double-check
	that the correct device driver was loaded or compiled into the
	kernel.  The next section lists some common problems and their
	solutions.</para>

      <para>If all goes well, the sound card should now work in os;.
	If the <acronym>CD</acronym> or <acronym>DVD</acronym> drive
	is properly connected to the sound card, one can insert an
	audio CD in the drive and play it with
	&man.cdcontrol.1;:</para>

      <screen>&prompt.user; <userinput>cdcontrol -f /dev/acd0 play 1</userinput></screen>

      <warning>
	<para>Audio CDs have specialized encodings which means that
	  they should not be mounted using &man.mount.8;.</para>
      </warning>

      <para>Various applications, such as <package>audio/workman</package>, provide a
	friendlier interface.  The <package>audio/mpg123</package> port can be installed
	to listen to MP3 audio files.</para>

      <para>Another quick way to test the card is to send data to
	<filename>/dev/dsp</filename>:</para>

      <screen>&prompt.user; <userinput>cat filename &gt; /dev/dsp</userinput></screen>

      <para>where
	<filename>filename</filename> can
	be any type of file.  This command should produce some noise,
	confirming that the sound card is working.</para>

      <note>
	<para>The <filename>/dev/dsp*</filename> device nodes will
	  be created automatically as needed.  When not in use, they
	  do not exist and will not appear in the output of
	  &man.ls.1;.</para>
      </note>
    </sect2>

    <sect2 xml:id="troubleshooting">
      <title>Troubleshooting Sound</title>

      <indexterm><primary>device nodes</primary></indexterm>
      <indexterm><primary>I/O port</primary></indexterm>
      <indexterm><primary>IRQ</primary></indexterm>
      <indexterm><primary>DSP</primary></indexterm>

      <para>Table 8.1 lists some common error messages and their
	solutions:</para>

      <table frame="none" pgwide="1">
	<title>Common Error Messages</title>

	<tgroup cols="2">
	  <thead>
	    <row>
	      <entry>Error</entry>
	      <entry>Solution</entry>
	    </row>
	  </thead>

	  <tbody>
	    <row>
	      <entry><errorname>sb_dspwr(XX) timed
		  out</errorname></entry>
	      <entry><para>The I/O port is not set
		correctly.</para></entry>
	    </row>

	    <row>
	      <entry><errorname>bad irq XX</errorname></entry>
	      <entry><para>The IRQ is set incorrectly.  Make sure
		that the set IRQ and the sound IRQ are the
		same.</para></entry>
	    </row>

	    <row>
	      <entry><errorname>xxx: gus pcm not attached, out of
		  memory</errorname></entry>
	      <entry><para>There is not enough available memory to
		use the device.</para></entry>
	    </row>

	    <row>
	      <entry><errorname>xxx: can't open
		  /dev/dsp!</errorname></entry>
	      <entry><para>Type <command>fstat | grep
		  dsp</command> to check if another application is
		holding the device open.  Noteworthy troublemakers are
		<application>esound</application> and
		<application>KDE</application>'s sound
		support.</para></entry>
	    </row>
	  </tbody>
	</tgroup>
      </table>

      <para>Modern graphics cards often come with their own sound
	driver for use with <acronym>HDMI</acronym>.  This sound
	device is sometimes enumerated before the sound card meaning
	that the sound card will not be used as the default playback
	device.  To check if this is the case, run
	<application>dmesg</application> and look for
	<literal>pcm</literal>.  The output looks something like
	this:</para>

      <programlisting>...
hdac0: HDA Driver Revision: 20100226_0142
hdac1: HDA Driver Revision: 20100226_0142
hdac0: HDA Codec #0: NVidia (Unknown)
hdac0: HDA Codec #1: NVidia (Unknown)
hdac0: HDA Codec #2: NVidia (Unknown)
hdac0: HDA Codec #3: NVidia (Unknown)
pcm0: &lt;HDA NVidia (Unknown) PCM #0 DisplayPort&gt; at cad 0 nid 1 on hdac0
pcm1: &lt;HDA NVidia (Unknown) PCM #0 DisplayPort&gt; at cad 1 nid 1 on hdac0
pcm2: &lt;HDA NVidia (Unknown) PCM #0 DisplayPort&gt; at cad 2 nid 1 on hdac0
pcm3: &lt;HDA NVidia (Unknown) PCM #0 DisplayPort&gt; at cad 3 nid 1 on hdac0
hdac1: HDA Codec #2: Realtek ALC889
pcm4: &lt;HDA Realtek ALC889 PCM #0 Analog&gt; at cad 2 nid 1 on hdac1
pcm5: &lt;HDA Realtek ALC889 PCM #1 Analog&gt; at cad 2 nid 1 on hdac1
pcm6: &lt;HDA Realtek ALC889 PCM #2 Digital&gt; at cad 2 nid 1 on hdac1
pcm7: &lt;HDA Realtek ALC889 PCM #3 Digital&gt; at cad 2 nid 1 on hdac1
...</programlisting>

      <para>In this example, the graphics card
	(<literal>NVidia</literal>) has been enumerated before the
	sound card (<literal>Realtek ALC889</literal>).  To use the
	sound card as the default playback device, change
	<varname>hw.snd.default_unit</varname> to the unit that should
	be used for playback:</para>

      <screen>&prompt.root; <userinput>sysctl hw.snd.default_unit=n</userinput></screen>

      <para>where <literal>n</literal> is the number of the sound
	device to use.  In this example, it should be
	<literal>4</literal>.  Make this change permanent by adding
	the following line to
	<filename>/etc/sysctl.conf</filename>:</para>

      <programlisting>hw.snd.default_unit=<replaceable>4</replaceable></programlisting>
  </sect2>

  <sect2 xml:id="sound-multiple-sources">
    <!--
    <sect2info>
      <authorgroup>
	<author>
	  <firstname>Munish</firstname>
	  <surname>Chopra</surname>
	  <contrib>Contributed by </contrib>
	</author>
      </authorgroup>
    </sect2info>
    -->
    <title>Utilizing Multiple Sound Sources</title>

    <para>It is often desirable to have multiple sources of sound that
      are able to play simultaneously.  &os; uses <quote>Virtual
	Sound Channels</quote> to multiplex the
      sound card's playback by mixing sound in the kernel.</para>

    <para>Three &man.sysctl.8; knobs are available for configuring
      virtual channels:</para>

    <screen>&prompt.root; <userinput>sysctl dev.pcm.0.play.vchans=4</userinput>
&prompt.root; <userinput>sysctl dev.pcm.0.rec.vchans=4</userinput>
&prompt.root; <userinput>sysctl hw.snd.maxautovchans=4</userinput></screen>

    <para>This example allocates four virtual channels, which is a
      practical number for everyday use.  Both
      <varname>dev.pcm.0.play.vchans=4</varname> and
      <varname>dev.pcm.0.rec.vchans=4</varname> are configurable after
      a device has been attached and represent the number of virtual
      channels <filename>pcm0</filename> has for playback and
      recording.  Since the <filename>pcm</filename> module can be
      loaded independently of the hardware drivers,
      <varname>hw.snd.maxautovchans</varname> indicates how many
      virtual channels will be given to an audio device when it is
      attached.  Refer to &man.pcm.4; for more information.</para>

    <note>
      <para>The number of virtual channels for a device cannot be
	changed while it is in use.  First, close any programs using
	the device, such as music players or sound daemons.</para>
    </note>

    <para>
      The correct <filename>pcm</filename> device will
      automatically be allocated transparently to a program that
      requests <filename>/dev/dsp0</filename>.</para>
  </sect2>

  <sect2>
        <!--
    <sect2info>
      <authorgroup>
	<author>
	  <firstname>Josef</firstname>
	  <surname>El-Rayes</surname>
	  <contrib>Contributed by </contrib>
	</author>
      </authorgroup>
    </sect2info>
    -->

    <title>Setting Default Values for Mixer Channels</title>

    <para>The default values for the different mixer channels are
      hardcoded in the source code of the &man.pcm.4; driver.  While
      sound card mixer levels can be changed using &man.mixer.8; or
      third-party applications and daemons, this is not a permanent
      solution.  To instead set default mixer values at the driver
      level, define the appropriate values in
      <filename>/boot/device.hints</filename>, as seen in this
      example:</para>

    <programlisting>hint.pcm.0.vol="50"</programlisting>

    <para>This will set the volume channel to a default value of
      <literal>50</literal> when the &man.pcm.4; module is
      loaded.</para>
  </sect2>
</sect1>

<sect1 xml:id="sound-mp3">
  <!--
  <sect1info>
    <authorgroup>
      <author>
	<firstname>Chern</firstname>
	<surname>Lee</surname>
	<contrib>Contributed by in Sept 2001</contrib>
      </author>
    </authorgroup>
  </sect1info>
  -->

    <title>MP3 Audio</title>

    <para>This section describes some <acronym>MP3</acronym>
      players available for &os;, how to rip audio CD tracks, and
      how to encode and decode <acronym>MP3</acronym>s.</para>

    <sect2 xml:id="mp3-players">
      <title>MP3 Players</title>

      <para>A popular graphical <acronym>MP3</acronym> player is
	<application>XMMS</application>.
	<application>Winamp</application>
	skins can be used with <application>XMMS</application> since
	the interface is almost identical to that of Nullsoft's
	<application>Winamp</application>.
	<application>XMMS</application> also has native plug-in
	support.</para>

      <para><application>XMMS</application> can be installed from
	the <package>multimedia/xmms</package> port
	or package.</para>

      <para><application>XMMS</application>'s interface is intuitive,
	with a playlist, graphic equalizer, and more.  Those familiar
	with <application>Winamp</application> will find
	<application>XMMS</application> simple to use.</para>

      <para>The <package>audio/mpg123</package> port
	provides an alternative, command-line <acronym>MP3</acronym>
	player.</para>

      <para><application>mpg123</application> can be run by specifying
	the sound device and the <acronym>MP3</acronym> file on the
	command line.  Assuming the audio device is
	<filename>/dev/dsp1.0</filename> and the
	<acronym>MP3</acronym> file is
	<replaceable>Foobar-GreatestHits.mp3</replaceable>, enter the
	following to play the file:</para>

      <screen>&prompt.root; <userinput>mpg123 -a /dev/dsp1.0 Foobar-GreatestHits.mp3</userinput>
High Performance MPEG 1.0/2.0/2.5 Audio Player for Layer 1, 2 and 3.
Version 0.59r (1999/Jun/15). Written and copyrights by Michael Hipp.
Uses code from various people. See 'README' for more!
THIS SOFTWARE COMES WITH ABSOLUTELY NO WARRANTY! USE AT YOUR OWN RISK!





Playing MPEG stream from Foobar-GreatestHits.mp3 ...
MPEG 1.0 layer III, 128 kbit/s, 44100 Hz joint-stereo</screen>
    </sect2>

    <sect2 xml:id="rip-cd">
      <title>Ripping CD Audio Tracks</title>

      <para>Before encoding a CD or CD track to
	<acronym>MP3</acronym>, the audio data on the CD must be
	ripped to the hard drive.  This is done by copying the raw CD
	Digital Audio (<acronym>CDDA</acronym>) data to
	<acronym>WAV</acronym> files.</para>

      <para>The <command>cdda2wav</command> tool, which is installed
	with the <package>sysutils/cdrtools</package>
	suite, is used for ripping audio information from CDs and the
	information associated with them.</para>

      <para>With the audio CD in the drive, the following command can
	be issued as <systemitem class="username">root</systemitem> to rip an entire CD
	into individual (per track) <acronym>WAV</acronym>
	files:</para>

      <screen>&prompt.root; <userinput>cdda2wav -D 0,1,0 -B</userinput></screen>

      <para>The <option>-D <replaceable>0,1,0</replaceable></option>
	indicates the SCSI device <filename>0,1,0</filename>,
	which corresponds to the output of <command>cdrecord
	  -scanbus</command>.</para>

      <para><application>cdda2wav</application> will support ATAPI
	(IDE) CDROM drives.  To rip from an IDE drive, specify the
	device name in place of the SCSI unit numbers.  For example,
	to rip track 7 from an IDE drive:</para>

      <screen>&prompt.root; <userinput>cdda2wav -D /dev/acd0 -t 7</userinput></screen>

      <para>To rip individual tracks, make use of the
	<option>-t</option> as shown:</para>

      <screen>&prompt.root; <userinput>cdda2wav -D 0,1,0 -t 7</userinput></screen>

      <para>This example rips track seven of the audio CDROM.  To rip
	a range of tracks, such as track one to seven, specify a
	range:</para>

      <screen>&prompt.root; <userinput>cdda2wav -D 0,1,0 -t 1+7</userinput></screen>

      <para>&man.dd.1; can also be used to extract audio tracks on
	ATAPI drives, as described in <xref linkend="duplicating-audiocds"/>.</para>

    </sect2>

    <sect2 xml:id="mp3-encoding">
      <title>Encoding MP3s</title>

      <para>
	<application>Lame</application> is a popular
	<acronym>MP3</acronym> encoder which can be installed from the
	<package>audio/lame</package> port.  Due to
	licensing restrictions, a package is not available.</para>

      <para>The following command will convert the ripped
	<acronym>WAV</acronym> files
	<filename>audio01.wav</filename>
	to
	<filename>audio01.mp3</filename>:</para>

      <screen>&prompt.root; <userinput>lame -h -b 128 \
--tt "Foo Song Title" \
--ta "FooBar Artist" \
--tl "FooBar Album" \
--ty "2001" \
--tc "Ripped and encoded by Foo" \
--tg "Genre" \
audio01.wav audio01.mp3</userinput></screen>

      <para>128&nbsp;kbits is a standard <acronym>MP3</acronym>
	bitrate.  The 160 and 192 bitrates provide higher quality.
	The higher the bitrate, the larger the size of the resulting
	<acronym>MP3</acronym>.  <option>-h</option> turns on the
	<quote>higher quality but a little slower</quote> mode.  The
	options beginning with <option>--t</option> indicate ID3 tags,
	which usually contain song information, to be embedded within
	the <acronym>MP3</acronym> file.  Additional encoding options
	can be found in the <application>lame</application> manual
	page.</para>
    </sect2>

    <sect2 xml:id="mp3-decoding">
      <title>Decoding MP3s</title>

      <para>In order to burn an audio CD from <acronym>MP3</acronym>s,
	they must first be converted to a non-compressed
	<acronym>WAV</acronym> format.  Both
	<application>XMMS</application> and
	<application>mpg123</application> support the output of
	<acronym>MP3</acronym> to an uncompressed file format.</para>

      <para>Writing to Disk in <application>XMMS</application>:</para>

      <procedure>
	<step>
	  <para>Launch <application>XMMS</application>.</para>
	</step>

	<step>
	  <para>Right-click the window to bring up the
	    <application>XMMS</application> menu.</para>
	</step>

	<step>
	  <para>Select <literal>Preferences</literal> under
	    <literal>Options</literal>.</para>
	</step>

	<step>
	  <para>Change the Output Plugin to <quote>Disk Writer
	      Plugin</quote>.</para>
	</step>

	<step>
	  <para>Press <literal>Configure</literal>.</para>
	</step>

	<step>
	  <para>Enter or browse to a directory to write the
	    uncompressed files to.</para>
	</step>

	<step>
	  <para>Load the <acronym>MP3</acronym> file into
	    <application>XMMS</application> as usual, with volume at
	    100% and EQ settings turned off.</para>
	</step>

	<step>
	  <para>Press <literal>Play</literal>.  The
	    <application>XMMS</application> will appear as if it is
	    playing the <acronym>MP3</acronym>, but no music will be
	    heard.  It is actually playing the <acronym>MP3</acronym>
	    to a file.</para>
	</step>

	<step>
	  <para>When finished, be sure to set the default Output
	    Plugin back to what it was before in order to listen to
	    <acronym>MP3</acronym>s again.</para>
	</step>
      </procedure>

      <para>Writing to stdout in
	<application>mpg123</application>:</para>

      <procedure>
	<step>
	  <para>Run <command>mpg123 -s
	      audio01.mp3 &gt;
	      audio01.pcm</command></para>
	</step>
      </procedure>

      <para><application>XMMS</application> writes a file in the
	<acronym>WAV</acronym> format, while
	<application>mpg123</application> converts the
	<acronym>MP3</acronym> into raw PCM audio data.  Both of these
	formats can be used with <application>cdrecord</application>
	to create audio CDs, whereas &man.burncd.8; requires a raw
	Pulse-Code Modulation (<acronym>PCM</acronym>).  When using
	<acronym>WAV</acronym> files, there will be a small tick
	sound at the beginning of each track.  This sound is the
	header of the <acronym>WAV</acronym> file.  One can remove the
	header with <application>SoX</application>, which can be
	installed from the <package>audio/sox</package> port or package:</para>

      <screen>&prompt.user; <userinput>sox -t wav -r 44100 -s -w -c 2 track.wav track.raw</userinput></screen>

      <para>Refer to <xref linkend="creating-cds"/> for more
	information on using a CD burner in &os;.</para>
    </sect2>
  </sect1>

  <sect1 xml:id="video-playback">
    <!--
    <sect1info>
      <authorgroup>
	<author>
	  <firstname>Ross</firstname>
	  <surname>Lippert</surname>
	  <contrib>Contributed by in June 2002</contrib>
	</author>
      </authorgroup>
    </sect1info>
    -->

    <title>Video Playback</title>

    <para>Before configuring video playback, determine the model and
      chipset of the video card.  While
      <application>&xorg;</application> supports a wide variety of
      video cards, not all provide good playback performance.  To
      obtain a list of extensions supported by the
      <application>&xorg;</application> server using the card, run
      <command>xdpyinfo</command> while
      <application>&xorg;</application> is running.</para>

    <para>It is a good idea to have a short MPEG test file for
      evaluating various players and options.  Since some
      <acronym>DVD</acronym> applications look for
      <acronym>DVD</acronym> media in <filename>/dev/dvd</filename> by default, or have this
      device name hardcoded in them, it might be useful to make a
      symbolic links to the proper device:</para>

    <screen>&prompt.root; <userinput>ln -sf /dev/cd0 /dev/dvd</userinput></screen>

    <para>Due to the nature of &man.devfs.5;, manually created links
      will not persist after a system reboot.  In order to recreate
      the symbolic link automatically when the system boots, add the
      following line to <filename>/etc/devfs.conf</filename>:</para>

    <programlisting>link cd0 dvd</programlisting>

    <para><acronym>DVD</acronym> decryption invokes certain functions
      that require write permission to the <acronym>DVD</acronym>
      device.</para>

    <para>To enhance the shared memory
      <application>&xorg;</application> interface, it is
      recommended to increase the values of these &man.sysctl.8;
      variables:</para>

    <programlisting>kern.ipc.shmmax=67108864
kern.ipc.shmall=32768</programlisting>

  <sect2 xml:id="video-interface">
    <title>Determining Video Capabilities</title>

    <indexterm><primary>XVideo</primary></indexterm>
    <indexterm><primary>SDL</primary></indexterm>
    <indexterm><primary>DGA</primary></indexterm>

    <para>There are several possible ways to display video under
      <application>&xorg;</application> and what works is largely
      hardware dependent.  Each method described below will have
      varying quality across different hardware.</para>

    <para>Common video interfaces include:</para>

    <orderedlist>
      <listitem>
	<para><application>&xorg;</application>: normal output using
	  shared memory.</para>
      </listitem>

      <listitem>
	<para>XVideo: an extension to the
	  <application>&xorg;</application> interface which
	  allows video to be directly displayed in drawable objects
	  through a special acceleration.  This extension provides
	  good quality playback even on low-end machines.  The next
	  section describes how to determine if this extension is
	  running.</para>
      </listitem>

      <listitem>
	<para><acronym>SDL</acronym>: the Simple Directmedia Layer is
	  a porting layer for many operating systems, allowing
	  cross-platform applications to be developed which make
	  efficient use of sound and graphics.  <acronym>SDL</acronym>
	  provides a low-level abstraction to the hardware which can
	  sometimes be more efficient than the
	  <application>&xorg;</application> interface.  On &os;,
	  <acronym>SDL</acronym> can be installed using the <package>devel/sdl20</package> package or
	  port.</para>
      </listitem>

      <listitem>
	<para><acronym>DGA</acronym>: the Direct Graphics Access is an
	  <application>&xorg;</application> extension which allows a
	  program to bypass the <application>&xorg;</application>
	  server and directly alter the framebuffer.  Because it
	  relies on a low level memory mapping, programs using it must
	  be run as <systemitem class="username">root</systemitem>.  The
	  <acronym>DGA</acronym> extension can be tested and
	  benchmarked using &man.dga.1;.  When <command>dga</command>
	  is running, it changes the colors of the display whenever a
	  key is pressed.  To quit, press <keycap>q</keycap>.</para>
      </listitem>

      <listitem>
	<para>SVGAlib: a low level console graphics layer.</para>
      </listitem>
    </orderedlist>

    <sect3 xml:id="video-interface-xvideo">
      <title>XVideo</title>

      <para>To check whether this extension is running, use
	<command>xvinfo</command>:</para>

      <screen>&prompt.user; <userinput>xvinfo</userinput></screen>

      <para>XVideo is supported for the card if the result is similar
	to:</para>

      <screen>X-Video Extension version 2.2
  screen #0
  Adaptor #0: "Savage Streams Engine"
    number of ports: 1
    port base: 43
    operations supported: PutImage
    supported visuals:
      depth 16, visualID 0x22
      depth 16, visualID 0x23
    number of attributes: 5
      "XV_COLORKEY" (range 0 to 16777215)
              client settable attribute
              client gettable attribute (current value is 2110)
      "XV_BRIGHTNESS" (range -128 to 127)
              client settable attribute
              client gettable attribute (current value is 0)
      "XV_CONTRAST" (range 0 to 255)
              client settable attribute
              client gettable attribute (current value is 128)
      "XV_SATURATION" (range 0 to 255)
              client settable attribute
              client gettable attribute (current value is 128)
      "XV_HUE" (range -180 to 180)
              client settable attribute
              client gettable attribute (current value is 0)
    maximum XvImage size: 1024 x 1024
    Number of image formats: 7
      id: 0x32595559 (YUY2)
        guid: 59555932-0000-0010-8000-00aa00389b71
        bits per pixel: 16
        number of planes: 1
        type: YUV (packed)
      id: 0x32315659 (YV12)
        guid: 59563132-0000-0010-8000-00aa00389b71
        bits per pixel: 12
        number of planes: 3
        type: YUV (planar)
      id: 0x30323449 (I420)
        guid: 49343230-0000-0010-8000-00aa00389b71
        bits per pixel: 12
        number of planes: 3
        type: YUV (planar)
      id: 0x36315652 (RV16)
        guid: 52563135-0000-0000-0000-000000000000
        bits per pixel: 16
        number of planes: 1
        type: RGB (packed)
        depth: 0
        red, green, blue masks: 0x1f, 0x3e0, 0x7c00
      id: 0x35315652 (RV15)
        guid: 52563136-0000-0000-0000-000000000000
        bits per pixel: 16
        number of planes: 1
        type: RGB (packed)
        depth: 0
        red, green, blue masks: 0x1f, 0x7e0, 0xf800
      id: 0x31313259 (Y211)
        guid: 59323131-0000-0010-8000-00aa00389b71
        bits per pixel: 6
        number of planes: 3
        type: YUV (packed)
      id: 0x0
        guid: 00000000-0000-0000-0000-000000000000
        bits per pixel: 0
        number of planes: 0
        type: RGB (packed)
        depth: 1
        red, green, blue masks: 0x0, 0x0, 0x0</screen>

      <para>The formats listed, such as YUV2 and YUV12, are not
	present with every implementation of XVideo and their absence
	may hinder some players.</para>

      <para>If the result instead looks like:</para>

      <screen>X-Video Extension version 2.2
screen #0
no adaptors present</screen>

      <para>XVideo is probably not supported for the card.  This means
	that it will be more difficult for the display to meet the
	computational demands of rendering video, depending on the
	video card and processor.</para>
    </sect3>
  </sect2>

  <sect2 xml:id="video-ports">
    <title>Ports and Packages Dealing with Video</title>

    <indexterm><primary>video ports</primary></indexterm>
    <indexterm><primary>video packages</primary></indexterm>

    <para>This section introduces some of the software available from
      the &os; Ports Collection which can be used for video
      playback.</para>

    <sect3 xml:id="video-mplayer">
      <title><application>MPlayer</application> and
	<application>MEncoder</application></title>

      <para><application>MPlayer</application> is a command-line video
	player with an optional graphical interface which aims to
	provide speed and flexibility.  Other graphical front-ends to
	<application>MPlayer</application> are available from the &os;
	Ports Collection.</para>

      <indexterm><primary>MPlayer</primary></indexterm>

      <para><application>MPlayer</application> can be installed using
	the <package>multimedia/mplayer</package>
	package or port.  Several compile options are available and a
	variety of hardware checks occur during the build process.
	For these reasons, some users prefer to build the port rather
	than install the package.</para>

      <para>When compiling the port, the menu options should be
	reviewed to determine the type of support to compile into the
	port.  If an option is not selected,
	<application>MPlayer</application> will not be able to
	display that type of video format.  Use the arrow keys and
	spacebar to select the required formats.  When finished,
	press <keycap>Enter</keycap> to continue the port compile
	and installation.</para>

      <para>By default, the package or port will build the
	<command>mplayer</command> command line utility and the
	<command>gmplayer</command> graphical utility.  To encode
	videos, compile the <package>multimedia/mencoder</package> port.  Due to
	licensing restrictions, a package is not available for
	<application>MEncoder</application>.</para>

      <para>The first time <application>MPlayer</application> is run,
	it will create <filename>~/.mplayer</filename> in the user's home
	directory.  This subdirectory contains default versions of
	the user-specific configuration files.</para>

      <para>This section describes only a few common uses.  Refer to
	mplayer(1) for a complete description of its numerous
	options.</para>

      <para>To play the file
	<filename>testfile.avi</filename>,
	specify the video interfaces with <option>-vo</option>, as
	seen in the following examples:</para>

      <screen>&prompt.user; <userinput>mplayer -vo xv testfile.avi</userinput></screen>

      <screen>&prompt.user; <userinput>mplayer -vo sdl testfile.avi</userinput></screen>

      <screen>&prompt.user; <userinput>mplayer -vo x11 testfile.avi</userinput></screen>

      <screen>&prompt.root; <userinput>mplayer -vo dga testfile.avi</userinput></screen>

      <screen>&prompt.root; <userinput>mplayer -vo 'sdl:dga' testfile.avi</userinput></screen>

      <para>It is worth trying all of these options, as their
	relative performance depends on many factors and will vary
	significantly with hardware.</para>

      <para>To play a <acronym>DVD</acronym>, replace
	<filename>testfile.avi</filename>
	with <option>dvd://<replaceable>N</replaceable> -dvd-device
	 <replaceable>DEVICE</replaceable></option>, where
	<replaceable>N</replaceable> is the title number to play and
	<replaceable>DEVICE</replaceable> is the device node for the
	<acronym>DVD</acronym>.  For example, to play title 3 from
	<filename>/dev/dvd</filename>:</para>

      <screen>&prompt.root; <userinput>mplayer -vo xv dvd://3 -dvd-device /dev/dvd</userinput></screen>

      <note>
	<para>The default <acronym>DVD</acronym> device can be defined
	  during the build of the <application>MPlayer</application>
	  port by including the
	  <varname>WITH_DVD_DEVICE=/path/to/desired/device</varname>
	  option.  By default, the device is
	  <filename>/dev/cd0</filename>.  More details can be found in
	  the port's <filename>Makefile.options</filename>.</para>
      </note>

      <para>To stop, pause, advance, and so on, use a keybinding.  To
	see the list of keybindings, run <command>mplayer
	  -h</command> or read mplayer(1).</para>

      <para>Additional playback options include <option>-fs
	  -zoom</option>, which engages fullscreen mode, and
	<option>-framedrop</option>, which helps performance.</para>

      <para>Each user can add commonly used options to their
	<filename>~/.mplayer/config</filename> like so:</para>

      <programlisting>vo=xv
fs=yes
zoom=yes</programlisting>

      <para><command>mplayer</command> can be used to rip a
	<acronym>DVD</acronym> title to a <filename>.vob</filename>.
	To dump the second title from a <acronym>DVD</acronym>:</para>

      <screen>&prompt.root; <userinput>mplayer -dumpstream -dumpfile out.vob dvd://2 -dvd-device /dev/dvd</userinput></screen>

      <para>The output file, <filename>out.vob</filename>, will be in
	<acronym>MPEG</acronym> format.</para>

      <para>Anyone wishing to obtain a high level of expertise with
	&unix; video should consult <link xlink:href="http://www.mplayerhq.hu/DOCS/">mplayerhq.hu/DOCS</link>
	as it is technically informative.  This documentation should
	be considered as required reading before submitting any bug
	reports.</para>

      <indexterm>
	<primary>mencoder</primary>
      </indexterm>

      <para>Before using <command>mencoder</command>, it is a good
	idea to become familiar with the options described at
	<link xlink:href="http://www.mplayerhq.hu/DOCS/HTML/en/mencoder.html">mplayerhq.hu/DOCS/HTML/en/mencoder.html</link>.
	There are innumerable ways to improve quality, lower bitrate,
	and change formats, and some of these options may make the
	difference between good or bad performance.  Improper
	combinations of command line options can yield output files
	that are unplayable even by <command>mplayer</command>.</para>

      <para>Here is an example of a simple copy:</para>

      <screen>&prompt.user; <userinput>mencoder input.avi -oac copy -ovc copy -o output.avi</userinput></screen>

      <para>To rip to a file, use <option>-dumpfile</option> with
	<command>mplayer</command>.</para>

      <para>To convert
	<filename>input.avi</filename> to
	the MPEG4 codec with MPEG3 audio encoding, first install the
	<package>audio/lame</package> port.  Due to
	licensing restrictions, a package is not available.  Once
	installed, type:</para>

      <screen>&prompt.user; <userinput>mencoder input.avi -oac mp3lame -lameopts br=192 \
	 -ovc lavc -lavcopts vcodec=mpeg4:vhq -o output.avi</userinput></screen>

      <para>This will produce output playable by applications such as
	<command>mplayer</command> and <command>xine</command>.</para>

      <para><filename>input.avi</filename>
	can be replaced with <option>dvd://1 -dvd-device
	  /dev/dvd</option> and run as <systemitem class="username">root</systemitem> to
	re-encode a <acronym>DVD</acronym> title directly.  Since it
	may take a few tries to get the desired result, it is
	recommended to instead dump the title to a file and to work on
	the file.</para>
    </sect3>

    <sect3 xml:id="video-xine">
      <title>The <application>xine</application> Video Player</title>

      <para><application>xine</application> is a video player with a
	reusable base library and a modular executable which can be
	extended with plugins.  It can be installed using the
	<package>multimedia/xine</package> package or
	port.</para>

      <para>In practice, <application>xine</application> requires
	either a fast CPU with a fast video card, or support for the
	XVideo extension.  The <application>xine</application> video
	player performs best on XVideo interfaces.</para>

      <para>By default, the <application>xine</application> player
	starts a graphical user interface.  The menus can then be used
	to open a specific file.</para>

      <para>Alternatively, <application>xine</application> may be
	invoked from the command line
	by specifying the name of the file to play:</para>

      <screen>&prompt.user; <userinput>xine -g -p mymovie.avi</userinput></screen>

      <para>Refer to <link xlink:href="http://www.xine-project.org/faq">
	xine-project.org/faq</link> for more information and
	troubleshooting tips.</para>
    </sect3>

    <sect3 xml:id="video-ports-transcode">
      <title>The <application>Transcode</application>
	Utilities</title>

      <para><application>Transcode</application> provides a suite of
	tools for re-encoding video and audio files.
	<application>Transcode</application> can be used to merge
	video files or repair broken files using command line tools
	with stdin/stdout stream
	interfaces.</para>

      <para>In &os;, <application>Transcode</application> can be
	installed using the <package>multimedia/transcode</package> package or
	port.  Many users prefer to compile the port as it provides a
	menu of compile options for specifying the support and codecs
	to compile in.  If an option is not selected,
	<application>Transcode</application> will not be able to
	encode that format.  Use the arrow keys and spacebar to select
	the required formats.  When finished, press
	<keycap>Enter</keycap> to continue the port compile and
	installation.</para>

      <para>This example demonstrates how to convert a DivX file into
	a PAL MPEG-1 file (PAL VCD):</para>

      <screen>&prompt.user; <userinput>transcode -i
input.avi -V --export_prof vcd-pal -o output_vcd</userinput>
&prompt.user; <userinput>mplex -f 1 -o output_vcd.mpg output_vcd.m1v output_vcd.mpa</userinput></screen>

      <para>The resulting <acronym>MPEG</acronym> file,
	<filename>output_vcd.mpg</filename>,
	is ready to be played with <application>MPlayer</application>.
	The file can be burned on a <acronym>CD</acronym> media to
	create a video <acronym>CD</acronym> using a utility such as
	  <package>multimedia/vcdimager</package> or <package>sysutils/cdrdao</package>.</para>

      <para>In addition to the manual page for
	<command>transcode</command>, refer to  <link xlink:href="http://www.transcoding.org/cgi-bin/transcode">transcoding.org/cgi-bin/transcode</link>
	for further information and examples.</para>
    </sect3>
  </sect2>
</sect1>

<sect1 xml:id="tvcard">
  <!--
  <sect1info>
    <authorgroup>
      <author>
	<firstname>Josef</firstname>
	<surname>El-Rayes</surname>
	<contrib>Original contribution by </contrib>
      </author>
    </authorgroup>
    <authorgroup>
      <author>
	<firstname>Marc</firstname>
	<surname>Fonvieille</surname>
	<contrib>Enhanced and adapted by in January 2004</contrib>
      </author>
    </authorgroup>
  </sect1info>
  -->

  <title>TV Cards</title>

  <indexterm>
    <primary>TV cards</primary>
  </indexterm>

  <para>TV cards can be used to watch broadcast or cable TV on a
    computer.  Most cards accept composite video via an
    <acronym>RCA</acronym> or S-video input and some cards include a
    <acronym>FM</acronym> radio tuner.</para>

  <para>&os; provides support for PCI-based TV cards using a
    Brooktree Bt848/849/878/879 video capture chip with the
    &man.bktr.4; driver.  This driver supports most Pinnacle PCTV
    video cards.  Before purchasing a TV card, consult &man.bktr.4; for
    a list of supported tuners.</para>

  <sect2>
    <title>Loading the Driver</title>

    <para>In order to use the card, the &man.bktr.4; driver must be
      loaded.  To automate this at boot time, add the following line
      to <filename>/boot/loader.conf</filename>:</para>

    <programlisting>bktr_load="YES"</programlisting>

      <para>Alternatively, one can statically compile support for
	the TV card into a custom kernel.  In that case, add the
	following lines to the custom kernel configuration
	file:</para>

      <programlisting>device	 bktr
device	iicbus
device	iicbb
device	smbus</programlisting>

      <para>These additional devices are necessary as the card
	components are interconnected via an I2C bus.  Then, build and
	install a new kernel.</para>

      <para>To test that the tuner is correctly detected, reboot the
	system.  The TV card should appear in the boot messages, as
	seen in this example:</para>

      <programlisting>bktr0: &lt;BrookTree 848A&gt; mem 0xd7000000-0xd7000fff irq 10 at device 10.0 on pci0
iicbb0: &lt;I2C bit-banging driver&gt; on bti2c0
iicbus0: &lt;Philips I2C bus&gt; on iicbb0 master-only
iicbus1: &lt;Philips I2C bus&gt; on iicbb0 master-only
smbus0: &lt;System Management Bus&gt; on bti2c0
bktr0: Pinnacle/Miro TV, Philips SECAM tuner.</programlisting>

      <para>The messages will differ according to the hardware.
	If necessary, it is possible to override some of the detected
	parameters using &man.sysctl.8; or custom kernel configuration
	options.  For example, to force the tuner to a Philips
	SECAM tuner, add the following line to a custom kernel
	configuration file:</para>

      <programlisting>options OVERRIDE_TUNER=6</programlisting>

      <para>or, use &man.sysctl.8;:</para>

      <screen>&prompt.root; <userinput>sysctl hw.bt848.tuner=6</userinput></screen>

      <para>Refer to &man.bktr.4; for a description of the available
	&man.sysctl.8; parameters and kernel options.</para>
    </sect2>

    <sect2>
      <title>Useful Applications</title>

      <para>To use the TV card, install one of the following
	applications:</para>

      <itemizedlist>
	<listitem>
	  <para><package>multimedia/fxtv</package>
	    provides TV-in-a-window and image/audio/video capture
	    capabilities.</para>
	</listitem>
	<listitem>
	  <para><package>multimedia/xawtv</package>
	    is another TV application with similar features.</para>
	</listitem>
	<listitem>
	  <para><package>audio/xmradio</package>
	    provides an application for using the FM radio tuner of a
	    TV card.</para>
	</listitem>
      </itemizedlist>

      <para>More applications are available in the &os; Ports
	Collection.</para>
    </sect2>

    <sect2>
      <title>Troubleshooting</title>

      <para>If any problems are encountered with the TV card, check
	that the video capture chip and the tuner are supported by
	&man.bktr.4; and that the right configuration options were
	used.  For more support or to ask questions
	about supported TV cards, refer to the
	&a.multimedia.name; mailing list.</para>
    </sect2>
  </sect1>

  <sect1 xml:id="mythtv">
    <title>MythTV</title>

    <para>MythTV is a popular, open source Personal Video Recorder
      (<acronym>PVR</acronym>) application.  This section demonstrates
      how to install and setup MythTV on &os;.  Refer to <link xlink:href="http://www.mythtv.org/wiki/">mythtv.org/wiki</link> for
      more information on how to use MythTV.</para>

    <para>MythTV requires a frontend and a backend.  These
      components can either be installed on the same system or on
      different machines.</para>

    <para>The frontend can be installed on &os; using the <package>multimedia/mythtv-frontend</package> package
      or port.  <application>&xorg;</application> must also be
      installed and configured as described in <xref linkend="x11"/>.  Ideally, this system has a video card that
      supports X-Video Motion Compensation
      (<acronym>XvMC</acronym>) and, optionally, a Linux Infrared
      Remote Control (<acronym>LIRC</acronym>)-compatible
      remote.</para>

    <para>To install both the backend and the frontend on &os;, use
      the <package>multimedia/mythtv</package>
      package or port.  A &mysql; database server is also required
      and should automatically be installed as a dependency.
      Optionally, this system should have a tuner card and
      sufficient storage to hold recorded data.</para>

    <sect2>
      <title>Hardware</title>

      <para>MythTV uses Video for Linux (<acronym>V4L</acronym>) to
	access video input devices such as encoders and tuners.  In
	&os;, MythTV works best with <acronym>USB</acronym> DVB-S/C/T
	cards as they are well supported by the <package>multimedia/webcamd</package> package or port
	which provides a <acronym>V4L</acronym> userland application.
	Any Digital Video Broadcasting (<acronym>DVB</acronym>) card
	supported by <application>webcamd</application> should work
	with MythTV.  A list of known working cards can be found at
	<link xlink:href="http://wiki.freebsd.org/WebcamCompat">wiki.freebsd.org/WebcamCompat</link>.
	Drivers are also available for Hauppauge cards in the
	<package>multimedia/pvr250</package> and <package>multimedia/pvrxxx</package> ports, but they
	provide a non-standard driver interface that does not work
	with versions of MythTV greater than 0.23.  Due to licensing
	restrictions, no packages are available and these two ports
	must be compiled.</para>

      <para>The <link xlink:href="http://wiki.freebsd.org/HTPC">wiki.freebsd.org/HTPC</link>
	page contains a list of all available <acronym>DVB</acronym>
	drivers.</para>
    </sect2>

    <sect2>
      <title>Setting up the MythTV Backend</title>

      <para>To install MythTV using the port:</para>

      <screen>&prompt.root; <userinput>cd /usr/ports/multimedia/mythtv</userinput>
&prompt.root; <userinput>make install</userinput></screen>

      <para>Once installed, set up the MythTV database:</para>

      <screen>&prompt.root; <userinput>mysql -uroot -p &lt; /usr/local/share/mythtv/database/mc.sql</userinput></screen>

      <para>Then, configure the backend:</para>

      <screen>&prompt.root; <userinput>mythtv-setup</userinput></screen>

      <para>Finally, start the backend:</para>

      <screen>&prompt.root; <userinput>echo 'mythbackend_enable="YES"' &gt;&gt; /etc/rc.conf</userinput>
&prompt.root; <userinput>service mythbackend start</userinput></screen>
    </sect2>
  </sect1>

  <sect1 xml:id="scanners">
    <!--
    <sect1info>
      <authorgroup>
	<author>
	  <firstname>Marc</firstname>
	  <surname>Fonvieille</surname>
	  <contrib>Written by in August 2004</contrib>
	</author>
      </authorgroup>
    </sect1info>
    -->

    <title>Image Scanners</title>

    <indexterm>
      <primary>image scanners</primary>
    </indexterm>

    <para>In &os;, access to image scanners is provided by the
      <application>SANE</application> (Scanner Access Now Easy)
      <acronym role="Application Programming       Interface">API</acronym> available through the &os; Ports
      Collection.  <application>SANE</application> will also use
      some &os; device drivers to provide access to the scanner
      hardware.</para>

    <para>&os; supports both SCSI and USB scanners.  Be sure the
      scanner is supported by <application>SANE</application> prior
      to performing any configuration.  Refer to the <link xlink:href="http://www.sane-project.org/sane-supported-devices.html">
      supported devices list</link> for more information about
      supported scanners.</para>

    <sect2>
      <title>Kernel Configuration</title>

      <para>Both SCSI and USB interfaces are supported.  Depending
	upon the scanner interface, different device drivers are
	required.</para>

      <sect3 xml:id="scanners-kernel-usb">
	<title>USB Interface</title>

	<para>The <filename>GENERIC</filename> kernel by default
	  includes the device drivers needed to support USB scanners.
	  Users with a custom kernel should ensure that the following
	  lines are present in the custom kernel configuration
	  file:</para>

	<programlisting>device usb
device uhci
device ohci
device ehci</programlisting>

	<para>Plug in the USB scanner.  Use &man.dmesg.8; to determine
	  whether the scanner appears in the system message
	  buffer:</para>

	<screen>ugen0.2: &lt;EPSON&gt; at usbus0</screen>

	<para>These messages indicate that the scanner is using
	  either <filename>/dev/ugen0.2</filename> or
	  <filename>/dev/uscanner0</filename>, depending on the &os;
	  version.  For this example, a
	  &epson.perfection;&nbsp;1650 USB scanner was used.</para>
      </sect3>

      <sect3>
	<title>SCSI Interface</title>

	<para>If the scanner uses a SCSI interface, it is important to
	  know which SCSI controller board it will use.  Depending
	  upon the SCSI chipset, a custom kernel configuration file
	  may be needed.  The <filename>GENERIC</filename> kernel
	  supports the most common SCSI controllers.  Refer to
	  <filename>/usr/src/sys/conf/NOTES</filename> to determine
	  the correct line to add to a custom kernel configuration
	  file.  In addition to the SCSI adapter driver, the following
	  lines are needed in the kernel configuration file:</para>

	<programlisting>device scbus
device pass</programlisting>

	<para>Verify that the device is displayed in the system
	  message buffer:</para>

	<screen>pass2 at aic0 bus 0 target 2 lun 0
pass2: &lt;AGFA SNAPSCAN 600 1.10&gt; Fixed Scanner SCSI-2 device
pass2: 3.300MB/s transfers</screen>

	<para>If the scanner was not powered-on at system boot, it
	  is still possible to manually force the detection by
	  performing a SCSI bus scan with the &man.camcontrol.8;
	  command:</para>

	<screen>&prompt.root; <userinput>camcontrol rescan all</userinput>
Re-scan of bus 0 was successful
Re-scan of bus 1 was successful
Re-scan of bus 2 was successful
Re-scan of bus 3 was successful</screen>

	<para>The scanner should now appear in the SCSI devices
	  list:</para>

	<screen>&prompt.root; <userinput>camcontrol devlist</userinput>
&lt;IBM DDRS-34560 S97B&gt;              at scbus0 target 5 lun 0 (pass0,da0)
&lt;IBM DDRS-34560 S97B&gt;              at scbus0 target 6 lun 0 (pass1,da1)
&lt;AGFA SNAPSCAN 600 1.10&gt;           at scbus1 target 2 lun 0 (pass3)
&lt;PHILIPS CDD3610 CD-R/RW 1.00&gt;     at scbus2 target 0 lun 0 (pass2,cd0)</screen>

	<para>Refer to &man.scsi.4; and &man.camcontrol.8; for more
	  details about SCSI devices on &os;.</para>
      </sect3>
    </sect2>

    <sect2>
      <title>SANE Configuration</title>

      <para>The <application>SANE</application> system is split in two
	parts: the backends (<package>graphics/sane-backends</package>) and the
	frontends (<package>graphics/sane-frontends</package>).  The
	backends provide access to the scanner.  The
	<application>SANE</application>'s <link xlink:href="http://www.sane-project.org/sane-supported-devices.html">supported
	devices</link> list specifies which backend will support the
	image scanner.  The correct backend is needed in order to use
	the scanner.  The frontends provide the graphical scanning
	interface, <application>xscanimage</application>.</para>

      <para>After installing the <package>graphics/sane-backends</package> port or
	package, use <command>sane-find-scanner</command> to check the
	scanner detection by the
	<application>SANE</application> system:</para>

      <screen>&prompt.root; <userinput>sane-find-scanner -q</userinput>
found SCSI scanner "AGFA SNAPSCAN 600 1.10" at /dev/pass3</screen>

      <para>The output should show the interface type of the scanner
	and the device node used to attach the scanner to the system.
	The vendor and the product model may or may not appear.</para>

      <note>
	<para>Some USB scanners require firmware to be loaded.  Refer
	  to &man.sane-find-scanner.1; and &man.sane.7; for
	  details.</para>
      </note>

      <para>Next, check if the scanner will be identified by a
	scanning frontend.  By default, the
	<application>SANE</application> backends come with a command
	line tool called &man.scanimage.1;.  This command can be used
	to list the devices and perform an image acquisition.  Use
	<option>-L</option> to list the scanner devices:</para>

      <screen>&prompt.root; <userinput>scanimage -L</userinput>
device `snapscan:/dev/pass3' is a AGFA SNAPSCAN 600 flatbed scanner</screen>

      <para>Here is the output for the USB scanner used in <xref linkend="scanners-kernel-usb"/>:</para>

      <screen>&prompt.root; <userinput>scanimage -L</userinput>
device 'epson2:libusb:/dev/usb:/dev/ugen0.2' is a Epson GT-8200 flatbed scanner</screen>

      <para>In this output,
	<literal>'epson2:libusb:/dev/usb:/dev/ugen0.2'</literal> is
	the backend name (<literal>epson2</literal>) and the device
	node (<literal>/dev/ugen0.2</literal>) used by the
	scanner.</para>

      <note>
	<para>No output or a message saying that no scanners were
	  identified indicates that &man.scanimage.1; is unable to
	  identify the scanner.  If this happens, edit the backend
	  configuration file in <filename>/usr/local/etc/sane.d/</filename>
	  and define the scanner device used.</para>

	<para>In the above example, the USB scanner is perfectly
	  detected and working.</para>

	<para>To determine if the scanner is correctly
	  identified:</para>

	<screen>&prompt.root; <userinput>scanimage -L</userinput>

No scanners were identified. If you were expecting something different,
check that the scanner is plugged in, turned on and detected by the
sane-find-scanner tool (if appropriate). Please read the documentation
which came with this software (README, FAQ, manpages).</screen>

      <para>Since the scanner is not identified, edit
	<filename>/usr/local/etc/sane.d/epson2.conf</filename>.  In
	this example, the scanner model is
	&epson.perfection;&nbsp;1650 and it uses the
	<literal>epson2</literal> backend.  When editing, read the
	help comments in the backend configuration file.  Line
	changes are simple: comment out all lines that have the
	wrong interface for the scanner.  In this example, comment
	out all lines starting with the word <literal>scsi</literal>
	as the scanner uses the USB interface.  Then, at the end
	of the file, add a line specifying the interface and the
	device node used.  In this case, add the following
	line:</para>

      <programlisting>usb /dev/uscanner0</programlisting>

      <para>Save the edits and verify that the scanner is
	identified:</para>

      <screen>&prompt.root; <userinput>scanimage -L</userinput>
device `epson:/dev/uscanner0' is a Epson GT-8200 flatbed scanner</screen>

      <para>The <literal>`epson:/dev/uscanner0'</literal> field now
	gives the right backend name and the device node.</para>
    </note>

    <para>Once <command>scanimage -L</command> sees the scanner, the
      configuration is complete and the device is now ready to
      scan.</para>

    <para>While &man.scanimage.1; can be used to perform an image
      acquisition from the command line, it is often preferable to
      use a graphical interface to perform image scanning.  The
      <package>graphics/sane-frontends</package>
      package or port installs a simple but efficient graphical
      interface, <application>xscanimage</application>.</para>

    <para><application>Xsane</application>, which is installed with
      the <package>graphics/xsane</package> package
      or port, is another popular graphical scanning frontend.  It
      offers advanced features such as various scanning modes, color
      correction, and batch scans.  Both of these applications are
      usable as a <application>GIMP</application> plugin.</para>
  </sect2>

  <sect2>
    <title>Giving Other Users Access to the Scanner</title>

    <para>In order to have access to the scanner, a user needs
      read and write permissions to the device node used by the
      scanner.  In the previous example, the USB scanner uses the
      device node <filename>/dev/ugen0.2</filename> which is really a
      symlink to the real device node
      <filename>/dev/usb/0.2.0</filename>.  The symlink and the device
      node are owned, respectively, by the
      <systemitem class="groupname">wheel</systemitem> and
      <systemitem class="groupname">operator</systemitem> groups.  Adding the user to
      these groups will allow access to the scanner.  However, for
      security reasons, always think twice before adding a user
      to any group, especially <systemitem class="groupname">wheel</systemitem>.  A better
      solution is to create a group to make the scanner device
      accessible to members of this group.</para>

    <para>This example creates a group called
      <systemitem class="groupname"><replaceable>usb</replaceable></systemitem> using
      &man.pw.8;:</para>

    <screen>&prompt.root; <userinput>pw groupadd usb</userinput></screen>

      <para>Then, make the <filename>/dev/ugen0.2</filename> symlink
	and the <filename>/dev/usb/0.2.0</filename> device node
	accessible to the <systemitem class="groupname">usb</systemitem> group with write
	permissions of (<literal>0660</literal> or
	<literal>0664</literal>.  All of this is done by adding the
	following lines to
	<filename>/etc/devfs.rules</filename>:</para>

      <programlisting>[system=5]
add path ugen0.2 mode 0660 group usb
add path usb/0.2.0 mode 0666 group usb</programlisting>

      <para>Finally, add the users to
	<systemitem class="groupname"><replaceable>usb</replaceable></systemitem> in order
	to allow access to the scanner:</para>

      <screen>&prompt.root; <userinput>pw groupmod usb -m joe</userinput></screen>

      <para>For more details refer to &man.pw.8;.</para>
    </sect2>
  </sect1>
</chapter>