2.3. Устройства вывода
Пред. | Глава 2. Возможности | След.

## 2.3. Устройства вывода

### 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:

1. from X11 startup messages, for example:

       (--) SVGA: PCI: Matrox MGA G400 AGP rev 4, Memory @ 0xd8000000, 0xd4000000
       (--) SVGA: Linear framebuffer at 0xD8000000

2. from `/proc/pci` (use lspci -v command):

       01:00.0 VGA compatible controller: Matrox Graphics, Inc.: Unknown device 0525
       Memory at d8000000 (32-bit, prefetchable)

3. from mga_vid kernel driver messages (use dmesg):

       mga_mem_base = d8000000

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

1 MB | 0x100000
2 MB | 0x200000
4 MB | 0x400000
8 MB | 0x800000
16 MB | 0x1000000
32 MB | 0x2000000

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 have MTRRs. For example older K6-2 (around 266MHz, stepping 0) CPUs don't have MTRRs, but stepping 12 does (execute cat /proc/cpuinfo to check it).

#### 2.3.1.2. Video outputs for traditional video cards

##### 2.3.1.2.1. 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 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:

1. You have to use XFree86 4.0.2 or newer (former versions don't have XVideo)

2. Your card actually supports hardware acceleration (modern cards do)

3. X loads the XVideo extension, it's something like this:

       (II) Loading extension XVideo

   in `/var/log/XFree86.0.log`

   ### Замечание

   This loads only the XFree86's extension. In a good install, this is always loaded, and doesn't mean that the card's XVideo support is loaded!

4. Your card has Xv support under Linux. To check, try xvinfo, it is the part of the XFree86 distribution. It should display a long text, similar to this:

       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
       (...)
           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)
       (...etc...)

   It must support YUY2 packed, and YV12 planar pixel formats to be usable with MPlayer.

5. And finally, check if MPlayer was compiled with 'xv' support. Do a mplayer -vo help | grep xv . If 'xv' support was built a line similar to this should appear:

         xv      X11/Xv

###### 2.3.1.2.1.1. 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, crashes 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.

###### 2.3.1.2.1.2. 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.

### Замечание

It's currently unclear which Savage models lack YV12 support, and convert by driver (slow). If you suspect your card, get a newer driver, or ask politely on the mplayer-users mailing list for an MMX/3DNow! enabled driver.

###### 2.3.1.2.1.3. nVidia cards

nVidia isn't always a very good choice under Linux (according to nVidia, this is not true)... XFree86's open-source driver supports most of these cards, but for some cases, you'll have to use the binary closed-source nVidia driver, available at nVidia's web site. You'll always need this driver if you want 3D acceleration, too.

Riva128 cards don't have XVideo support with XFree86's nVidia driver :( Complain to nVidia.

However, MPlayer contains a VIDIX driver for most nVidia cards. Currently it is in beta stage, and has some drawbacks. For more information, see nVidia VIDIX section.

###### 2.3.1.2.1.4. ATI cards

The GATOS driver (which you should use, unless you have Rage128 or Radeon) has VSYNC enabled by default. It means that decoding speed (!) is synced to the monitor's refresh rate. If playing seems to be slow, try disabling VSYNC somehow, or set refresh rate to a n*(fps of the movie) Hz.

Radeon VE - if you need X, use XFree86 4.2.0 or greater for this card. No TV out support. Of course with MPlayer you can happily get accelerated display, with or without TV output, and no libraries or X are needed. Read the VIDIX section.

###### 2.3.1.2.1.5. NeoMagic cards

These cards can be found in many laptops. You must use XFree86 4.3.0 or above, or else use Stefan Seyfried's Xv-capable drivers. Just choose the one that applies to your version of XFree86.

XFree86 4.3.0 includes Xv support, yet Bohdan Horst sent a small patch against the XFree86 sources that speeds up framebuffer operations (so XVideo) up to four times. The patch has been included in XFree86 CVS and should be in the next release after 4.3.0.

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

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

###### 2.3.1.2.1.6. Trident cards

If you want to use xv with a trident card, provided that it doesn't work with 4.1.0, install XFree 4.2.0. 4.2.0 adds support for fullscreen Xv support with the Cyberblade XP card.

Alternatively, MPlayer contains a VIDIX driver for the Cyberblade/i1 card.

###### 2.3.1.2.1.7. Kyro/PowerVR cards

If you want to use Xv with a Kyro based card (for example Hercules Prophet 4000XT), you should download the drivers from the PowerVR site

##### 2.3.1.2.2. DGA

PREAMBLE. 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).

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...

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 highly recommended! MPlayer's DGA driver is autodetected by `./configure`, or you can force it with `--enable-dga`.

If the driver couldn't switch to a smaller resolution, experiment with options `-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 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.

### 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 `-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!

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.X.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`.

These entries are known to work fine with a Riva128 chip, using the nv.o X server driver module.

    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

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.

FEATURES. 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` options (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 `XF86Config` 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.

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 16 bit depth since they require only half the memory bandwidth of a 32 bit display.

Using a depth of 24 bit 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.

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.

- With XFree 4.0.3 and `nv.o` there is a bug resulting in strange colors.
- ATI driver requires to switch mode back more than once after finishing using of DGA.
- Some drivers simply fail to switch back to normal resolution (use Ctrl+Alt+Keypad + and Ctrl+Alt+Keypad - to switch back manually).
- Some drivers simply display strange colors.
- Some drivers lie about the amount of memory they map into the process's address space, thus vo_dga won't use doublebuffering (SIS?).
- Some drivers seem to fail to report even a single valid mode. In this case the DGA driver will crash telling you about a nonsense mode of 100000x100000 or something like that.
- OSD only works with doublebuffering enabled (else it flickers).

##### 2.3.1.2.3. 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

Таблица 2.1. SDL only keys

Key | Action
--- | ---
c | cycles available fullscreen modes
n | changes back to normal mode

Known bugs:

- Keys pressed under sdl:aalib console driver repeat forever. (use `-vo aa`!) It's bug in SDL, I can't change it (tested with SDL 1.2.1).
- DO NOT USE SDL with GUI! It won't work as it should.

##### 2.3.1.2.4. 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 and monitor.

### Замечание

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:

- EGA card with EGA monitor: 320x200x4bpp, 640x200x4bpp, 640x350x4bpp
- EGA card with CGA monitor: 320x200x4bpp, 640x200x4bpp

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:

    -vf scale=640:350

or

    -vf 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

### Замечание

According to my experience the best image quality on EGA screens can be achieved by decreasing the brightness a bit: `-vf eq=-20:0`. I also needed to lower the audio samplerate on my box, because the sound was broken on 44kHz: `-srate 22050`.

You can turn on OSD and subtitles only with the `expand` filter, see the man page for exact parameters.

##### 2.3.1.2.5. 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 name_of_mode filename

- `-vm` alone will choose the most suitable mode from `/etc/fb.modes`. Can be used together with `-x` and `-y` options too. The `-flip` option is supported only if the movie's pixel format matches the video mode's pixel format. Pay attention to the bpp value, fbdev driver tries to use the current, or if you specify the `-bpp` option, then that.

- `-zoom` option isn't supported (use `-vf scale`). You can't use 8bpp (or less) modes.

- You possibly want to turn the cursor off:

      echo -e '\033[?25l'

  or

      setterm -cursor off

  and the screen saver:

      setterm -blank 0

  To turn the cursor back on:

      echo -e '\033[?25h'

  or

      setterm -cursor on

### Замечание

FBdev video mode changing does not work with the VESA framebuffer, and don't ask for it, since it's not an MPlayer limitation.

##### 2.3.1.2.6. 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 actively developed by A'rpi, and it has hardware VSYNC support with triple buffering. It works on both framebuffer console and under X.

### Внимание

This is Linux only! On non-Linux (tested on FreeBSD) systems, you can use VIDIX instead!

Installation:

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

       cd drivers
       make

2. Then create `/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 some info, for example by

    cat /dev/mga_vid

and can be written for brightness change:

    echo "brightness=120" > /dev/mga_vid

##### 2.3.1.2.7. 3Dfx YUV support

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

##### 2.3.1.2.8. 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.

A hint from one of our users: the GL video output can be used to get vsynced TV output. You'll have to set an environment variable (at least on nVidia):

export $__GL_SYNC_TO_VBLANK=1

##### 2.3.1.2.9. 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:

Key | Action
--- | ---
1 | decrease contrast
2 | increase contrast
3 | decrease brightness
4 | increase brightness
5 | switch fast rendering on/off
6 | set dithering mode (none, error distribution, Floyd Steinberg)
7 | invert image
8 | toggles 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

### Замечание

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 :)) (but IMHO you can use `-vf 1bpp` option to get graphics on hgafb:)

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.

##### 2.3.1.2.10. `libcaca` - Color ASCII Art library

The `libcaca` library is a graphics library that outputs text instead of pixels, so that it can work on older video cards or text terminals. It is not unlike the famous `AAlib` library. `libcaca` needs a terminal to work, thus it should work on all Unix systems (including Mac OS X) using either the `slang` library or the `ncurses` library, on DOS using the `conio.h` library, and on Windows systems using either `slang` or `ncurses` (through Cygwin emulation) or `conio.h`. If `./configure` detects `libcaca`, the caca libvo driver will be built.

The differences with `AAlib` are the following:

- 16 available colors for character output (256 color pairs)
- color image dithering

But `libcaca` also has the following limitations:

- no support for brightness, contrast, gamma

You can use some keys in the caca window to change rendering options:

Key | Action
--- | ---
d | Toggle `libcaca` dithering methods.
a | Toggle `libcaca` antialiasing.
b | Toggle `libcaca` background.

`libcaca` will also look for certain environment variables:

`CACA_DRIVER`
  Set recommended caca driver. e.g. ncurses, slang, x11.
`CACA_GEOMETRY (X11 only)`
  Specifies the number of rows and columns. e.g. 128x50.
`CACA_FONT (X11 only)`
  Specifies the font to use. e.g. fixed, nexus.

Use the `-framedrop` option if your computer is not fast enough to render all frames.

##### 2.3.1.2.11. 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

- You have chances to watch movies if Linux even doesn't know your video hardware.
- You don't need to have installed any graphics' related things on your Linux (like X11 (aka XFree86), fbdev and so on). This driver can be run from text-mode.
- You have chances to get working TV-out. (It's known at least for ATI's cards).
- This driver calls `int 10h` handler thus it's not an emulator - it calls real things of real BIOS in real-mode (actually in vm86 mode).
- You can use VIDIX with it, thus getting accelerated video display and TV output at the same time! (Recommended for ATI cards.)
- If you have VESA VBE 3.0+, and you had specified `monitor-hfreq, monitor-vfreq, monitor-dotclock` somewhere (config file, or command line) you will get the highest possible refresh rate. (Using General Timing Formula). To enable this feature you have to specify all your monitor options.

DISADVANTAGES

- It works only on x86 systems.
- It can be used only by `root`.
- Currently it's available only for Linux.

### Важно

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. In dga mode you can enable double buffering via the `-double` option. Note: you may omit these parameters to enable autodetection of dga mode.

KNOWN PROBLEMS AND WORKAROUNDS

- If you have installed NLS font on your Linux box and run VESA driver from text-mode then after terminating MPlayer you will have ROM font loaded instead of national. You can load national font again by using setsysfont utility from the Mandrake distribution for example. (Hint: The same utility is used for localization of fbdev).
- Some Linux graphics drivers don't update active BIOS mode in DOS memory. So if you have such problem - always use VESA driver only from text-mode. Otherwise text-mode (#03) will be activated anyway and you will need restart your computer.
- Often after terminating VESA driver you get black screen. To return your screen to original state - simply switch to other console (by pressing Alt+F<x>) then switch to your previous console by the same way.
- To get working TV-out you need have plugged TV-connector in before booting your PC since video BIOS initializes itself only once during POST procedure.

##### 2.3.1.2.12. 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 Matrox cards.

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 have XFree86 4.x.x: use the `-vm` option. It will change to a resolution your movie fits in. If it doesn't:
- With XFree86 3.x.x: you have to cycle through available resolutions with the Ctrl+Alt+plus and Ctrl+Alt+minus keys.

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.

##### 2.3.1.2.13. VIDIX

PREAMBLE. 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 a high level interface to chips which are known as BES (BackEnd scalers) or OV (Video Overlays). It doesn't provide low level 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

- You can use standalone video output driver: `-vo xvidix`. This driver was developed as X11's front end to VIDIX technology. It requires X server and can work only under X server. Note that, as it directly accesses the hardware and circumvents the X driver, pixmaps cached in the graphics card's memory may be corrupted. You can prevent this by limiting the amount of video memory used by X with the XF86Config option "VideoRam" in the device section. You should set this to the amount of memory installed on your card minus 4MB. If you have less than 8MB of video ram, you can use the option "XaaNoPixmapCache" in the screen section instead.
- There is a console VIDIX driver: `-vo cvidix`. This requires a working and initialized framebuffer for most cards (or else you'll just mess up the screen), and you'll have a similar effect as with `-vo mga` or `-vo fbdev`. nVidia cards however are able to output truly graphical video on a real text console. See the nvidia_vid section for more information.
- You can use VIDIX subdevice which was applied to several video output drivers, such as: `-vo vesa:vidix` (Linux only) and `-vo fbdev:vidix`.

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

REQUIREMENTS

- Video card should be in graphics mode (except nVidia cards with the `-vo cvidix` output driver).
- MPlayer's video output driver should know active video mode and be able to tell to VIDIX subdevice some video characteristics of server.

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 new technology and it's extremely possible that on your system 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.

Since VIDIX requires direct hardware access you can either run it as root or set the SUID bit on the MPlayer binary (Warning: This is a security risk!). Alternatively, you can use a special kernel module, like this:

1. Download the development version of svgalib (for example 1.9.17), OR download a version made by Alex especially for usage with MPlayer (it doesn't need the svgalib source to compile) from here.

2. Compile the module in the `svgalib_helper` directory (it can be found inside the `svgalib-1.9.17/kernel/` directory if you've downloaded the source from the svgalib site) and insmod it.

3. To create the necessary devices in the `/dev` directory, do a

       make device

   in the `svgalib_helper` dir, as root.

4. Move the `svgalib_helper` directory to `mplayer/main/libdha/svgalib_helper`.

5. Required if you download the source from the svgalib site: Remove the comment before the CFLAGS line containing "svgalib_helper" string from the `libdha/Makefile`.

6. Recompile and install libdha.

###### 2.3.1.2.13.1. ATI cards

Currently most ATI cards are supported natively, from Mach64 to the newest Radeons.

There are two compiled binaries: `radeon_vid` for Radeon and `rage128_vid` for Rage 128 cards. You may force one or let the VIDIX system autoprobe all available drivers.

###### 2.3.1.2.13.2. Matrox cards

Matrox G200, G400, G450 and G550 have been reported to work.

The driver supports video equalizers and should be nearly as fast as the Matrox framebuffer

###### 2.3.1.2.13.3. Trident cards

There is a driver available for the Trident Cyberblade/i1 chipset, which can be found on VIA Epia motherboards.

The driver was written and is maintained by Alastair M. Robinson

###### 2.3.1.2.13.4. 3DLabs cards

Although there is a driver for the 3DLabs GLINT R3 and Permedia3 chips, no one has tested it, so reports are welcome.

###### 2.3.1.2.13.5. nVidia cards

There's a relatively new nVidia driver out there, it's known to work on Riva 128, TNT and GeForce2 chipsets, also others have been reported working.

LIMITATIONS

- It's recommended to use the binary nVidia drivers for X before using this VIDIX driver, because some of the registers which need to be initialized haven't been discovered yet, so it will probably fail with the Open Source XFree86 `nv.o` driver.

- Currently only codecs capable of UYVY colorspace output can work in conjunction with this driver. Unfortunately, this excludes every single decoder from the `libavcodec` family. This leaves us with the following usable popular codecs: `cvid, divxds, xvid, divx4, wmv7, wmv8` and some others. Please note that this is only a temporal inconvenience. The usage syntax is as follows:

          mplayer -vf format=uyvy -vc divxds divx3file.avi

An unique feature of the nvidia_vid driver is its ability to display video on plain, pure, text-only console - with no framebuffer or X magic whatsoever. For this purpose, we'll have to use the `cvidix` video output, as the following example shows:

        mplayer -vf format=uyvy -vc divxds -vo cvidix example.avi

Reports awaited!

###### 2.3.1.2.13.6. SiS cards

This is very experimental code, just like nvidia_vid.

It's been tested on SiS 650/651/740 (the most common chipsets used in the SiS versions of the "Shuttle XPC" barebones boxes out there)

Reports awaited!

##### 2.3.1.2.14. DirectFB

> "DirectFB is a graphics library which was designed with embedded systems in mind. It offers maximum hardware accelerated performance at a minimum of resource usage and overhead." - quoted from http://www.directfb.org

I'll exclude DirectFB features from this section.

Though MPlayer is not supported as a "video provider" in DirectFB, this output driver will enable video playback through DirectFB. It will - of course - be accelerated, on my Matrox G400 DirectFB's speed was the same as XVideo.

Always try to use the newest version of DirectFB. You can use DirectFB options on the command line, using the `-dfbopts` option. Layer selection can be done by the subdevice method, e.g.: `-vo directfb:2` (layer -1 is default: autodetect)

##### 2.3.1.2.15. DirectFB/Matrox (dfbmga)

Please read the main DirectFB section for general information.

This video output driver will enable CRTC2 (on the second head) on Matrox G400/G450/G550 cards, displaying video independent of the first head.

Ville Syrjala's has a README and a HOWTO on his homepage that explain how to make DirectFB TV output run on Matrox cards.

### Замечание

the first DirectFB version with which we could get this working was 0.9.17 (it's buggy, needs that `surfacemanager` patch from the URL above). Anyway, porting of the CRTC2 code to mga_vid is underway.

#### 2.3.1.3. MPEG decoders

##### 2.3.1.3.1. DVB output and input

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 yourfile.ext
    mplayer -ao mpegpes -vo mpegpes -vf 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 `-vf` 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 -vf 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` filter to add black bands. To view a 640x384 DivX, try:

    mplayer -ao mpegpes -vo mpegpes -vf expand=640:576 file.avi

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

    mplayer -ao mpegpes -vo mpegpes -vf scale=352:576 file.avi

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

    mplayer -ao mpegpes -vo mpegpes -vf scale=352:288 file.avi

For OSD and subtitles use the OSD feature of the expand filter. 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>` option 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 filter:

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

Digital TV (DVB input module). You can use your DVB card for watching Digital TV.

You should have the programs scan and szap/tzap/czap installed; they are all included in the drivers package.

Verify that your drivers are working properly with a program such as dvbstream (that is the base of the DVB input module).

Now you should compile a `~/.mplayer/channels.conf` file, with the syntax accepted by szap/tzap/czap, or have scan compile it for you.

If you have more than one card type (e.g. Satellitar, Terrestrial and Cable) you can save your channels files as `~/.mplayer/channels.conf.sat`, `~/.mplayer/channels.conf.ter` and `~/.mplayer/channels.conf.cbl`, respectively, so as to implicitly hint MPlayer to use these files rather than `~/.mplayer/channels.conf`, and you only need to specify which card to use.

Make sure that you have have only Free to Air channels in your `channels.conf` file, or MPlayer will try to skip to the next visible one, but it may take long if there are many consecutive encrypted channels.

In your audio and video fields you can use an extended syntax: `...:pid[+pid]:...` (for a maximum of 6 pids each); in this case MPlayer will include in the stream all the indicated pids, plus pid 0 (that contains the PAT). You are encouraged to include in each row the PMT pid for the corresponding channel (if you know it). Other possible uses are: televideo pid, second audio track, etc.

To show the first of the channels present in your list, run

      mplayer dvb://

If you want to watch a specific channel, such as R1, run

      mplayer dvb://R1

If you have more than one card you also need to specify the number of the card where the channel is visible (e.g. 2) with the syntax:

      mplayer dvb://2@R1

To change channels press the h (next) and k (previous) keys, or use the OSD menu (requires a working OSD subsystem).

If your `~/.mplayer/menu.conf` contains a `<dvbsel>` entry, such as the one in the example file `etc/dvb-menu.conf` (that you can use to overwrite `~/.mplayer/menu.conf`), the main menu will show a sub-menu entry that will permit you to choose one of the channels present in your `channels.conf`, possibly preceded by a menu with the list of cards available if more than one is usable by MPlayer.

If you want to save a program to disk you can use

      mplayer -dumpfile r1.ts -dumpstream dvb://R1

If you want to record it in a different format (re-encoding it) instead you can run a command such as

      mencoder -o r1.avi -ovc xvid -xvidencopts bitrate=800 -oac mp3lame -lameopts cbr:br=128 -pp=ci dvb://R1

Read the man page for a list of options that you can pass to the DVB input module.

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).

##### 2.3.1.3.2. DXR2

MPlayer supports hardware accelerated playback with the Creative DXR2 card.

First of all you will need properly installed DXR2 drivers. You can find the drivers and installation instructions at the DXR2 Resource Center site.

USAGE

`-vo dxr2`

  enable TV output

`-vo dxr2:x11` or `-vo dxr2:xv`

  enable Overlay output in X11

`-dxr2 <option1:option2:...>`

  This option is used to control the DXR2 driver.

The overlay chipset used on the DXR2 is of pretty bad quality but the default settings should work for everybody. The OSD may be usable with the overlay (not on TV) by drawing it in the colorkey. With the default colorkey settings you may get variable results, usually you will see the colorkey around the characters or some other funny effect. But if you properly adjust the colorkey settings you should be able to get acceptable results.

Please see the man page for available options.

##### 2.3.1.3.3. 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:prebuf:sync:norm=x:`device``

  `overlay` activates the overlay instead of TVOut. It requires that you have a properly configured overlay setup to work right. The easiest way to configure the overlay is to first run autocal. Then run mplayer with dxr3 output and without overlay turned on, run dxr3view. In dxr3view you can tweak the overlay settings and see the effects in realtime, perhaps this feature will be supported by the MPlayer GUI in the future. When overlay is properly set up you will no longer need to use dxr3view. `prebuf` turns on 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 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. 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. `sync` will turn on the new sync-engine. This is currently an experimental feature. With the sync feature turned on the em8300's internal clock will be monitored at all times, if it starts to deviate from MPlayer's clock it will be reset causing the em8300 to drop any frames that are lagging behind. `norm=x` will set the TV norm of the DXR3 card without the need for external tools like em8300setup. Valid norms are 5 = NTSC, 4 = PAL-60, 3 = PAL. Special norms are 2 (auto-adjust using PAL/PAL-60) and 1 (auto-adjust using PAL/NTSC) because they decide which norm to use by looking at the frame rate of the movie. norm = 0 (default) does not change the current norm. ``device`` = device number to use if you have more than one em8300 card. Any of these options may be left out. `:prebuf:sync` seems to work great when playing DivX movies. People have reported problems using the prebuf option when playing MPEG1/2 files. You might want to try running without any options first, if you have sync problems, or DVD subtitle problems, give `:sync` a try.

`-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`).

`-vf 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 `-vf lavc/fame`. Using lavc is highly recommended. Currently there is no way of setting the fps of the em8300 which means that it is fixed to 29.97fps. Because of this it is highly recommended that you use `-vf lavc=`quality`:25` especially if you are using prebuffering. Then why 25 and not 29.97? Well, the thing is that when you use 29.97 the picture becomes a bit jumpy. The reason for this is unknown to us. If you set it to somewhere between 25 and 27 the picture becomes stable. For now all we can do is accept this for a fact.

`-vf expand=-1:-1:-1:-1:1`

  Although the DXR3 driver can put some OSD onto the MPEG1/2/4 video, it has much lower quality than MPlayer's traditional OSD, and has several refresh problems as well. The command line above will firstly convert the input video to MPEG4 (this is mandatory, sorry), then apply an expand filter which won't expand anything (-1: default), but apply the normal OSD onto the picture (that's what the "1" at the end does).

`-ac hwac3`

  The em8300 supports playing back AC3 audio (surround sound) through the digital audio output of the card. See the `-ao oss` option above, it must be used to specify the DXR3's output instead of a sound card.

#### 2.3.1.4. Other visualization hardware

##### 2.3.1.4.1. 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, the 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 command line is

    mplayer -vo zr -sws 0 -vf 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, then 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 -vf crop=720:320:80:0 benhur.avi

Extra occurrences 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 left 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 build 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.

##### 2.3.1.4.2. Blinkenlights

This driver is capable of playback using the Blinkenlights UDP protocol. If you don't know what Blinkenlights or its successor Arcade are, find it out. Although this is most probably the least used video output driver, without a doubt it is the coolest MPlayer has to offer. Just watch some of the Blinkenlights documentation videos. On the Arcade video you can see the Blinkenlights output driver in action at 00:07:50.

#### 2.3.1.5. TV-out support

##### 2.3.1.5.1. Matrox G400 cards

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

### Важно

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

XFree86

  Using the driver and the HAL module, available from the Matrox site. This will give you X on the TV.

  This method doesn't give you accelerated playback as under Windows! The second head has only YUV framebuffer, the BES (Back End Scaler, the YUV scaler on G200/G400/G450/G550 cards) doesn't work on it! The windows driver somehow workarounds this, probably by using the 3D engine to zoom, and the YUV framebuffer to display the zoomed image. If you really want to use X, use the `-vo x11 -fs -zoom` options, but it will be SLOW, and has Macrovision copy protection enabled (you can "workaround" Macrovision using this perl script).

Framebuffer

  Using the matroxfb modules in the 2.4 kernels. 2.2 kernels don't have the TVout feature in them, thus unusable for this. You have to enable ALL matroxfb-specific feature during compilation (except MultiHead), and compile them into modules! You'll also need I2C enabled.

  1. Enter `TVout` and type ./compile.sh. Install `TVout/matroxset/matroxset` somewhere into your `PATH`.

  2. If you don't have fbset installed, put `TVout/fbset/fbset` somewhere into your `PATH`.

  3. If you don't have con2fb installed, put `TVout/con2fb/con2fb` somewhere into your `PATH`.

  4. Then enter into the `TVout/` directory in the MPlayer source, and execute `./modules` as root. Your text-mode console will enter into framebuffer mode (no way back!).

  5. Next, EDIT and run the `./matroxtv` script. This will present you to a very simple menu. Press 2 and Enter. Now you should have the same picture on your monitor, and TV. If the TV (PAL by default) picture has some weird stripes on it, the script wasn't able to set the resolution correctly (to 640x512 by default). Try other resolutions from the menu and/or experiment with fbset.

  6. Yoh. Next task is to make the cursor on tty1 (or whatever) to disappear, and turn off screen blanking. Execute the following commands:

         echo -e '\033[?25l'
         setterm -blank 0

     or

         setterm -cursor off
         setterm -blank 0

     You possibly want to put the above into a script, and also clear the screen. To turn the cursor back:

         echo -e '\033[?25h'

     or

         setterm -cursor on

  7. Yeah kewl. Start movie playing with

         mplayer -vo mga -fs -screenw 640 -screenh 512 filename

     (If you use X, now change to matroxfb with for example Ctrl+Alt+F1.) Change `640` and `512` if you set the resolution to other...

  8. Enjoy the ultra-fast ultra-featured Matrox TV output (better than Xv)!

Building a Matrox TV-out cable. No one takes any responsibility, nor guarantee for any damage caused by this documentation.

Cable for G400. The CRTC2 connector's fourth pin is the composite video signal. The ground are the sixth, seventh and eighth pins. (info contributed from Balázs Rácz)

Cable for G450. The CRTC2 connector's first pin is the composite video signal. The ground are the fifth, sixth, seventh, and fifteenth (5, 6, 7, 15) pins. (info contributed from Balázs Kerekes)

##### 2.3.1.5.2. 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://www.bglug.ca/matrox_tvout/

##### 2.3.1.5.3. 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

- ATI Mach64: supported by GATOS.
- ASIC Radeon VIVO: supported by GATOS.
- Radeon and Rage128: supported by MPlayer! Check VESA driver and VIDIX sections.
- Rage Mobility P/M, Radeon, Rage 128, Mobility M3/M4: supported by atitvout.

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

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

##### 2.3.1.5.4. Voodoo 3

Check this URL.

##### 2.3.1.5.5. nVidia

First, you MUST download the closed-source drivers from http://nvidia.com. I will not describe the installation and configuration process because it does not cover the scope of this documentation.

After XFree86, XVideo, and 3D acceleration is properly working, edit your card's Device section in the `XF86Config` file, according to the following example (adapt for your card/TV):

    Section "Device"
            Identifier      "GeForce"
            VendorName      "ASUS"
            BoardName       "nVidia GeForce2/MX 400"
            Driver          "nvidia"
            #Option         "NvAGP" "1"
            Option          "NoLogo"
            Option          "CursorShadow"  "on"

            Option          "TwinView"
            Option          "TwinViewOrientation" "Clone"
            Option          "MetaModes" "1024x768,640x480"
            Option          "ConnectedMonitor" "CRT, TV"
            Option          "TVStandard" "PAL-B"
            Option          "TVOutFormat" "Composite"

    EndSection

Of course the important thing is the TwinView part.

##### 2.3.1.5.6. Neomagic

The Neomagic chip is found in a variety of laptops, some of them are equipped with a simple analog TV encoder, some have a more advanced one.

- Analog encoder chip: Tested on a Toshiba Tecra 8000. Its TV output chip is miserable crap. Avoid if possible.

  You must use `-vo vesa`. The tested chip was capable of 1.333333 aspect ratio only, so be sure to use the `-x`, `-y` options and/or the `-vf scale,crop,expand` filters if the box doesn't let you enable TV output. Maximum resolution was 720*576 at 16bpp.

  Known issues: VESA-only, 1.33333 limitation, image isn't always centered, movie becomes 4bpp in every 10 minutes, and stays that way. Frequent hard freezes, LCD display problems.

- Chrontel 70xx encoder chip: Found in IBM Thinkpad 390E and possibly other Thinkpads or notebooks.

  You must use `-vo vesa:neotv_pal` for PAL or `-vo vesa:neotv_ntsc` for NTSC. It will provide TV output function in the following 16 bpp and 8 bpp modes:

  - NTSC 320x240, 640x480 and maybe 800x600 too.
  - PAL 320x240, 400x300, 640x480, 800x600.

  Mode 512x384 is not supported in BIOS. You must scale the image to a different resolution to activate TV out. If you can see an image on the screen in 640x480 or in 800x600 but not in 320x240 or other smaller resolution you need to replace two tables in `vbelib.c`. See the vbeSetTV function for details. Please contact the author in this case.

  Known issues: VESA-only, no other controls such as brightness, contrast, blacklevel, flickfilter are implemented.

### 2.3.2. Audio output devices

#### 2.3.2.1. Audio/Video synchronisation

MPlayer's audio interface is called libao2. It currently contains these drivers:

Driver | Comment
--- | ---
oss | OSS (ioctl) driver (supports hardware AC3 passthrough)
sdl | SDL driver (supports sound daemons like ESD and ARTS)
nas | NAS (Network Audio System) driver
alsa5 | native ALSA 0.5 driver
alsa9 | native ALSA 0.9 driver (supports hardware AC3 passthrough)
sun | SUN audio driver (`/dev/audio`) for BSD and Solaris8 users
macosx | native MacOSX driver
win32 | native Win32 driver
arts | native ARTS driver (mostly for KDE users)
esd | native ESD driver (mostly for GNOME users)
jack | JACK (Jack Audio Connection Kit) driver

Linux sound card drivers have compatibility problems. This is because MPlayer relies on an in-built feature of properly coded sound drivers that enable them to maintain correct audio/video sync. Regrettably, some driver authors don't take the care to code this feature since it is not needed for playing MP3s or sound effects.

Other media players like aviplay or xine possibly work out-of-the-box with these drivers because they use "simple" methods with internal timing. Measuring showed that their methods are not as efficient as MPlayer's.

Using MPlayer with a properly written audio driver will never result in A/V desyncs related to the audio, except only with very badly created files (check the man page for workarounds).

If you happen to have a bad audio driver, try the `-autosync` option, it should sort out your problems. See the man page for detailed information.

Some notes:

- If you have an OSS driver, first try `-ao oss` (this is the default). If you experience glitches, halts or anything out of the ordinary, try `-ao sdl` (NOTE: you need to have SDL libraries and header files installed). The SDL audio driver helps in a lot of cases and also supports ESD (GNOME) and ARTS (KDE).

- If you have ALSA version 0.5, then you almost always have to use `-ao alsa5`, since ALSA 0.5 has buggy OSS emulation code, and will crash MPlayer with a message like this:

      DEMUXER: Too many (945 in 8390980 bytes) video packets in the buffer!

- On Solaris, use the SUN audio driver with the `-ao sun` option, otherwise neither video nor audio will work.

- If the sound clicks when playing from CD-ROM, turn on IRQ unmasking, e.g. hdparm -u1 /dev/cdrom (man hdparm). This is generally beneficial and described in more detail in the CD-ROM section.

#### 2.3.2.2. Soundcard experiences, recommendations

On Linux, a 2.4.x kernel is highly recommended. Kernel 2.2 is not tested.

Linux sound drivers are primarily provided by the free version of OSS. These drivers have been superseded by ALSA (Advanced Linux Sound Architecture) in the 2.5 development series. If your distribution does not already use ALSA you may wish to try their drivers if you experience sound problems. ALSA drivers are generally superior to OSS in compatibility, performance and features. But some sound cards are only supported by the commercial OSS drivers from 4Front Technologies. They also support several non-Linux systems.

SOUND CARD | DRIVER | Max kHz | Max Channels | Max Opens [a]
--- | --- | --- | --- | ---
OSS/Free | ALSA | OSS/Pro | other
VIA onboard (686/A/B, 8233, 8235) | via82cxxx_audio | snd-via82xx |  |  | 4-48 kHz or 48 kHz only, depending on the chipset |  |
Aureal Vortex 2 | none | none | OK | Linux Aureal Drivers buffer size increased to 32k | 48 | 4.1 | 5+
SB Live! | Analog OK, S/PDIF not working | Both OK | Both OK | Creative's OSS driver (S/PDIF support) | 192 | 4.0/5.1 | 32
SB 128 PCI (es1371) | OK | ? |  |  | 48 | stereo | 2
SB AWE 64 | max 44kHz | 48kHz sounds bad |  |  | 48 |  |
GUS PnP | none | OK | OK |  | 48 |  |
Gravis UltraSound ACE |  |  |  |  |  |  |
Gravis UltraSound MAX | OK | OK (?) |  |  | 48 |  |
ESS 688 | OK | OK (?) |  |  | 48 |  |
C-Media cards (CMI8338/8738) | OK | OK S/PDIF is supported with ALSA 0.9.x | ? |  | 44 | stereo | 1
Yamaha cards (*ymf*) | not OK (?) (maybe `-ao sdl`) | OK only with ALSA 0.5 with OSS emulation AND`-ao sdl` (!) (?) |  |  |  |  |
Cards with envy24 chips (like Terratec EWS88MT) | ? | ? | OK |  | ? |  |
PC Speaker or DAC | OK | none |  | Linux PC speaker OSS driver | The driver emulates 44.1, maybe more. | mono | 1
[a] [a] the number of applications that are able to use the device at the same time.

Feedback to this document is welcome. Please tell us how MPlayer and your sound card(s) worked together.

#### 2.3.2.3. Audio filters

The old audio plugins have been superseded by a new audio filter layer. Audio filters are used for changing the properties of the audio data before the sound reaches the sound card. The activation and deactivation of the filters is normally automated but can be overridden. The filters are activated when the properties of the audio data differ from those required by the sound card and deactivated if unnecessary. The `-af filter1,filter2,...` option is used to override the automatic activation of filters or to insert filters that are not automatically inserted. The filters will be executed as they appear in the comma separated list.

Example:

    mplayer -af resample,pan movie.avi

would run the sound through the resampling filter followed by the pan filter. Observe that the list must not contain any spaces, else it will fail.

The filters often have options that change their behavior. These options are explained in detail in the sections below. A filter will execute using default settings if its options are omitted. Here is an example of how to use filters in combination with filter specific options:

    mplayer -af resample=11025,pan=1:0.5:0.5 -channels 1 -srate 11025 media.avi

would set the output frequency of the resample filter to 11025Hz and downmix the audio to 1 channel using the pan filter.

The overall execution of the filter layer is controlled using the `-af-adv` option. This option has two suboptions:

`force` is a bit field that controls how the filters are inserted and what speed/accuracy optimizations they use:

`0`

  Use automatic insertion of filters and optimize according to CPU speed.

`1`

  Use automatic insertion of filters and optimize for the highest speed. Warning: Some features in the audio filters may silently fail, and the sound quality may drop.

`2`

  Use automatic insertion of filters and optimize for quality.

`3`

  Use no automatic insertion of filters and no optimization. Warning: It may be possible to crash MPlayer using this setting.

`4`

  Use automatic insertion of filters according to 0 above, but use floating point processing when possible.

`5`

  Use automatic insertion of filters according to 1 above, but use floating point processing when possible.

`6`

  Use automatic insertion of filters according to 2 above, but use floating point processing when possible.

`7`

  Use no automatic insertion of filters according to 3 above, and use floating point processing when possible.

`list` is an alias for the -af option.

The filter layer is also affected by the following generic options:

`-v`

  Increases the verbosity level and makes most filters print out extra status messages.

`-channels`

  This option sets the number of output channels you would like your sound card to use. It also affects the number of channels that are being decoded from the media. If the media contains less channels than requested the channels filter (see below) will automatically be inserted. The routing will be the default routing for the channels filter.

`-srate`

  This option selects the sample rate you would like your sound card to use (of course the cards have limits on this). If the sample frequency of your sound card is different from that of the current media, the resample filter (see below) will be inserted into the audio filter layer to compensate for the difference.

`-format`

  This option sets the sample format between the audio filter layer and the sound card. If the requested sample format of your sound card is different from that of the current media, a format filter (see below) will be inserted to rectify the difference.

##### 2.3.2.3.1. Up/Downsampling

MPlayer fully supports sound up/down-sampling through the `resample` filter. It can be used if you have a fixed frequency sound card or if you are stuck with an old sound card that is only capable of max 44.1kHz. This filter is automatically enabled if it is necessary, but it can also be explicitly enabled on the command line. It has three options:

`srate <8000-192000>`

  is an integer used for setting the output sample frequency in Hz. The valid range for this parameter is 8kHz to 192kHz. If the input and output sample frequency are the same or if this parameter is omitted the filter is automatically unloaded. A high sample frequency normally improves the audio quality, especially when used in combination with other filters.

`sloppy`

  is an optional binary parameter that allows the output frequency to differ slightly from the frequency given by `srate`. This option can be used if the startup of the playback is extremely slow. It is enabled by default.

`type <0-2>`

  is an optional integer between `0` and `2` that selects which resampling method to use. Here `0` represents linear interpolation as resampling method, `1` represents resampling using a poly-phase filter-bank and integer processing and `2` represents resampling using a poly-phase filter-bank and floating point processing. Linear interpolation is extremely fast, but suffers from poor sound quality especially when used for up-sampling. The best quality is given by `2` but this method also suffers from the highest CPU load.

Example:

    mplayer -af resample=44100:0:0

would set the output frequency of the resample filter to 44100Hz using exact output frequency scaling and linear interpolation.

##### 2.3.2.3.2. Changing the number of channels

The `channels` filter can be used for adding and removing channels, it can also be used for routing or copying channels. It is automatically enabled when the output from the audio filter layer differs from the input layer or when it is requested by another filter. This filter unloads itself if not needed. The number of options is dynamic:

`nch <1-6>`

  is an integer between `1` and `6` that is used for setting the number of output channels. This option is required, leaving it empty results in a runtime error.

`nr <1-6>`

  is an integer between `1` and `6` that is used for specifying the number of routes. This parameter is optional. If it is omitted the default routing is used.

`from1:to1:from2:to2:from3:to3...`

  are pairs of numbers between `0` and `5` that define where each channel should be routed.

If only `nch` is given the default routing is used, it works as follows: If the number of output channels is bigger than the number of input channels empty channels are inserted (except mixing from mono to stereo, then the mono channel is repeated in both of the output channels). If the number of output channels is smaller than the number of input channels the exceeding channels are truncated.

Example 1:

    mplayer -af channels=4:4:0:1:1:0:2:2:3:3 media.avi

would change the number of channels to 4 and set up 4 routes that swap channel 0 and channel 1 and leave channel 2 and 3 intact. Observe that if media containing two channels was played back, channels 2 and 3 would contain silence but 0 and 1 would still be swapped.

Example 2:

    mplayer -af channels=6:4:0:0:0:1:0:2:0:3 media.avi

would change the number of channels to 6 and set up 4 routes that copy channel 0 to channels 0 to 3. Channel 4 and 5 will contain silence.

##### 2.3.2.3.3. Sample format converter

The `format` filter converts between different sample formats. It is automatically enabled when needed by the sound card or another filter.

`bps <number>`

  can be `1`, `2` or `4` and denotes the number of bytes per sample. This option is required, leaving it empty results in a runtime error.

`f <format>`

  is a text string describing the sample format. The string is a concatenated mix of: `alaw`, `mulaw` or `imaadpcm`, `float` or `int`, `unsigned` or `signed`, `le` or `be` (little or big endian). This option is required, leaving it empty results in a runtime error.

Example:

    mplayer -af format=4:float media.avi

would set the output format to 4 bytes per sample floating point data.

##### 2.3.2.3.4. Delay

The `delay` filter delays the sound to the loudspeakers such that the sound from the different channels arrives at the listening position simultaneously. It is only useful if you have more than 2 loudspeakers. This filter has a variable number of parameters:

`d1:d2:d3...`

  are floating point numbers representing the delays in ms that should be imposed on the different channels. The minimum delay is 0ms and the maximum is 1000ms.

To calculate the required delay for the different channels do as follows:

1. Measure the distance to the loudspeakers in meters in relation to your listening position, giving you the distances s1 to s5 (for a 5.1 system). There is no point in compensating for the sub-woofer (you will not hear the difference anyway).

2. Subtract the distances s1 to s5 from the maximum distance i.e. s[i] = max(s) - s[i]; i = 1...5

3. Calculate the required delays in ms as d[i] = 1000*s[i]/342; i = 1...5

Example:

    mplayer -af delay=10.5:10.5:0:0:7:0 media.avi

would delay front left and right by 10.5ms, the two rear channels and the sub by 0ms and the center channel by 7ms.

##### 2.3.2.3.5. Software volume control

Software volume control is implemented by the `volume` audio filter. Use this filter with caution since it can reduce the signal to noise ratio of the sound. In most cases it is best to set the level for the PCM sound to max, leave this filter out and control the output level to your speakers with the master volume control of the mixer. In case your sound card has a digital PCM mixer instead of an analog one, and you hear distortion, use the MASTER mixer instead. If there is an external amplifier connected to the computer (this is almost always the case), the noise level can be minimized by adjusting the master level and the volume knob on the amplifier until the hissing noise in the background is gone. This filter has two options:

`v <-200 - +60>`

  is a floating point number between `-200` and `+60` which represents the volume level in dB. The default level is 0dB.

`c`

  is a binary control that turns soft clipping on and off. Soft-clipping can make the sound more smooth if very high volume levels are used. Enable this option if the dynamic range of the loudspeakers is very low. Be aware that this feature creates distortion and should be considered a last resort.

Example:

    mplayer -af volume=10.1:0 media.avi

would amplify the sound by 10.1dB and hard-clip if the sound level is too high.

This filter has a second feature: It measures the overall maximum sound level and prints out that level when MPlayer exits. This volume estimate can be used for setting the sound level in MEncoder such that the maximum dynamic range is utilized.

##### 2.3.2.3.6. Equalizer

The `equalizer` filter represents a 10 octave band graphic equalizer, implemented using 10 IIR band pass filters. This means that it works regardless of what type of audio is being played back. The center frequencies for the 10 bands are:

Band No. | Center frequency
--- | ---
0 | 31.25 Hz
1 | 62.50 Hz
2 | 125.0 Hz
3 | 250.0 Hz
4 | 500.0 Hz
5 | 1.000 kHz
6 | 2.000 kHz
7 | 4.000 kHz
8 | 8.000 kHz
9 | 16.00 kHz

If the sample rate of the sound being played back is lower than the center frequency for a frequency band, then that band will be disabled. A known bug with this filter is that the characteristics for the uppermost band are not completely symmetric if the sample rate is close to the center frequency of that band. This problem can be worked around by up-sampling the sound using the resample filter before it reaches this filter.

This filter has 10 parameters:

`g1:g2:g3...g10`

  are floating point numbers between `-12` and `+12` representing the gain in dB for each frequency band.

Example:

    mplayer -af equalizer=11:11:10:5:0:-12:0:5:12:12 media.avi

would amplify the sound in the upper and lower frequency region while canceling it almost completely around 1kHz.

##### 2.3.2.3.7. Panning filter

Use the `pan` filter to mix channels arbitrarily. It is basically a combination of the volume control and the channels filter. There are two major uses for this filter:

1. Down-mixing many channels to only a few, stereo to mono for example.

2. Varying the "width" of the center speaker in a surround sound system.

This filter is hard to use, and will require some tinkering before the desired result is obtained. The number of options for this filter depends on the number of output channels:

`nch <1-6>`

  is an integer between `1` and `6` and is used for setting the number of output channels. This option is required, leaving it empty results in a runtime error.

`l00:l01:l02:..l10:l11:l12:...ln0:ln1:ln2:...`

  are floating point values between `0` and `1`. `l[i][j]` determines how much of input channel j is mixed into output channel i.

Example 1:

    mplayer -af pan=1:0.5:0.5 -channels 1 media.avi

would down-mix from stereo to mono.

Example 2:

    mplayer -af pan=3:1:0:1:0.5:0.5 -channels 3 media.avi

would give 3 channel output leaving channels 0 and 1 intact, and mix channels 0 and 1 into output channel 2 (which could be sent to a sub-woofer for example).

##### 2.3.2.3.8. Sub-woofer

The `sub` filter adds a sub woofer channel to the audio stream. The audio data used for creating the sub-woofer channel is an average of the sound in channel 0 and channel 1. The resulting sound is then low-pass filtered by a 4th order Butterworth filter with a default cutoff frequency of 60Hz and added to a separate channel in the audio stream. Warning: Disable this filter when you are playing DVDs with Dolby Digital 5.1 sound, otherwise this filter will disrupt the sound to the sub-woofer. This filter has two parameters:

`fc <20-300>`

  is an optional floating point number used for setting the cutoff frequency for the filter in Hz. The valid range is 20Hz to 300Hz. For the best result try setting the cutoff frequency as low as possible. This will improve the stereo or surround sound experience. The default cutoff frequency is 60Hz.

`ch <0-5>`

  is an optional integer between `0` and `5` which determines the channel number in which to insert the sub-channel audio. The default is channel number `5`. Observe that the number of channels will automatically be increased to `ch` if necessary.

Example:

    mplayer -af sub=100:4 -channels 5 media.avi

would add a sub-woofer channel with a cutoff frequency of 100Hz to output channel 4.

##### 2.3.2.3.9. Surround-sound decoder

Matrix encoded surround sound can be decoded by the `surround` filter. Dolby Surround is an example of a matrix encoded format. Many files with 2 channel audio actually contain matrixed surround sound. To use this feature you need a sound card supporting at least 4 channels. This filter has one parameter:

`d <0-1000>`

  is an optional floating point number between `0` and `1000` used for setting the delay time in ms for the rear speakers. This delay should be set as follows: if d1 is the distance from the listening position to the front speakers and d2 is the distance from the listening position to the rear speakers, then the delay d should be set to 15ms if d1 <= d2 and to 15 + 5*(d1-d2) if d1 > d2. The default value for d is 20ms.

Example:

    mplayer -af surround=15 -channels 4 media.avi

would add surround sound decoding with 15ms delay for the sound to the rear speakers.

##### 2.3.2.3.10. Audio Exporter

This audio filter exports the incoming signal to other processes using memory mapping (`mmap()`). Memory mapped areas contain a header:

    int nch                      /*number of channels*/
    int size		     /*buffer size*/
    unsigned long long counter   /*Used to keep sync, it's updated
                                   every time new data is exported.*/

The rest is payload (non-interleaved) 16bit data.

`mmapped_file`

  The file you want this filter to export to. The default is to map to `~/.mplayer/mplayer-af_export`.

`nsamples`

  Number of samples per channel. The default is `512` samples.

Example:

    mplayer -af export=/tmp/mplayer-af_export:1024 media.avi

would export 1024 samples per channel to `/tmp/mplayer-af_export`.

#### 2.3.2.4. Audio plugins (deprecated)

### Замечание

Audio plugins have been deprecated by audio filters and will be removed soon.

MPlayer has support for audio plugins. Audio plugins can be used for changing the properties of the audio data before the sound reaches the sound card. They are enabled using the `-aop` switch which takes a `list=plugin1,plugin2,...` argument. The `list` argument is required and determines which plugins should be used and in which order they should be executed. Example:

    mplayer media.avi -aop list=resample,format

would run the sound through the resampling plugin followed by the format plugin.

The plugins can also have switches that change their behavior. These switches are explained in detail in the sections below. A plugin will execute using default settings if its switches are omitted. Here is an example of how to use plugins in combination with plugin specific switches:

    mplayer media.avi -aop list=resample,format:fout=44100:format=0x8

would set the output frequency of the resample plugin to 44100 Hz and the output format of the format plugin to AFMT_U8.

Currently audio plugins can not be used in MEncoder.

##### 2.3.2.4.1. Up/Downsampling

MPlayer fully supports up/downsampling of the sound. This plugin can be used if you have a fixed frequency sound card or if you are stuck with an old sound card that is only capable of max 44.1 kHz. Limitations in your hardware are not auto detected, so you have to specify the sample frequency explicitly. This plugin has one switch: `fout` which is used for setting the desired output sample frequency. It defaults to 48 kHz, and is given in Hz.

Usage:

    mplayer media.avi -aop list=resample:fout=freq

where ``freq`` is the frequency in Hz, like `44100`.

### Замечание

The output frequency should not be scaled up from the default value. Scaling up will cause the audio and video streams to be played in slow motion in addition to audio distortion.

##### 2.3.2.4.2. Surround Sound decoding

MPlayer has an audio plugin that can decode matrix encoded surround sound. Dolby Surround is an example of a matrix encoded format. Many files with 2 channel audio actually contain matrixed surround sound. To use this feature you need a sound card supporting at least 4 channels.

Usage:

    mplayer media.avi -aop list=surround

##### 2.3.2.4.3. Sample format converter

If your sound card driver does not support signed 16-bit int data type, this plugin can be used to change the format to one which your sound card can understand. It has one switch, `format`, which can be set to one of the numbers found in `libao2/afmt.h`. This plugin is hardly ever needed and is intended for advanced users. Keep in mind that this plugin only changes the sample format and not the sample frequency or the number of channels.

Usage:

    mplayer media.avi -aop list=format:format=outfmt

where ``outfmt`` is the required output format.

##### 2.3.2.4.4. Delay

This plugin delays the sound and is intended as an example of how to develop new plugins. It can not be used for anything useful from a users perspective and is mentioned here for the sake of completeness only. Do not use this plugin unless you are a developer.

##### 2.3.2.4.5. Software volume control

This plugin is a software replacement for the volume control, and can be used on machines with a broken mixer device. It can also be used if one wants to change the output volume of MPlayer without changing the PCM volume setting in the mixer. It has one switch `volume` that is used for setting the initial sound level. The initial sound level can be set to values between 0 and 255 and defaults to 101 which equals 0dB amplification. Use this plugin with caution since it can reduce the signal to noise ratio of the sound. In most cases it is best to set the level for the PCM sound to max, leave this plugin out and control the output level to your speakers with the master volume control of the mixer. If there is an external amplifier connected to the computer (this is almost always the case), the noise level can be minimized by adjusting the master level and the volume knob on the amplifier until the hissing noise in the background is gone.

Usage:

    mplayer media.avi -aop list=volume:volume=0-255

This plugin also has compressor or "soft-clipping" capabilities. Compression can be used if the dynamic range of the sound is very high or if the dynamic range of the loudspeakers is very low. Be aware that this feature creates distortion and should be considered a last resort.

Usage:

    mplayer media.avi -aop list=volume:softclip

##### 2.3.2.4.6. Extrastereo

This plugin (linearly) increases the difference between left and right channels (like the XMMS extrastereo plugin) which gives some sort of "live" effect to playback.

Usage:

    mplayer media.avi -aop list=extrastereo
    mplayer media.avi -aop list=extrastereo:mul=3.45

The default coefficient (`mul`) is a float number that defaults to 2.5. If you set it to `0.0`, you will have mono sound (average of both channels). If you set it to `1.0`, sound will be unchanged, if you set it to `-1.0`, left and right channels will be swapped.

##### 2.3.2.4.7. Volume normalizer

This plugin maximizes the volume without distorting the sound.

Usage:

    mplayer media.avi -aop list=volnorm

Пред. | Уровень выше | След.
2.2. Поддерживаемые кодеки | Начало | 2.4. TV вход