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diff --git a/DOCS/xml/en/tvinput.xml b/DOCS/xml/en/tvinput.xml deleted file mode 100644 index 288f4b97ab..0000000000 --- a/DOCS/xml/en/tvinput.xml +++ /dev/null @@ -1,218 +0,0 @@ -<?xml version="1.0" encoding="utf-8"?> -<!-- $Revision$ --> -<chapter id="tv-input" xreflabel="TV input"> -<title>TV input</title> - -<para> -This section is about how to enable <emphasis role="bold">watching/grabbing -from V4L compatible TV tuner</emphasis>. See the man page for a description -of TV options and keyboard controls. -</para> - -<!-- ********** --> - -<sect1 id="tv-tips"> -<title>Usage tips</title> - -<para> -The full listing of the options is available on the manual page. -Here are just a few tips: - -<itemizedlist> -<listitem><para> - Make sure your tuner works with another TV software in Linux, for - example <application>XawTV</application>. -</para></listitem> -<listitem><para> - Use the <option>channels</option> option. An example: - <screen>-tv channels=26-MTV1,23-TV2</screen> - Explanation: Using this option, only the 26 and 23 channels will be usable, - and there will be a nice OSD text upon channel switching, displaying the - channel's name. Spaces in the channel name must be replaced by the - "_" character. -</para></listitem> -<listitem><para> - Choose some sane image dimensions. The dimensions of the resulting image - should be divisible by 16. -</para></listitem> -<listitem> - <para> - If you capture the video with the vertical resolution higher than half - of the full resolution (i.e. 288 for PAL or 240 for NTSC), then the - 'frames' you get will really be interleaved pairs of fields. - Depending on what you want to do with the video you may leave it in - this form, destructively deinterlace, or break the pairs apart into - individual fields. - </para> - <para> - Otherwise you'll get a movie which is distorted during - fast-motion scenes and the bitrate controller will be probably even unable - to retain the specified bitrate as the interlacing artifacts produce high - amount of detail and thus consume lot of bandwidth. You can enable - deinterlacing with <option>-vf pp=DEINT_TYPE</option>. - Usually <option>pp=lb</option> does a good job, but it can be matter of - personal preference. - See other deinterlacing algorithms in the manual and give it a try. - </para> -</listitem> -<listitem><para> - Crop out the dead space. When you capture the video, the areas at the edges - are usually black or contain some noise. These again consume lots of - unnecessary bandwidth. More precisely it's not the black areas themselves - but the sharp transitions between the black and the brighter video image - which do but that's not important for now. Before you start capturing, - adjust the arguments of the <option>crop</option> option so that all the - crap at the margins is cropped out. Again, don't forget to keep the resulting - dimensions sane. -</para></listitem> -<listitem><para> - Watch out for CPU load. It shouldn't cross the 90% boundary for most of the - time. If you have a large capture buffer, <application>MEncoder</application> - can survive an overload for few seconds but nothing more. It's better to - turn off the 3D OpenGL screensavers and similar stuff. -</para></listitem> -<listitem><para> - Don't mess with the system clock. <application>MEncoder</application> uses the - system clock for doing A/V sync. If you adjust the system clock (especially - backwards in time), <application>MEncoder</application> gets confused and you - will lose frames. This is an important issue if you are hooked to a network - and run some time synchronization software like NTP. You have to turn NTP - off during the capture process if you want to capture reliably. -</para></listitem> -<listitem><para> - Don't change the <option>outfmt</option> unless you know what you are doing - or your card/driver really doesn't support the default (YV12 colorspace). - In the older versions of <application>MPlayer</application>/ - <application>MEncoder</application> it was necessary to specify the output - format. This issue should be fixed in the current releases and - <option>outfmt</option> isn't required anymore, and the default suits the - most purposes. For example, if you are capturing into DivX using - <systemitem class="library">libavcodec</systemitem> and specify - <option>outfmt=RGB24</option> in order to increase the quality of the captured - images, the captured image will be actually later converted back into YV12 so - the only thing you achieve is a massive waste of CPU power. -</para></listitem> -<listitem><para> - There are several ways of capturing audio. You can grab the sound either using - your sound card via an external cable connection between video card and - line-in, or using the built-in ADC in the bt878 chip. In the latter case, you - have to load the <emphasis role="bold">btaudio</emphasis> driver. Read the - <filename>linux/Documentation/sound/btaudio</filename> file (in the kernel - tree, not <application>MPlayer</application>'s) for some instructions on using - this driver. -</para></listitem> -<listitem><para> - If <application>MEncoder</application> cannot open the audio device, make - sure that it is really available. There can be some trouble with the sound - servers like aRts (KDE) or ESD (GNOME). If you have a full duplex sound card - (almost any decent card supports it today), and you are using KDE, try to - check the "full duplex" option in the sound server preference menu. -</para></listitem> -</itemizedlist> -</para> -</sect1> - -<!-- ********** --> - -<sect1 id="tv-examples"> -<title>Examples</title> - -<informalexample><para> -Dummy output, to AAlib :) -<screen>mplayer -tv driver=dummy:width=640:height=480 -vo aa tv://</screen> -</para></informalexample> - -<informalexample><para> -Input from standard V4L: -<screen> -mplayer -tv driver=v4l:width=640:height=480:outfmt=i420 -vc rawi420 -vo xv tv:// -</screen> -</para></informalexample> - -<informalexample><para> -A more sophisticated example. This makes <application>MEncoder</application> -capture the full PAL image, crop the margins, and deinterlace the picture -using a linear blend algorithm. Audio is compressed with a constant bitrate -of 64kbps, using LAME codec. This setup is suitable for capturing movies. -<screen> -mencoder -tv driver=v4l:width=768:height=576 -oac mp3lame -lameopts cbr:br=64\ - -ovc lavc -lavcopts vcodec=mpeg4:vbitrate=900 \ - -vf crop=720:544:24:16,pp=lb -o <replaceable>output.avi</replaceable> tv:// -</screen> -</para></informalexample> - -<informalexample><para> -This will additionally rescale the image to 384x288 and compresses the -video with the bitrate of 350kbps in high quality mode. The vqmax option -looses the quantizer and allows the video compressor to actually reach so -low bitrate even at the expense of the quality. This can be used for -capturing long TV series, where the video quality isn't so important. -<screen> -mencoder -tv driver=v4l:width=768:height=576 \ - -ovc lavc -lavcopts vcodec=mpeg4:vbitrate=350:vhq:vqmax=31:keyint=300 \ - -oac mp3lame -lameopts cbr:br=48 -sws 1 -o <replaceable>output.avi</replaceable>\ - -vf crop=720:540:24:18,pp=lb,scale=384:288 tv:// -</screen> -It's also possible to specify smaller image dimensions in the -<option>-tv</option> option and omit the software scaling but this approach -uses the maximum available information and is a little more resistant to noise. -The bt8x8 chips can do the pixel averaging only in the horizontal direction due -to a hardware limitation. -</para></informalexample> -</sect1> -</chapter> - - -<!-- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - --> - - -<chapter id="tv-teletext"> -<title>Teletext</title> - -<para> - Teletext is currently available only in <application>MPlayer</application> - for v4l and v4l2 drivers. -</para> - -<sect1 id="tv-teletext-implementation-notes"> -<title>Implementation notes</title> - -<para> -<application>MPlayer</application> supports regular text, graphics and navigation links. -Unfortunately, colored pages are not fully supported yet - all pages are shown as grayscaled. -Subtitle pages (also known as Closed Captions) are supported, too. -</para> - -<para> -<application>MPlayer</application> starts caching all teletext pages upon -starting to receive TV input, so you do not need to wait until the requested page is loaded. -</para> - -<para> -Note: Using teletext with <option>-vo xv</option> causes strange colors. -</para> -</sect1> - -<sect1 id="tv-teletext-usage"> -<title>Using teletext</title> - -<para> -To enable teletext decoding you must specify the VBI device to get teletext data -from (usually <filename>/dev/vbi0</filename> for Linux). This can be done by specifying -<option>tdevice</option> in your configuration file, like shown below: -<screen>tv=tdevice=/dev/vbi0</screen> -</para> - -<para> -You might need to specify the teletext language code for your country. -To list all available country codes use -<screen>tv=tdevice=/dev/vbi0:tlang=<replaceable>-1</replaceable></screen> -Here is an example for Russian: -<screen>tv=tdevice=/dev/vbi0:tlang=<replaceable>33</replaceable></screen> -</para> - -<para> -</para> -</sect1> - -</chapter> |