2.3.1 Video output devices

2.3.1.1 Setting up MTRR

It is VERY recommended to check if the MTRR registers are set up properly, because they can give a big performance boost.

Do a 'cat /proc/mtrr':

--($:~)-- cat /proc/mtrr
reg00: base=0xe4000000 (3648MB), size= 16MB: write-combining, count=9
reg01: base=0xd8000000 (3456MB), size= 128MB: write-combining, count=1

It's right, shows my Matrox G400 with 16MB memory. I did this from XFree 4.x.x , which sets up MTRR registers automatically.

If nothing worked, you have to do it manually. First, you have to find the base address. You have 3 ways to find it:

Then let's find the memory size. This is very easy, just convert video ram size to hexadecimal, or use this table:

  1 MB0x100000
2 MB0x200000
4 MB0x400000
8 MB0x800000
16 MB0x1000000
32 MB0x2000000

You know base address and memory size, let's setup MTRR registers! For example, for the Matrox card above (base=0xd8000000) with 32MB ram (size=0x2000000) just execute:

  echo "base=0xd8000000 size=0x2000000 type=write-combining" >| /proc/mtrr

Not all CPUs support MTRRs. For example older K6-2's [around 266MHz, stepping 0] doesn't support MTRR, but stepping 12's do ('cat /proc/cpuinfo' to check it').

2.3.1.2 Xv

Under XFree86 4.0.2 or newer, you can use your card's hardware YUV routines using the XVideo extension. This is what the option '-vo xv' uses. Also, this is driver supports adjusting brightness/contrast/hue/etc (unless you use the old, slow DirectShow DivX codec, which supports it everywhere), see the man page.

In order to make this work, be sure to check the following:

2.3.1.2.1 3dfx cards

Older 3dfx drivers were known to have problems with XVideo acceleration, it didn't support either YUY2 or YV12, and so. Verify that you have XFree86 version 4.2.0 or greater, it works OK with YV12 and YUY2. Previous versions, including 4.1.0, crash with YV12. If you experience strange effects using -vo xv, try SDL (it has XVideo too) and see if it helps. Check the SDL section for details.

OR, try the NEW -vo tdfxfb driver! See the tdfxfb section.

2.3.1.2.2 S3 cards

S3 Savage3D's should work fine, but for Savage4, use XFree86 version 4.0.3 or greater (in case of image problems, try 16bpp). As for S3 Virge.. there is xv support, but the card itself is very slow, so you better sell it.

NOTE: Savage cards have a slow YV12 image displaying capability (it needs to do YV12 to YUY2 conversion, because the Savage hardware can't display YV12). So when this documentation says at some point "this has YV12 output use this, it's faster", it's not sure. Try this driver, it uses MMX2 for this task and is faster than the native X driver.

2.3.1.2.3 nVidia cards

nVidia isn't a very good choice under Linux (according to nVidia, this is not true).. You'll have to use the binary closed-source nVidia driver, available at nVidia's web site. The standard XFree86 driver doesn't support XVideo for these cards, due to nVidia's closed sources/specifications.

As far as I know the latest XFree86 driver contains XVideo support for GeForce 2 and 3.

Riva128 cards don't have XVideo support even with the nVidia driver :( Complain to nVidia.

2.3.1.2.4 ATI cards
2.3.1.2.5 NeoMagic cards

These cards can be found in many laptops. Unfortunately, the driver in X 4.2.0 can't do Xv, but we have a modified, Xv-capable driver for you. Download from here. Driver provided by Stefan Seyfried.

To allow playback of DVD sized content change your XF86Config like this:

Section "Device"
    [...]
    Driver "neomagic"
    Option "OverlayMem" "829440"
    [...]
EndSection

2.3.1.2.6 Trident cards

If you want to use xv with a trident card, provided that it doesn't work with 4.1.0, try the latest CVS of XFree or wait for XFree 4.2.0. The latest CVS adds support for fullscreen xv support with the Cyberblade XP card.

2.3.1.3 DGA

2.3.1.3.1 Summary

This document tries to explain in some words what DGA is in general and what the DGA video output driver for MPlayer can do (and what it can't).

2.3.1.3.2 What is DGA

DGA is short for Direct Graphics Access and is a means for a program to bypass the X-Server and directly modifying the framebuffer memory. Technically spoken this happens by mapping the framebuffer memory into the memory range of your process. This is allowed by the kernel only if you have superuser privileges. You can get these either by logging in as root or by setting the SUID bit on the MPlayer executable (not recommended).

There are two versions of DGA: DGA1 is used by XFree 3.x.x and DGA2 was introduced with XFree 4.0.1.

DGA1 provides only direct framebuffer access as described above. For switching the resolution of the video signal you have to rely on the XVidMode extension.

DGA2 incorporates the features of XVidMode extension and also allows switching the depth of the display. So you may, although basically running a 32 bit depth X server, switch to a depth of 15 bits and vice versa.

However DGA has some drawbacks. It seems it is somewhat dependent on the graphics chip you use and on the implementation of the X server's video driver that controls this chip. So it does not work on every system ...

2.3.1.3.3 Installing DGA support for MPlayer

First make sure X loads the DGA extension, see in /var/log/XFree86.0.log:

    (II) Loading extension XFree86-DGA

See, XFree86 4.0.x or greater is VERY RECOMMENDED! MPlayer's DGA driver is autodetected on ./configure, or you can force it with --enable-dga.

If the driver couldn't switch to a smaller resolution, experiment with switches -vm (only with X 3.3.x), -fs, -bpp, -zoom to find a video mode that the movie fits in. There is no converter right now :(

Become root. DGA needs root access to be able to write directly to video memory. If you want to run it as user, then install MPlayer SUID root:

    chown root /usr/local/bin/mplayer
    chmod 750 /usr/local/bin/mplayer
    chmod +s /usr/local/bin/mplayer

Now it works as a simple user, too.

Warning: security risk
This is a big security risk! Never do this on a server or on a computer that can be accessed by other people because they can gain root privileges through SUID root MPlayer.

Now use the -vo dga option, and there you go (hope so :))! You should also try if the -vo sdl:dga option works for you. It's much faster.

2.3.1.3.4 Resolution switching

The DGA driver allows for switching the resolution of the output signal. This avoids the need for doing (slow) software scaling and at the same time provides a fullscreen image. Ideally it would switch to the exact resolution (except for honoring aspect ratio) of the video data, but the X server only allows switching to resolutions predefined in /etc/X11/XF86Config (/etc/X11/XF86Config-4 for XFree 4.0.X respectively). Those are defined by so-called modelines and depend on the capabilities of your video hardware. The X server scans this config file on startup and disables the modelines not suitable for your hardware. You can find out which modes survive with the X11 log file. It can be found at: /var/log/XFree86.0.log.

See appendix A for some sample modeline definitions.

2.3.1.3.5 DGA & MPlayer

DGA is used in two places with MPlayer: The SDL driver can be made to make use of it (-vo sdl:dga) and within the DGA driver (-vo dga). The above said is true for both; in the following sections I'll explain how the DGA driver for MPlayer works.

2.3.1.3.6 Features of the DGA driver

The DGA driver is invoked by specifying -vo dga at the command line. The default behavior is to switch to a resolution matching the original resolution of the video as close as possible. It deliberately ignores the -vm and -fs switches (enabling of video mode switching and fullscreen) - it always tries to cover as much area of your screen as possible by switching the video mode, thus refraining to use a single additional cycle of your CPU to scale the image. If you don't like the mode it chooses you may force it to choose the mode matching closest the resolution you specify by -x and -y. By providing the -v option, the DGA driver will print, among a lot of other things, a list of all resolutions supported by your current XF86-Config file. Having DGA2 you may also force it to use a certain depth by using the -bpp option. Valid depths are 15, 16, 24 and 32. It depends on your hardware whether these depths are natively supported or if a (possibly slow) conversion has to be done.

If you should be lucky enough to have enough offscreen memory left to put a whole image there, the DGA driver will use doublebuffering, which results in much smoother movie replaying. It will tell you whether double- buffering is enabled or not.

Doublebuffering means that the next frame of your video is being drawn in some offscreen memory while the current frame is being displayed. When the next frame is ready, the graphics chip is just told the location in memory of the new frame and simply fetches the data to be displayed from there. In the meantime the other buffer in memory will be filled again with new video data.

Doublebuffering may be switched on by using the option -double and may be disabled with -nodouble. Current default option is to disable doublebuffering. When using the DGA driver, onscreen display (OSD) only works with doublebuffering enabled. However, enabling doublebuffering may result in a big speed penalty (on my K6-II+ 525 it used an additional 20% of CPU time!) depending on the implementation of DGA for your hardware.

2.3.1.3.7 Speed issues

Generally spoken, DGA framebuffer access should be at least as fast as using the X11 driver with the additional benefit of getting a fullscreen image. The percentage speed values printed by MPlayer have to be interpreted with some care, as for example, with the X11 driver they do not include the time used by the X-Server needed for the actual drawing. Hook a terminal to a serial line of your box and start top to see what is really going on in your box...

Generally spoken, the speedup done by using DGA against 'normal' use of X11 highly depends on your graphics card and how well the X-Server module for it is optimized.

If you have a slow system, better use 15 or 16bit depth since they require only half the memory bandwidth of a 32 bit display.

Using a depth of 24bit is even a good idea if your card natively just supports 32 bit depth since it transfers 25% less data compared to the 32/32 mode.

I've seen some AVI files already be replayed on a Pentium MMX 266. AMD K6-2 CPUs might work at 400 MHZ and above.

2.3.1.3.8 Known bugs

Well, according to some developers of XFree, DGA is quite a beast. They tell you better not to use it. Its implementation is not always flawless with every chipset driver for XFree out there.

2.3.1.3.9 Future work
2.3.1.3.A Some modelines
  Section "Modes"
    Identifier    "Modes[0]"
    Modeline	"800x600"  40     800 840 968 1056  600 601 605 628
    Modeline	"712x600"  35.0   712 740 850 900   400 410 412 425
    Modeline	"640x480"  25.175 640 664 760 800   480 491 493 525
    Modeline 	"400x300"  20     400 416 480 528   300 301 303 314 Doublescan
    Modeline	"352x288"  25.10  352 368 416 432   288 296 290 310
    Modeline	"352x240"  15.750 352 368 416 432   240 244 246 262 Doublescan
    Modeline	"320x240"  12.588 320 336 384 400   240 245 246 262 Doublescan
  EndSection

These entries work fine with my Riva128 chip, using nv.o X server driver module.

2.3.1.3.B Bug Reports

If you experience troubles with the DGA driver please feel free to file a bug report to me (e-mail address below). Please start MPlayer with the -v option and include all lines in the bug report that start with vo_dga:

Please do also include the version of X11 you are using, the graphics card and your CPU type. The X11 driver module (defined in XF86-Config) might also help. Thanks!

Acki (acki@acki-netz.de, www.acki-netz.de)

2.3.1.4 SDL

SDL (Simple Directmedia Layer) is basically a unified video/audio interface. Programs that use it know only about SDL, and not about what video or audio driver does SDL actually use. For example a Doom port using SDL can run on svgalib, aalib, X, fbdev, and others, you only have to specify the (for example) video driver to use with the SDL_VIDEODRIVER environment variable. Well, in theory.

With MPlayer, we used its X11 driver's software scaler ability for cards/drivers that doesn't support XVideo, until we made our own (faster, nicer) software scaler. Also we used its aalib output, but now we have ours which is more comfortable. Its DGA mode was better than ours, until recently. Get it now? :)

It also helps with some buggy drivers/cards if the video is jerky (not slow system problem), or audio is lagging.

SDL video output supports displaying subtitles under the movie, on the (if present) black bar.

There are several command line switches for SDL:

-vo sdl:name
specifies sdl video driver to use (i.e.. aalib, dga, x11)
-ao sdl:name
specifies sdl audio driver to use (i.e. dsp, esd, arts)
-noxv
disables XVideo hardware acceleration
-forcexv
tries to force XVideo acceleration

SDL Keys:

Ftoggles fullscreen/windowed mode
Ccycles available fullscreen modes
W/Smappings for * and / (mixer control)

Known bugs:

2.3.1.5 SVGAlib

Installation

You'll have to install svgalib and its development package in order for MPlayer build its SVGAlib driver (autodetected, but can be forced), and don't forget to edit /etc/vga/libvga.config to suit your card & monitor.

Notes

Be sure not to use the -fs switch, since it toggles the usage of the software scaler, and it's slow. If you really need it, use the -sws 4 option which will produce bad quality, but is somewhat faster.

EGA (4bpp) support

SVGAlib incorporates EGAlib, and MPlayer has the possibility to display any movie in 16 colors, thus usable in the following sets:

The bpp (bits per pixel) value must be set to 4 by hand:
  -bpp 4
The movie probably must be scaled down to fit in EGA mode:
  -vop scale=640:350 or
  -vop scale=320:200
For that we need fast but bad quality scaling routine:
  -sws 4
Maybe automatic aspect correction has to be shut off:
  -noaspect

2.3.1.6 Framebuffer output (FBdev)

Whether to build the FBdev target is autodetected during ./configure . Read the framebuffer documentation in the kernel sources (Documentation/fb/*) for more information.

If your card doesn't support VBE 2.0 standard (older ISA/PCI cards, such as S3 Trio64), only VBE 1.2 (or older?): Well, VESAfb is still available, but you'll have to load SciTech Display Doctor (formerly UniVBE) before booting Linux. Use a DOS boot disk or whatever. And don't forget to register your UniVBE ;))

The FBdev output takes some additional parameters above the others:

-fb
specify the framebuffer device to use (/dev/fb0)
-fbmode
mode name to use (according to /etc/fb.modes)
-fbmodeconfig
config file of modes (default /etc/fb.modes)
-monitor_hfreq
-monitor_vfreq
-monitor_dotclock
Important values, see example.conf

If you want to change to a specific mode, then use

    mplayer -vm -fbmode (NameOfMode) filename

NOTE: FBdev video mode changing _does not work_ with the VESA framebuffer, and don't ask for it, since it's not an MPlayer limitation.

2.3.1.7 Matrox framebuffer (mga_vid)

This section is about the Matrox G200/G400/G450/G550 BES (Back-End Scaler) support, the mga_vid kernel driver. It's active developed by me (A'rpi), and it has hardware VSYNC support with triple buffering. It works on both framebuffer console and under X.

WARNING: on non-Linux systems, use VIDIX for mga_vid!

Installation:

  1. To use it, you first have to compile mga_vid.o:

    cd drivers
    make

  2. Then create the /dev/mga_vid device:

    mknod /dev/mga_vid c 178 0

    and load the driver with

    insmod mga_vid.o

  3. You should verify the memory size detection using the dmesg command. If it's bad, use the mga_ram_size option (rmmod mga_vid first), specify card's memory size in MB:

    insmod mga_vid.o mga_ram_size=16

  4. To make it load/unload automatically when needed, first insert the following line at the end of /etc/modules.conf:

    alias char-major-178 mga_vid

    Then copy the mga_vid.o module to the appropriate place under /lib/modules/<kernel version>/somewhere.

    Then run

    depmod -a

  5. Now you have to (re)compile MPlayer, configure will detect /dev/mga_vid and build the 'mga' driver. Using it from MPlayer goes by -vo mga if you have matroxfb console, or -vo xmga under XFree86 3.x.x or 4.x.x.

The mga_vid driver cooperates with Xv.

The /dev/mga_vid device file can be read (for example by cat /dev/mga_vid) for some info, and written for brightness change: echo "brightness=120" > /dev/mga_vid

2.3.1.8 3dfx YUV support (tdfxfb)

This driver uses the kernel's tdfx framebuffer driver to play movies with YUV acceleration. You'll need a kernel with tdfxfb support, and recompile with ./configure --enable-tdfxfb

2.3.1.9 OpenGL output

MPlayer supports displaying movies using OpenGL, but if your platform/driver supports xv as should be the case on a PC with Linux, use xv instead, OpenGL performance is considerably worse. If you have an X11 implementation without xv support, OpenGL is a viable alternative.

Unfortunately not all drivers support this feature. The Utah-GLX drivers (for XFree86 3.3.6) support it for all cards. See http://utah-glx.sourceforge.net for details about how to install it.

XFree86(DRI) 4.0.3 or later supports OpenGL with Matrox and Radeon cards, 4.2.0 or later supports Rage128. See http://dri.sourceforge.net for download and installation instructions.

2.3.1.10 AAlib - text mode displaying

AAlib is a library for displaying graphics in text mode, using powerful ASCII renderer. There are LOTS of programs already supporting it, like Doom, Quake, etc. MPlayer contains a very usable driver for it. If ./configure detects aalib installed, the aalib libvo driver will be built.

You can use some keys in the AA Window to change rendering options:

  1  decrease contrast
2increase contrast
3decrease brightness
4increase brightness
5switch fast rendering on/off
6set dithering mode (none, error distribution, Floyd Steinberg)
7invert image
atoggles between aa and MPlayer control)

The following command line options can be used:

-aaosdcolor=V
change OSD color
-aasubcolor=V
change subtitle color

where V can be: (0/normal, 1/dark, 2/bold, 3/bold font, 4/reverse, 5/special)

AAlib itself provides a large sum of options. Here are some important:

-aadriver
set recommended aa driver (X11, curses, Linux)
-aaextended
use all 256 characters
-aaeight
use eight bit ASCII
-aahelp
prints out all aalib options

NOTE: the rendering is very CPU intensive, especially when using AA-on-X (using aalib on X), and it's least CPU intensive on standard, non-framebuffer console. Use SVGATextMode to set up a big textmode, then enjoy! (secondary head Hercules cards rock :)) (anyone can enhance fbdev to do conversion/dithering to hgafb? Would be neat :)

Use the -framedrop option if your computer isn't fast enough to render all frames!

Playing on terminal you'll get better speed and quality using the Linux driver, not curses (-aadriver linux). But therefore you need write access on /dev/vcsa<terminal>. That isn't autodetected by aalib, but vo_aa tries to find the best mode. See http://aa-project.sourceforge.net/tune/ for further tuning issues.

2.3.1.11 VESA - output to VESA BIOS

This driver was designed and introduced as a generic driver for any video card which has VESA VBE 2.0 compatible BIOS. Another advantage of this driver is that it tries to force TV output on.
VESA BIOS EXTENSION (VBE) Version 3.0 Date: September 16, 1998 (Page 70) says:

Dual-Controller Designs
VBE 3.0 supports the dual-controller design by assuming that since both controllers are typically provided by the same OEM, under control of a single BIOS ROM on the same graphics card, it is possible to hide the fact that two controllers are indeed present from the application. This has the limitation of preventing simultaneous use of the independent controllers, but allows applications released before VBE 3.0 to operate normally. The VBE Function 00h (Return Controller Information) returns the combined information of both controllers, including the combined list of available modes. When the application selects a mode, the appropriate controller is activated. Each of the remaining VBE functions then operates on the active controller.

So you have chances to get working TV-out by using this driver.
(I guess that TV-out frequently is standalone head or standalone output at least.)

Advantages:

Disadvantages:

Don't use this driver with GCC 2.96! It won't work!

Command line options available for VESA:

-vo vesa:opts
currently recognized: dga to force dga mode and nodga to disable dga mode. Note: you may omit these parameters to enable autodetect of dga mode. (In the future also will specify mode parameters such as refresh rate, interlacing, doublescan and so on. Samples: i43, 85, d100)
-screenw, -screenh, -bpp
force userdefined mode
-x, -y
set userdefined prescaling
-zoom
enables userdefined prescaling
-fs
scales image to fullscreen
-fs -zoom
scales userdefined prescaling to fullscreen
-double
enables double buffering mode. (Available only in DGA mode). Should be slower of single buffering, but has no flickering effects.

Known problems and workaround:

2.3.1.12 X11

Avoid if possible. Outputs to X11 (uses shared memory extension), with no hardware acceleration at all. Supports (MMX/3DNow/SSE accelerated, but still slow) software scaling, use the options -fs -zoom. Most cards have hardware scaling support, use the -vo xv output for them, or -vo xmga for Matroxes.

The problem is that most cards' driver doesn't support hardware acceleration on the second head/TV. In those cases, you see green/blue colored window instead of the movie. This is where this driver comes in handy, but you need powerful CPU to use software scaling. Don't use the SDL driver's software output+scaler, it has worse image quality!

Software scaling is very slow, you better try changing video modes instead. It's very simple. See the DGA section's modelines, and insert them into your XF86Config.

If you can't find the modes you inserted, browse XFree86's output. Some drivers can't use low pixelclocks that are needed for low resolution video modes.

2.3.1.13 VIDIX

VIDIX is the abbreviation for VIDeo Interface for *niX.
VIDIX was designed and introduced as an interface for fast user-space drivers providing such video performance as mga_vid does for Matrox cards. It's also very portable.

This interface was designed as an attempt to fit existing video acceleration interfaces (known as mga_vid, rage128_vid, radeon_vid, pm3_vid) into a fixed scheme. It provides highlevel interface to chips which are known as BES (BackEnd scalers) or OV (Video Overlays). It doesn't provide lowlevel interface to things which are known as graphics servers. (I don't want to compete with X11 team in graphics mode switching). I.e. main goal of this interface is to maximize the speed of video playback.

USAGE

Indeed it doesn't matter which video output driver is used with VIDIX.

REQUIREMENTS

I hope that probably every video output driver of MPlayer will recognize :vidix subdevice.

USAGE METHODS

When VIDIX is used as subdevice (-vo vesa:vidix) then video mode configuration is performed by video output device (vo_server in short). Therefore you can pass into command line of MPlayer the same keys as for vo_server. In addition it understands -double key as globally visible parameter. (I recommend using this key with VIDIX at least for ATI's card).
As for -vo xvidix: currently it recognizes the following options: -fs -zoom -x -y -double.

Also you can specify VIDIX's driver directly as third subargument in command line:

  mplayer -vo xvidix:mga_vid.so -fs -zoom -double file.avi
or
  mplayer -vo vesa:vidix:radeon_vid.so -fs -zoom -double -bpp 32 file.avi

But it's dangerous, and you shouldn't do that. In this case given driver will be forced and result is unpredictable (it may freeze your computer). You should do that ONLY if you are absolutely sure it will work, and MPlayer doesn't do it automatically. Please tell about it to the developers. The Right Way is to use VIDIX without arguments to enable driver autodetection.

VIDIX is very new technology and it's extremely possible that on your system (OS=abc CPU=xyz) it won't work. In this case only solution for you it's port it (mainly libdha). But there is hope that it will work on those systems where X11 does.

Warning: security risk
Unfortunately you must have root privileges to use VIDIX due to direct hardware access. At least the SUID bit on the MPlayer executable must be set.

VIDEO EQUALIZER

This is a video equalizer implemented especially for VIDIX. You can use it either with 1-8 keys as described in the man page, or by command line arguments. MPlayer recognizes the following options:

-brightness
Adjust BRIGHTNESS of video output. It's not equal to brightness adjusting on monitor panel or on TV. It changes intensity of RGB components of video signal from black to white screen.
-contrast
Adjust CONTRAST of video output. Works in similar manner as brightness.
-saturation
Adjust SATURATION of video output. You can get grayscale output with this option.
-hue
Adjust HUE of video signal. You can get colored negative of image with this option.
-red_intensity
Adjust intensity of RED component of video signal.
-green_intensity
Adjust intensity of GREEN component of video signal.
-blue_intensity
Adjust intensity of BLUE component of video signal.

Each parameter can accept values from -1000 to +1000.
Default value for each parameter is 0.

Note: Not every driver provides support for each of those parameters. Currently only radeon_vid.so provides full support for video equalizing. Other drivers only partly support these options.

Examples:
mplayer -vo vesa:vidix -brightness -300 -contrast 200 filename.avi
or
mplayer -vo xvidix -red_intensity -50 -saturation 400 -hue 300 filename.vob

2.3.1.14 Zr

This is a display-driver (-vo zr) for a number of MJPEG capture/playback cards (tested for DC10+ and Buz, and it should work for the LML33 and the original DC10). The driver works by encoding the frame to jpeg and then sending it to the card. For the jpeg encoding libavcodec is used, and required. With the special cinerama mode, you can watch movies in true wide screen provided that you have two beamers and two MJPEG cards. Depending on resolution and quality settings, this driver may require a lot of CPU power, remember to specify -framedrop if your machine is too slow. Note: My AMD K6-2 350MHz is (with -framedrop) quite adequate for watching VCD sized material and downscaled movies.

This driver talks to the kernel driver available at http://mjpeg.sourceforge.net, so you must get it working first. The presence of an MJPEG card is autodetected by the configure script, if autodetection fails, force detection with

  ./configure --enable-zr

The output can be controlled by several options, a long description of the options can be found in the man page, a short list of options can be viewed by running

  mplayer -zrhelp

Things like scaling and the OSD (on screen display) are not handled by this driver but can be done using the video filters. For example, suppose that you have a movie with a resolution of 512x272 and you want to view it fullscreen on your DC10+. There are three main possibilities, you may scale the movie to a width of 768, 384 or 192. For performance and quality reasons, I would choose to scale the movie to 384x204 using the fast bilinear software scaler. The commandline is

  mplayer -vo zr -sws 0 -vop scale=384:204 movie.avi

Cropping can be done by the crop filter and by this driver itself. Suppose that a movie is too wide for display on your Buz and that you want to use -zrcrop to make the movie less wide, the you would issue the following command

  mplayer -vo zr -zrcrop 720x320+80+0 benhur.avi
if you want to use the crop filter, you would do
  mplayer -vo zr -vop crop=720:320:80:0 benhur.avi

Extra occurances of -zrcrop invoke cinerama mode, i.e. you can distribute the movie over several TV's or beamers to create a larger screen. Suppose you have two beamers. The left one is connected to your Buz at /dev/video1 and the right one is connected to your DC10+ at /dev/video0. The movie has a resolution of 704x288. Suppose also that you want the right beamer in black and white and that the right beamer should have jpeg frames at quality 10, then you would issue the following command

  mplayer -vo zr -zrdev /dev/video0 -zrcrop 352x288+352+0 -zrxdoff 0 -zrbw \
          -zrcrop 352x288+0+0 -zrdev /dev/video1 -zrquality 10 movie.avi

You see that the options appearing before the second -zrcrop only apply to the DC10+ and that the options after the second -zrcrop apply to the Buz. The maximum number of MJPEG cards participating in cinerama is four, so you can buid a 2x2 vidiwall.

Finally an important remark: Do not start or stop XawTV on the playback device during playback, it will crash your computer. It is, however, fine to FIRST start XawTV, THEN start MPlayer, wait for MPlayer to finish and THEN stop XawTV.

2.3.1.15 DVB

MPlayer supports cards with the Siemens DVB chipset from vendors like Siemens, Technotrend, Galaxis or Hauppauge. The latest DVB drivers are available from the Linux TV site. If you want to do software transcoding you should have at least a 1GHz CPU.

Configure should detect your DVB card. If it did not, force detection with

  ./configure --enable-dvb

If you have ost headers at a non-standard path, set the path with

  ./configure --with-extraincdir=<DVB source directory>/ost/include

Then compile and install as usual.

USAGE

Hardware decoding (playing standard MPEG1/2 files) can be done with this command:

  mplayer -ao mpegpes -vo mpegpes file.mpg|vob

Software decoding or transcoding different formats to MPEG1 can be achieved using a command like this:

  mplayer -ao mpegpes -vo mpegpes -vop lavc yourfile.ext
  mplayer -ao mpegpes -vo mpegpes -vop fame,expand yourfile.ext

Note that DVB cards only support heights 288 and 576 for PAL or 240 and 480 for NTSC. You must rescale for other heights by adding scale=width:height with the width and height you want to the -vop option. DVB cards accept various widths, like 720, 704, 640, 512, 480, 352 etc and do hardware scaling in horizontal direction, so you do not need to scale horizontally in most cases. For a 512x384 (aspect 4:3) DivX try:

  mplayer -ao mpegpes -vo mpegpes -vop lavc,scale=512:576

If you have a widescreen movie and you do not want to scale it to full height, you can use the expand=w:h plugin to add black bands. To view a 640x384 DivX, try:

  mplayer -ao mpegpes -vo mpegpes -vop lavc,expand=640:576 file.avi

If your CPU is too slow for a full size 720x576 DivX, try downscaling:

  mplayer -ao mpegpes -vo mpegpes -vop lavc,scale=352:576 file.avi

If speed does not improve, try vertical downscaling, too:

  mplayer -ao mpegpes -vo mpegpes -vop lavc,scale=352:288 file.avi

For OSD and subtitles use the expand feature of the OSD plugin. So, instead of expand=w:h or expand=w:h:x:y, use expand=w:h:x:y:1 (the 5th parameter :1 at the end will enable OSD rendering). You may want to move the image up a bit to get a bigger black zone for subtitles. You may also want to move subtitles up, if they are outside your TV screen, use the -subpos <0-100> switch to adjust this (-subpos 80 is a good choice).

In order to play non-25fps movies on a PAL TV or with a slow CPU, add the -framedrop option.

To keep the aspect ratio of DivX files and get the optimal scaling parameters (hardware horizontal scaling and software vertical scaling while keeping the right aspect ratio), use the new dvbscale plugin:

for  3:4 TV:  -vop lavc,expand=-1:576:-1:-1:1,scale=-1:0,dvbscale
for 16:9 TV:  -vop lavc,expand=-1:576:-1:-1:1,scale=-1:0,dvbscale=1024

FUTURE

If you have questions or want to hear feature announcements and take part in discussions on this subject, join our MPlayer-DVB mailing list. Please remember that the list language is English.

In the future you may expect the ability to display OSD and subtitles using the native OSD feature of DVB cards, as well as more fluent playback of non-25fps movies and realtime transcoding between MPEG2 and MPEG4 (partial decompression).

2.3.1.16 DXR3/Hollywood+

MPlayer supports hardware accelerated playback with the Creative DXR3 and Sigma Designs Hollywood Plus cards. These cards both use the em8300 MPEG decoder chip from Sigma Designs.

First of all you will need properly installed DXR3/H+ drivers, version 0.12.0 or later. You can find the drivers and installation instructions at the DXR3 & Hollywood Plus for Linux site. Configure should detect your card automatically, compilation should go without problems.

Usage:

-vo dxr3:noprebuf:<device>
noprebuf turns off prebuffering. Prebuffering is a feature of the em8300 chip that enables it to hold more than one frame of video at a time. This means that when you are running with prebuffering (default) MPlayer will try to keep the video buffer filled with data at all times. If you are on a slow machine MPlayer will probably use close to, or precisely 100% of CPU. This is especially common if you play pure MPEG streams (like DVDs, SVCDs a.s.o.) since MPlayer will not have to reencode it to MPEG it will fill the buffer very fast.
With prebuffering video playback is much less sensitive to other programs hogging the CPU, it will not drop frames unless applications hog the CPU for a long time.
Prebuffering does not work on all machines (especially Athlons where it is turned off automatically). If you experience problems with video/audio sync use noprebuf. When running without prebuffering the em8300 is much more sensitive to CPU load, so it is highly suggested that you turn on MPlayer's -framedrop option to avoid further loss of sync.
<device> = device number to use if you have more than one em8300 card.
Any of these options may be left out, but they must be specified in this exact order, i.e. dxr3:noprebuf works, dxr3:1 works, but dxr3:1:noprebuf will not.
-ao oss:/dev/em8300_ma-X
For audio output, where X is the device number (0 if one card).
-aop list=resample:fout=xxxxx
The em8300 cannot play back samplerates lower than 44100Hz. If the sample rate is below 44100Hz select either 44100Hz or 48000Hz depending on which one matches closest. I.e. if the movie uses 22050Hz use 44100Hz as 44100 / 2 = 22050, if it is 24000Hz use 48000Hz as 48000 / 2 = 24000 and so on. This does not work with digital audio output (-ac hwac3).
-vop lavc/fame
To watch non-MPEG content on the em8300 (i.e. DivX or RealVideo) you have to specify an MPEG1 video filter such as libavcodec (lavc) or libfame (fame). At the moment lavc is both faster and gives better image quality, it is suggested that you use that unless you have problems with it. See the man page for further info about -vop lavc/fame.
-ac hwac3
The em8300 supports playing back AC3 audio (surround sound) through the digital audio output of the card. Read hardware AC3 section for further information on AC3.

Overlay

To get overlay run dxr3view that comes with the em8300 package before starting MPlayer. You can set various options in dxr3view by pressing T while holding the mouse cursor above the window.

MPEG1, MPEG2, VCD and DVD Notes

MPEG1/2 content should now automatically be detected by MPlayer and it will use the hardware acceleration of the DXR3 to play it. If not, you can force it to hardware acceleration with -vc mpegpes. Also, if you plan to use postprocessing filters you must use -vc mpeg12.

In some instances, subtitles may not appear properly in sync with the A/V stream when using hardware decoding (-vc mpegpes). This is a known bug. The em8300 will also improperly handle subtitles that are too big, and may hang for a second or two. At this time, the only workaround is to use -vc mpeg12 when viewing DVDs with subtitles. When running with -vc mpeg12 MPlayer will reencode video to MPEG (even if it already is MPEG). This means that it will need more CPU power, and you might loose some picture quality.

2.3.1.A TV-out support

2.3.1.A.1 Matrox G400 cards

Under Linux you have 2 methods to get G400 TV out working:

IMPORTANT: for Matrox G450/G550 TV-out instructions, please see the next section!

2.3.1.A.2 Matrox G450/G550 cards

TV output support for these cards has only been recently introduced, and is not yet in the mainstream kernel. Currently the mga_vid module can't be used AFAIK, because the G450/G550 driver works only in one configuration: the first CRTC chip (with much more features) on the first display (on monitor), and the second CRTC (no BES - for explanation on BES, please see the G400 section above) on TV. So you can only use MPlayer's fbdev output driver at the present.

The first CRTC can't be routed to the second head currently. The author of the kernel matroxfb driver - Petr Vandrovec - will maybe make support for this, by displaying the first CRTC's output onto both of the heads at once, as currently recommended for G400, see the section above.

The necessary kernel patch and the detailed howto is downloadable from http://www3.sympatico.ca/dan.eriksen/matrox_tvout

2.3.1.A.3 ATI cards
PREAMBLE

Currently ATI doesn't want to support any of its TV-out chips under Linux, because of their licensed Macrovision technology.

ATI CARDS TV-OUT STATUS ON LINUX

On other cards, just use the VESA driver, without VIDIX. Powerful CPU is needed, though.

Only thing you need to do - have TV connector plugged in before booting your PC since video BIOS initializes itself only once during POST procedure.

2.3.1.A.4 Voodoo 3

Check this URL.