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diff --git a/abs/core/local-website/htdocs/mythtv-doc/mythtv-HOWTO-10.html b/abs/core/local-website/htdocs/mythtv-doc/mythtv-HOWTO-10.html new file mode 100644 index 0000000..636696e --- /dev/null +++ b/abs/core/local-website/htdocs/mythtv-doc/mythtv-HOWTO-10.html @@ -0,0 +1,387 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN"> +<HTML> +<HEAD> + <META NAME="GENERATOR" CONTENT="LinuxDoc-Tools 0.9.21"> + <TITLE>Installing and using MythTV: Configuring mythfrontend.</TITLE> + <LINK HREF="mythtv-HOWTO-11.html" REL=next> + <LINK HREF="mythtv-HOWTO-9.html" REL=previous> + <LINK HREF="mythtv-HOWTO.html#toc10" REL=contents> +</HEAD> +<BODY> +<A HREF="mythtv-HOWTO-11.html">Next</A> +<A HREF="mythtv-HOWTO-9.html">Previous</A> +<A HREF="mythtv-HOWTO.html#toc10">Contents</A> +<HR> +<H2><A NAME="s10">10.</A> <A HREF="mythtv-HOWTO.html#toc10">Configuring mythfrontend.</A></H2> + +<P>Once you have completed configuration of your backend systems, the next +step is to configure the frontend client. </P> +<P>When you start mythfrontend for the first time, it will attempt to connect +to a configuration database on the local machine. If there is none, a +"Database Configuration" screen will appear, and you will need to fill in +some details. The "Host name" field needs the backend or database server's +IP address or DNS name, and the User or password fields may need to be set +to match your database user accounts. After editing those fields, press +Enter twice to write these configurations on your local machine, and attempt +to connect to the database. If you make any mistakes, the screens will pop +up again.</P> +<P>Now that mythfrontend has started up, you should have a number of +buttons/choices. Before doing anything, go to TV, then to Setup and +configure the frontend client. +<FIGURE> +<EPS FILE="stop.eps"> +<IMG SRC="stop.png"> +<CAPTION><B>NOTE</B>: You should go through the various setup screens in +mythfrontend before using any other modules to ensure that the the database +is correctly initialized.</CAPTION> +</FIGURE> +</P> +<H2><A NAME="ss10.1">10.1</A> <A HREF="mythtv-HOWTO.html#toc10.1">General</A> +</H2> + +<P>The General screen has configuration items that don't really fit anywhere +else. The first few configuration items ask you to indicate the number of +seconds to record before or after a program, which is useful if the +broadcast network or your system clock are out of sync and will help prevent +you missing the beginning or end of a program. </P> +<P>To change the value, use the left and right arrow keys to increment and +decrement the number of seconds. When you're satisfied with the result, use +the down arrow to put the input focus on the Next button or press RETURN to +continue to the next page.</P> +<P>The next page has a number of options to do with how channels are displayed +on your system. The help text will give you more information. Move the +focus to Next and press the space bar to continue.</P> +<P>The last General page sets up some final configuration items. See the help +text for more information.</P> + +<H2><A NAME="ss10.2">10.2</A> <A HREF="mythtv-HOWTO.html#toc10.2">Appearance</A> +</H2> + +<P>This set of screens is mostly concerned with how MythTV will look on your +system. From here, you can choose different themes and set the resolution +of your system.</P> + +<H2><A NAME="ss10.3">10.3</A> <A HREF="mythtv-HOWTO.html#toc10.3">Program Guide</A> +</H2> + +<P>Fairly self explanatory. Note that the alternate program guide does not +use the same font settings as defined in Appearance, so if the EPG is +unreadable this is where you make the adjustments to fonts, number of +elements displayed, etc.</P> + +<H2><A NAME="deinterlace_"></A> <A NAME="ss10.4">10.4</A> <A HREF="mythtv-HOWTO.html#toc10.4">Playback </A> + </H2> + +<P>The one configuration item which may cause problems on your system is the +"Deinterlace playback" setting. MythTV uses a linear blend algorithm for +deinterlacing, which will improve how the image looks on your screen. +Deinterlacing requires that your processor support SSE. (Streaming SIMD +Extensions, aka "MMX2"). Early Intel Celeron (those that don't use the +Coppermine 0.18um core and are usually <600MHz), Pentium Pro and Pentium II +CPUs do not have SSE, so make sure you haven't enabled deinterlacing if +your processor doesn't support it. If you enable it, and your processor +doesn't support SSE, you will get "Illegal Instruction" errors.</P> +<P>To determine if you've got SSE on an Intel processor, you can: +<BLOCKQUOTE><CODE> +<PRE> +$ cat /proc/cpuinfo +[snip] +flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca +cmov pat pse36 mmx fxsr sse +</PRE> +</CODE></BLOCKQUOTE> +</P> +<P>Notice the <B>sse</B> at the end of the line - this tells you that this +processor will be able to deinterlace correctly.</P> +<P>On an AMD processor, look for "3dnow" in the cpuinfo line; "3dnow" is AMD's +implementation of SSE instructions, so if your processor has 3dnow you +shouldn't have any issues with deinterlacing.</P> +<H3>Video Filters</H3> + +<P>MythTV provides a means of employing video filters while recording and +during playback. These filters can be used to improve or modify the video +image, including hiding the effects of an interlaced image or reducing the +impact of noise in a poor video signal. The following is a brief +introduction to introduce you to the filters that are available in MythTV +version 0.20 and higher.</P> +<H3>Applying filters</H3> + +<P>One or more filters can be included in a "filter chain". The filters to +be used are identified in a "filter string". A filter string is a group of +filter names and parameters separated by commas. To include parameters, the +filter name is followed by "=" and the parameter information. There should +be no spaces in the filter string. Here is an example filter string:</P> +<P>With parameters: <CODE>kerneldeint=10:1,denoise3d=12</CODE></P> +<P>Without: <CODE>kerneldeint,denoise3d</CODE></P> +<P>Recording filters are set for each individual channel. These may be used +when encoding in software (MPEG-4, RTjpeg) but do not apply when using a +capture card with hardware encoding such as those supported by the ivtv +driver, DVB, HDTV or MJPEG cards. You can run MythTV's "setup" program and +select the "Channel Editor". On the first page for each channel, you can +enter a filter string in the box titled "Video filters". If you are running +"mythweb" on your web server, you can click on "Settings" then "Channels" +and enter filter strings in the "videofilters" column.</P> +<P>Playback filters are per-host and apply to any recording you watch from the +frontend where filters have been applied. Playback filtering can only +work with software decoding so the viaslice, xvmc, and ivtv outputs ignore +filters entirely. From "mythfrontend" go to Setup->TV Settings->Playback. +Enter your filter string in the box titled "Custom Filters".</P> + +<H3>Currently Available Filters</H3> + +<P>"Deinterlace Playback" checkbox.</P> +<P>This implements special behavior needed for the "bobdeint" filter but can +also be used to choose any of the deinterlace filters. If you prefer, you +may leave this unchecked and include any of the deinterlace filters, other +than "bobdeint", in your custom filter chain.</P> +<P>o The "invert" filter</P> +<P>Invert ignores any parameters and inverts the pixel values of the video +frames. In other words, a negative image. This would rarely be useful but +may be a good example to verify that your filter strings take effect.</P> +<P>o The "linearblend" filter</P> +<P>It is a simple deinterlacing filter that ignores parameters and works by +blending adjacent lines. It replaces combing in interlaced video with a +less distracting "ghost" image.</P> +<P>o The "bobdeint" filter</P> +<P>This filter splits the interlaced image into two separate fields that +can be line doubled then displayed at twice the frame rate. If the +display is at the same refresh rate as the recording (59.92Hz NTSC or +50Hz PAL) this will cause each refresh to show objects in motion in +a new position with no jagged edges. However, if the display is not +synchronous, it will cause flickering or the appearance of the picture +moving up and down by one line.</P> +<P> +<FIGURE> +<EPS FILE="stop.eps"> +<IMG SRC="stop.png"> +<CAPTION><B>NOTE</B>: This filter requires the frame rate to be doubled +and therefore can only be used with the "Deinterlace Playback" checkbox. +Do not include this in your filter chain.</CAPTION> +</FIGURE> +</P> +<P>o The "kerneldeint" filter</P> +<P>Kerneldeint is a more complex deinterlacing filter which applies a filter +kernel using input from several lines. It generally removes combing without +a "ghost" image, sometimes leaving a faint outline of the image from the +other field. It is considered to be less distracting to watch than +linearblend or no filter at all. It accepts one or two integer parameters +separated by a colon.</P> +<P>The first parameter is the filter threshold and defaults to 12. Adjacent +lines differing by more than the threshold value are filtered. The second +option defaults to 0. If set to a non-zero value, it will cause the filter +to skip chroma, and filter only the luminance. It may be useful on some +capture cards which do not capture the chroma fields of interlaced video +correctly.</P> +<P>o The "onefield" filter</P> +<P>This is a simple one-field deinterlacing filter that uses only one field of +the interlaced video. By default it keeps the top field, though passing the +parameter "bottom" will cause it to keep the bottom field instead.</P> +<P>This filter is primarily useful for those who display 1080i HDTV signals +with a video mode that has 540 pixels vertically. The advantage over other +deinterlacing filters is that scenes with motion never show combing or +ghosting.</P> +<P>o The "adjust" filter</P> +<P>This filter adjusts the digital values for luma and chroma to ensure that +they will fall within the ranges specified in the ITU-R601 standard. By +default, this corrects a known problem for the luma range used by bt8x8 +chips which causes video to look washed out. If parameters are passed, there +need to be exactly six. However, passing a single parameter of "-1" will +disable the filter.</P> +<P>1: luma minimum input value (int) +2: luma maximum input value (int) +3: luma gamma correction (float) +4: chroma minimum input value (int) +5: chroma maximum input value (int) +6: chroma gamma correction (float)</P> +<P>The default bt8x8 correction values are equivalent to +"16:253:1.0:2:253:1.0". Output ranges are fixed at ITU-R601 values (16-235 +luma, 16-240 chroma).</P> +<P><B>NOTE</B>: If it is not already specified in the filter chain, this +filter will be automatically applied when recording with the "bttv" driver.</P> +<P>o The "quickdnr" filter</P> +<P>A fast temporal denoiser. This can take 1, 2 or 4 parameters, each being a +value from "0" for the least filtering to "255" for the greatest filtering. +With one parameter, the filter will compute the values it should use for all +of its variables. Two parameters will set the filter strength for luma and +chroma independently. If you are interested in how the algorithm works, you +may examine the source code to see how four parameter are used.</P> +<P>o The "denoise3d" filter</P> +<P>A slower denoiser that applies a spatial and temporal low-pass filter. The +spatial filter can remove some noise that quickdnr can't, but a more +powerful CPU is needed. This filter accepts 3 float parameters:</P> +<P> +<UL> +<LI>luma spatial filter strength</LI> +<LI>chroma spatial filter strength</LI> +<LI>luma temporal filter strength</LI> +</UL> +</P> +<P>Reasonable defaults will be selected for omitted parameters. The chroma +temporal filter strength is calculated from the other filter strengths.</P> +<P>o The "crop" filter</P> +<P>Covers edges of video with black bars. This helps improve video quality +when the edges of the frame are distorted. By default, this removes 16 +pixels from each edge. This can optionally take four parameters representing +top:left:bottom:right. The number times 16 is the number of pixels to remove +so, for example, the default is "=1:1:1:1".</P> +<P>o The "forceyv12" and "forceyuv422p" filters</P> +<P>These force the filter manager to use the given format. You can use one of +these at the head of a filter chain to change the capture format. The most +likely use would be forceyuv422p to use YUV422P capture on cards with known +chroma interlacing problems with YV12.</P> +<P>There are some filters included in the MythTV source code that should +not be used:</P> +<P>o The "forcergb24" and "forceargb32" filters</P> +<P>The two RGB formats should not be used because there is no conversion filter +for them yet.</P> +<P>o The "convert" filter</P> +<P>It exists but don't use it. The filter manager uses this filter +automatically when it is unable to match the input/output formats of two +adjacent filters.</P> +<P>o The "postprocess" filter</P> +<P>While this exists in MythTV source code, it is currently not recommended for +use.</P> + +<H3>Usage Considerations</H3> + +<P>There are trade-offs to consider when deciding if it would be wise to use +a filter. Any processing will modify the original image so you should assess +if the filter has made a noticeable improvement to the picture in order to +justify the impact of the processing. Adding any filter will inherently +increase CPU usage. The impact can vary dramatically depending on your CPU +type and speed, the resolution of the recording, which filters you are using +and other factors. You can only determine what is right for you through +experimentation. However, as a starting point, here are some filter strings +that you may find useful:</P> +<P>For typical broadcast stations: "kerneldeint,quickdnr"</P> +<P>For stations with poor signal quality: "linearblend,denoise3d=12"</P> +<P>For synchronous TV-out: check Deinterlace with "Bob (2x framerate)"</P> + +<H2><A NAME="Recording"></A> <A NAME="ss10.5">10.5</A> <A HREF="mythtv-HOWTO.html#toc10.5">Recording </A> +</H2> + +<P>Depending on your capture card, MythTV offers different video encoders. +The following types of hardware encoding cards are supported: +<UL> +<LI>MJPEG - Zoran-based cards; see +<A HREF="http://mjpeg.sourceforge.net">http://mjpeg.sourceforge.net</A></LI> +<LI>MPEG-2 - iTVC15/16 based cards (Hauppauge PVR-250/PVR-350); see +<A HREF="http://ivtvdriver.org">http://ivtvdriver.org</A> </LI> +<LI>HDTV - pcHDTV cards; see +<A HREF="http://pchdtv.com">http://pchdtv.com</A> and +the Air2PC-ATSC-PCI see +<A HREF="http://www.cyberestore.com/product_info.php?cPath=28&products_id=103">http://www.cyberestore.com/product_info.php?cPath=28&products_id=103</A></LI> +<LI>DVB - cards supporting DVB; see +<A HREF="http://linuxtv.org">http://linuxtv.org</A></LI> +</UL> + +For cards without hardware encoding capabilities (all cards supported by +V4L not listed above), Myth includes two methods for software encoding: +RTjpeg and MPEG-4. RTjpeg has significantly fewer CPU demands than MPEG-4, +but it generates larger files than MPEG-4 for a given recording.</P> +<P>For DVB and HDTV cards, no further configuration is required after +setting up the card using the 'mythtv-setup' program. +For all other cards, configuration is done through MythFrontend. +Selecting 'Recording Profiles' from the 'TV Settings' screen will list +the profiles currently available for the cards in your system. +Depending on what types of cards you have installed you may see: +<BLOCKQUOTE><CODE> +<PRE> +(Create new profile group) +Software Encoders +Hardware MPEG Encoders +Hardware MJPEG Encoders +Transcoders +</PRE> +</CODE></BLOCKQUOTE> + +The '(Create new profile group)' option will allow you to create custom +profiles in case you have multiple backends. Note that custom profiles +are per backend and card type. If you have 2 MPEG-2 encoders in a given +backend system, creating a custom profile will affect both of them. This +option should not be needed otherwise.</P> +<P>The 'Transcoders' group is a little different from the others. Selecting +this group will result in a menu with the following options: 'RTjpeg/MPEG-4' +and 'MPEG-2'. These types indicate what transcoder options will be used for +a given input type (i.e. the 'MPEG-2' settings would be used to transcode +MPEG-2 files into MPEG-4. The source of the MPEG-2 stream (DVB, HDTV, or +PVR-x50) does not matter. Configuration of the options is the same as below +(although any resolution settings will be ignored).</P> +<P>Selecting any of the other options will show a new screen with a list of +four profiles: +<UL> +<LI>Default</LI> +<LI>Live TV</LI> +<LI>Low Quality</LI> +<LI>High Quality</LI> +</UL> +</P> +<P>The Default profile will be used for any recording which does not otherwise +have a specific profile assigned. The 'Live TV' profile will be used when +watching TV. The remaining two profiles are available for customizing to +allow for more precise control over what quality is used for a given +program.</P> +<P>Selecting a profile will allow you to adjust the relevant options for that +card. The most significant setting is the recording resolution, but you can +also choose encoding format, audio format, and tweak other encoder specific +properties.</P> +<P> +<FIGURE> +<EPS FILE="stop.eps"> +<IMG SRC="stop.png"> +<CAPTION><B>NOTE</B>: although the width and height can be changed to almost +anything, if you start MythTV and don't see video or you get "segmentation +fault" errors, it is likely that the video4linux (v4l) subsystem did not +like the height and width parameters specified. It's best to leave the +default as-is until you're sure that MythTV is operational.</CAPTION> +</FIGURE> +</P> +<P>See the +<A HREF="mythtv-HOWTO-23.html#capture_resolution_">What capture resolution should I use? How does video work?</A> section for more information.</P> + +<H2><A NAME="ss10.6">10.6</A> <A HREF="mythtv-HOWTO.html#toc10.6">Xbox Frontends</A> +</H2> + +<P>MythTV is able to control the LED on the Xbox to indicate backend +recording status. </P> +<P>To control the LED, you will need the <B>blink</B> program from the +xbox-linux project, which is installed as <CODE>/bin/led</CODE> on GentooX. On +Xebian (the new Ed's Debian) you must install it yourself. On other +distributions it may or may not be installed as a program called +<B>blink</B> and should be located in your path. (Type <CODE>which +blink</CODE> to see if the program is available.) If you do not have +<B>blink</B>, you may obtain it from the Xbox-Linux project site at +<A HREF="http://xbox-linux.sf.net/">http://xbox-linux.sf.net/</A>. The +program you need is part of the <CODE>eds_i2c_staff</CODE> module in CVS. Note +the spelling.</P> +<P>Once you have installed <B>blink</B> you will need to set permissions. +<B>blink</B> needs write permission to the i2c device to function +properly. There are three methods to accomplish this. First, you could run +<CODE>mythfrontend</CODE> as root, which is the simplest method, but could +potentially be a security risk. Next, you may make the <B>blink</B> +binary setuid root, which allows non-privileged users to run a program with +root capability. This is done by typing the command: +<BLOCKQUOTE><CODE> +<PRE> +$ su +# chmod u+s /path/to/blink +</PRE> +</CODE></BLOCKQUOTE> + +The final technique would be to set the <CODE>/dev/i2c/0</CODE> device read/write +for all users, but this is the least preferred method.</P> +<P>Now it's time to setup MythTV for Xbox hardware. Enter Setup -> General. +On the second page check the 'Enable Xbox Hardware' option. Upon reentering +the settings, you should have a new option named 'Xbox'. Within this option +you may select the distribution, LED colors for recording and the update +interval. If you select GentooX as the distribution <B>led</B> will be +used as the <B>blink</B> binary name, otherwise, <B>blink</B> is used. +Colors should be self explanatory. The update interval determines how often +the frontend should poll the backend to determine if the status has changed.</P> + +<HR> +<A HREF="mythtv-HOWTO-11.html">Next</A> +<A HREF="mythtv-HOWTO-9.html">Previous</A> +<A HREF="mythtv-HOWTO.html#toc10">Contents</A> +</BODY> +</HTML> |