2.2.1.  Video output devices   

  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.

  o with XFree 4.0.3 and nv.o there is a bug resulting in strange colors
  o ATI driver requires to switch mode back more than once after finishing 
    using of DGA
  o some drivers simply fail to switch back to normal resolution (use 
    Ctrl-Alt-Keypad +, - to switch back manually)
  o some drivers simply display strange colors
  o some drivers lie about the amount of memory they map into the process's
    address space, thus vo_dga won't use doublebuffering (SIS?)
  o 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 ...
  o OSD only works with doublebuffering enabled


  2.2.1.3.9.  Future work

  o use of the new X11 render interface for OSD
  o 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
	monitor_vfreq		IMPORTANT values, see example.conf
	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
	fbdev 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!
	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:

  1. 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)

  2. 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! :(

  -  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.