General:
	x11	X11 with optional SHM extension
	xv	X11 using overlays with the Xvideo extension (hardware YUV & scaling)
	gl	OpenGL renderer, so far works only with: all cards with Utah-GLX Matrox cards with X/DRI >=4.0.3 Radeon with X/DRI CVS
	dga	X11 DGA extension
	fbdev	Output to general framebuffers
	svga	Output to SVGAlib
	sdl	`1.1.7:` supports software scaling `1.1.8:` supports Xvideo (hardware scaling/fullscreen) `1.2.0:` supports AAlib (-vo aa is very recommended, see below!)
	ggi	similar to SDL
	aa	textmode rendering with AAlib
Card specific:
	mga	Matrox G200/G400 hardware YUV overlay via the mga_vid device
	xmga	Matrox G200/G400 overlay (mga_vid) in X11 window (Xv emulation on X 3.3.x!)
	syncfb	Matrox G400 YUV support on framebuffer (obsoleted, use mga/xmga)
	3dfx	Voodoo2/3 hardware YUV (/dev/3dfx) support (not yet tested, maybe broken)
Special:
	png	PNG files output (use -z switch to set compression)
	pgm	PGM files output (for testing purposes or ffmpeg encoding)
	md5	MD5sum output (for MPEG conformance tests)
	odivx	OpenDivX AVI File writer (use -br to set encoding bitrate)
	null	Null output (for speed tests/benchmarking)

NOTE: check the following subsections for details and requirements!

2.2.1.1. MTRR

It is VERY recommended to set MTRR registers up properly, because they can give a big performance boost. First you have to find the base address. You have 3 ways to find it:

from X11 startup messages, for example:
(--) SVGA: PCI: Matrox MGA G400 AGP rev 4, Memory @ 0xd8000000, 0xd4000000 (--) SVGA: Linear framebuffer at 0xD8000000
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)
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 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').

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

You have to use XFree86 4.0.2 or newer (former versions don't have XVideo)
Your card actually supports harware acceleration (modern cards do)
X loads the XVideo extension, it's something like this:
(II) Loading extension XVideo

in /var/log/XFree86.0.log

NOTE: 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!

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.

And finally, check if MPlayer was compiled with 'xv' support. ./configure prints this.

2.2.1.2.1. 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 4.1.0 or greater, it works ok. Alternatively, you can use DRI cvs. 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.

2.2.1.2.2. S3 cards

S3 Savage3D's should work fine, but for Savage4, use XFree86 version 4.0.3 or greater. As for S3 Virge.. sell it.

2.2.1.2.3. nVidia cards

nVidia isn't a very good choice under Linux.. You'll have to use the binary nVidia driver, available at nVidia's website. The standard X driver doesn't support XVideo for these cards, due to nVidia's closed sources/specifications.

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

2.2.1.2.4. ATI cards

The GATOS driver 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 n*(fps of the movie) Hz.

2.2.1.3. DGA

2.2.1.3.1. 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).

2.2.1.3.2. 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 excecutable (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 XServer, 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 XServer's video driver that controls this chip. So it does not work on every system ...

2.2.1.3.3. 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 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.


!!!! BUT STAY TUNED !!!!

This is a BIG security risk! Never do this on a server or on a computer
can be accessed by more people than only you because they can gain root
privilegies through suid root mplayer.

!!!! SO YOU HAVE BEEN WARNED ... !!!!

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!!!

2.2.1.3.4. 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 honouring aspect ratio) of the video data, but the
XServer 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 capabilites
of your video hardware. The XServer 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.

2.2.1.3.5. 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.

2.2.1.3.6. Features of the DGA driver
 
The DGA driver is invoked by specifying -vo dga at the command line.
The default behaviour 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.
 

2.2.1.3.7. 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.

2.2.1.3.8. Known bugs

Well, according to some developpers 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 +, - 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 the like ...
OSD only works with doublebuffering enabled


2.2.1.3.9. Future work

use of the new X11 render interface for OSD
where is my TODO list ???? :-(((



2.2.1.3.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 XServer driver
module.


2.2.1.3.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)


2.2.1.4. SDL

Here are some notes about SDL out in MPlayer.




There are several commandline switches for SDL:

   -vo sdl:name    
specifies sdl video driver to use (ie. aalib, dga, x11)

-ao sdl:name specifies sdl audio driver to use (ie. dsp,
esd, arts)

-noxv disables Xvideo hardware acceleration

-forcexv tries to force Xvideo acceleration


SDL Keys:


F toggles fullscreen/windowed mode

C cycles available fullscreen modes

W/S mappings for * and / (mixer control)




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).


2.2.1.5. SVGAlib

If you don't have X, you can use the SVGAlib target! Be sure not to use the
-fs switch, since it toggles the usage of the software scaler, and it's
SLOOOW now, unless you have a real fast CPU (and/or MTRR?). :(

Of course 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.

2.2.1.6. Framebuffer output (FBdev)

Whether to build the FBdev target is autodetected during ./configure .
Read the framebuffer documentation in the kernel sources
(Documentation/fb/*) for info on how to enable it, etc.. !

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/fd0)

-fbmode mode name to use (according to /etc/fb.modes)

-fbmodeconfig 	config file of modes (default /etc/fb.modes)

-monitor_hfreq IMPORTANT values, see example.conf

-monitor_vfreq 
		
-monitor_dotclock 



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

    mplayer -vm -fbmode (NameOfMode) 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 (software scaling is slow). -fs option
isn't supported. You can't use 8bpp (or less) modes.


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.

2.2.1.7. Matrox framebuffer (mga_vid)

This section is about the Matrox G200/G400/G450 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.
  
To use it, you first have to compile mga_vid.o:

    cd drivers

    make

Then create /dev/mga_vid device:

    mknod /dev/mga_vid c 178 0

and load the driver with

    insmod mga_vid.o

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

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

    alias char-major-178 mga_vid

Then run

    depmod -a

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.

Note: '-vo xmga' works under XFree86 4.x.x, but it conflicts with the Xv
driver, so avoid using both. If you messed up Xv with mga, try running
MPlayer with '-vo mga' . It should fix Xv.
  

2.2.1.8. SiS 6326 framebuffer (sis_vid)

SiS 6326 YUV Framebuffer driver -> sis_vid kernel driver

Its interface should be compatible with the mga_vid, but the driver was not
updated after the mga_vid changes, so it's outdated now.  Volunteers
needed to test it and bring the code up-to-date.

2.2.1.9. 3dfx YUV support

3dfx has native YUV+scaler support, using /dev/3dfx (tdfx.o driver?)
The /dev/3dfx kernel driver exists only for 2.2.x kernels, for use with
Glide 2.x Linux ports. It's not tested with MPlayer, and so no more
supported. Volunteers needed to test it and bring the code up-to-date.

2.2.1.10. OpenGL output

MPlayer support displaying movies using OpenGL. Unfortunately, not all
drivers support this ability. For example the Utah-GLX drivers
(for XFree86 3.3.6) have it, with all cards.
See http://utah-glx.sourceforge.net
for details about how to install it.

XFree86(DRI) >= 4.0.3 supports it only with Matrox, and Radeon cards.
See http://dri.sourceforge.net for download,
and installation instructions.

2.2.1.11. 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

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

a 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/boldfont, 4/reverse, 5/special)

	      
AAlib itselves 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
bdev to do conversion/dithering to hgafb? Would be neat :)
	
Use the -framedrop option if your comp 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, bu vo_aa tries to find the best mode.
See http://aa-project.sourceforge.net/tune/ for further tuning issues.

2.2.1.A. TV-out support

2.2.1.A.1. Matrox cards

 What I'd love to see in mplayer is the the same feature that I see in my
windows box. When I start a movie in windows (in a window or in full screen)
the movie is also redirected to the tv-out and I can also see it full screen
on my tv. I love this feature and was wondering how hard it would be to add
such a feature to mplayer.

It's a driver limitation. BES (Back-End Scaler, it's the overlay generator
and YUV scaling engine of G200/G400/G450 cards) works only with CRTC1.
Normally, CRTC1 (textmode, every bpp gfx and BES) is routed to HEAD1,
and CRTC2 (only 16/32bpp gfx) is routed to HEAD2 (TV-out).

Under linux, you have two choices to get TV-out working:


Using X 4.0.x + the HAL driver from matrox, so you'll get dual-head
support, and you'll be able to redirect second output to the TV.
Unfortunately it has Macrovision encryption enabled, so it will
only work on directly-connected TV, no through VCR.
Other problem is that Xv doesn't work on the second head.
(I don't know how Windows solve it, maybe it swaps the CRTCs between
the heads, or just uses YUV framebuffer of second DAC with some trick)
Using matroxfb with dual-head support enabled (2.4.x kernels).
You'll be able to get a framebuffer console (using CRTC2, so it's
slow), and TV-out (using CRTC1, with BES support).
You have to forget X while using this kind of TV-out! :(


Follow these instructions:


Compile all the matrox-related things to modules in the kernel.
(you MUST compile them to modules, at least I couldn't get them
working built-in yet)
[reboot to new kernel & install modules, but don't load them yet!]

  cd TVout

  ./compile.sh
Run the 'modules' script from the TV-out directory of mplayer.
It will switch your console to framebuffer.
Change to tty1 (ALT+F1)!
Now run the script 'independent', it will set up your tty's:
tty 1,2:      fb console, CRTC2, head 1 (monitor)

tty 3,4,5...: framebuffer+BES, CRTC1, head 2 (TV-out)
You should run the scripts TV-* and Mon-* to set up resolutions:
change to tty1 (ALT+F1), and run Mon-* (one of them)

change to tty3 (ALT+F3) and then back to tty1 (ALT+F1)
(this change will select tty3 on /dev/fb1 - tricky)

run TV-* (one of them)
(now you'll get a console on your PAL TV - don't know about NTSC)
Now if you start mplayer (on tty1), the picture will show up on
the tty3, so you'll see it on your TV or second monitor.


Yes, it is a bit 'hack' now. But I'm waiting for the marvel
project to be finished, it will provide real TV-out drivers, I hope.

My current problem is that BES is working only with CRTC1. So picture
will always shown up on head routed to CRTC1 (normaly the monitor),
so i have to swap CRTC's, but this way your console will framebuffer
(CRTC2 can't do text-mode) and a bit slow (no acceleration). :(

Anyway i also just get monochrome output on the tv ...
Maybe you have NTSC TV? Or just didn't run one of TV-* scripts.

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

There are several commandline switches for SDL:
	-vo sdl:name	specifies sdl video driver to use (ie. aalib, dga, x11)
	-ao sdl:name	specifies sdl audio driver to use (ie. dsp, esd, arts)
	-noxv	disables Xvideo hardware acceleration
	-forcexv	tries to force Xvideo acceleration
SDL Keys:
	F	toggles fullscreen/windowed mode
	C	cycles available fullscreen modes
	W/S	mappings for * and / (mixer control)

	-fb		specify the framebuffer device to use (/dev/fd0)
	-fbmode		mode name to use (according to /etc/fb.modes)
	-fbmodeconfig		config file of modes (default /etc/fb.modes)
	-monitor_hfreq		IMPORTANT values, see example.conf
	-monitor_vfreq
	-monitor_dotclock

You can use some keys in the AA Window to change rendering options:
	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
	a	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/boldfont, 4/reverse, 5/special)
AAlib itselves 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