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diff --git a/Documentation/DocBook/media/dvb/intro.xml b/Documentation/DocBook/media/dvb/intro.xml deleted file mode 100644 index b5b701f5d8c2..000000000000 --- a/Documentation/DocBook/media/dvb/intro.xml +++ /dev/null @@ -1,211 +0,0 @@ -<title>Introduction</title> - -<section id="requisites"> -<title>What you need to know</title> - -<para>The reader of this document is required to have some knowledge in -the area of digital video broadcasting (DVB) and should be familiar with -part I of the MPEG2 specification ISO/IEC 13818 (aka ITU-T H.222), i.e -you should know what a program/transport stream (PS/TS) is and what is -meant by a packetized elementary stream (PES) or an I-frame.</para> - -<para>Various DVB standards documents are available from -<ulink url="http://www.dvb.org" /> and/or -<ulink url="http://www.etsi.org" />.</para> - -<para>It is also necessary to know how to access unix/linux devices and -how to use ioctl calls. This also includes the knowledge of C or C++. -</para> -</section> - -<section id="history"> -<title>History</title> - -<para>The first API for DVB cards we used at Convergence in late 1999 -was an extension of the Video4Linux API which was primarily developed -for frame grabber cards. As such it was not really well suited to be -used for DVB cards and their new features like recording MPEG streams -and filtering several section and PES data streams at the same time. -</para> - -<para>In early 2000, we were approached by Nokia with a proposal for a -new standard Linux DVB API. As a commitment to the development of -terminals based on open standards, Nokia and Convergence made it -available to all Linux developers and published it on -<ulink url="https://linuxtv.org" /> in September 2000. -Convergence is the maintainer of the Linux DVB API. Together with the -LinuxTV community (i.e. you, the reader of this document), the Linux DVB -API will be constantly reviewed and improved. With the Linux driver for -the Siemens/Hauppauge DVB PCI card Convergence provides a first -implementation of the Linux DVB API.</para> -</section> - -<section id="overview"> -<title>Overview</title> - -<figure id="stb_components"> -<title>Components of a DVB card/STB</title> -<mediaobject> -<imageobject> -<imagedata fileref="dvbstb.pdf" format="PS" /> -</imageobject> -<imageobject> -<imagedata fileref="dvbstb.png" format="PNG" /> -</imageobject> -</mediaobject> -</figure> - -<para>A DVB PCI card or DVB set-top-box (STB) usually consists of the -following main hardware components: </para> - -<itemizedlist> - <listitem> - -<para>Frontend consisting of tuner and DVB demodulator</para> - -<para>Here the raw signal reaches the DVB hardware from a satellite dish -or antenna or directly from cable. The frontend down-converts and -demodulates this signal into an MPEG transport stream (TS). In case of a -satellite frontend, this includes a facility for satellite equipment -control (SEC), which allows control of LNB polarization, multi feed -switches or dish rotors.</para> - -</listitem> - <listitem> - -<para>Conditional Access (CA) hardware like CI adapters and smartcard slots -</para> - -<para>The complete TS is passed through the CA hardware. Programs to -which the user has access (controlled by the smart card) are decoded in -real time and re-inserted into the TS.</para> - -</listitem> - <listitem> - <para>Demultiplexer which filters the incoming DVB stream</para> - -<para>The demultiplexer splits the TS into its components like audio and -video streams. Besides usually several of such audio and video streams -it also contains data streams with information about the programs -offered in this or other streams of the same provider.</para> - -</listitem> -<listitem> - -<para>MPEG2 audio and video decoder</para> - -<para>The main targets of the demultiplexer are the MPEG2 audio and -video decoders. After decoding they pass on the uncompressed audio and -video to the computer screen or (through a PAL/NTSC encoder) to a TV -set.</para> - - -</listitem> -</itemizedlist> - -<para><xref linkend="stb_components" /> shows a crude schematic of the control and data flow -between those components.</para> - -<para>On a DVB PCI card not all of these have to be present since some -functionality can be provided by the main CPU of the PC (e.g. MPEG -picture and sound decoding) or is not needed (e.g. for data-only uses -like “internet over satellite”). Also not every card or STB -provides conditional access hardware.</para> - -</section> - -<section id="dvb_devices"> -<title>Linux DVB Devices</title> - -<para>The Linux DVB API lets you control these hardware components -through currently six Unix-style character devices for video, audio, -frontend, demux, CA and IP-over-DVB networking. The video and audio -devices control the MPEG2 decoder hardware, the frontend device the -tuner and the DVB demodulator. The demux device gives you control over -the PES and section filters of the hardware. If the hardware does not -support filtering these filters can be implemented in software. Finally, -the CA device controls all the conditional access capabilities of the -hardware. It can depend on the individual security requirements of the -platform, if and how many of the CA functions are made available to the -application through this device.</para> - -<para>All devices can be found in the <constant>/dev</constant> -tree under <constant>/dev/dvb</constant>. The individual devices -are called:</para> - -<itemizedlist> -<listitem> - -<para><constant>/dev/dvb/adapterN/audioM</constant>,</para> -</listitem> -<listitem> -<para><constant>/dev/dvb/adapterN/videoM</constant>,</para> -</listitem> -<listitem> -<para><constant>/dev/dvb/adapterN/frontendM</constant>,</para> -</listitem> - <listitem> - -<para><constant>/dev/dvb/adapterN/netM</constant>,</para> -</listitem> - <listitem> - -<para><constant>/dev/dvb/adapterN/demuxM</constant>,</para> -</listitem> - <listitem> - -<para><constant>/dev/dvb/adapterN/dvrM</constant>,</para> -</listitem> - <listitem> - -<para><constant>/dev/dvb/adapterN/caM</constant>,</para></listitem></itemizedlist> - -<para>where N enumerates the DVB PCI cards in a system starting -from 0, and M enumerates the devices of each type within each -adapter, starting from 0, too. We will omit the “ -<constant>/dev/dvb/adapterN/</constant>” in the further discussion -of these devices.</para> - -<para>More details about the data structures and function calls of all -the devices are described in the following chapters.</para> - -</section> - -<section id="include_files"> -<title>API include files</title> - -<para>For each of the DVB devices a corresponding include file exists. -The DVB API include files should be included in application sources with -a partial path like:</para> - -<programlisting> - #include <linux/dvb/audio.h> -</programlisting> -<programlisting> - #include <linux/dvb/ca.h> -</programlisting> -<programlisting> - #include <linux/dvb/dmx.h> -</programlisting> -<programlisting> - #include <linux/dvb/frontend.h> -</programlisting> -<programlisting> - #include <linux/dvb/net.h> -</programlisting> -<programlisting> - #include <linux/dvb/osd.h> -</programlisting> -<programlisting> - #include <linux/dvb/video.h> -</programlisting> - -<para>To enable applications to support different API version, an -additional include file -<constant>linux/dvb/version.h</constant> exists, which defines the -constant <constant>DVB_API_VERSION</constant>. This document -describes <constant>DVB_API_VERSION 5.10</constant>. -</para> - -</section> - |
