Videocards with hardware acceleration:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

* read DOCS/MTRR too!

  "Hardware acceleration" usually means hardware YUV conversion, scaling,
bilinear filtering. Under Linux, there are several ways to access it:

I.   The Xv (XVideo) extension of XFree86 4.0.2
II.  OpenGL drivers with glTexSubImage() support (currently the Utah-GLX
     drivers)
III. Native card-specific drivers, using special abilities of some cards
IV.  DGA - direct graphic access. no YUV & scaling, but faster than raw X11

Now, let's see them in details:

I. Under XFree86 4.0.2 or newer, using the XVideo extension:
   this is what the option '-vo xv' uses.

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

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

2. Your card actually supports harware 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
   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!

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. Be sure MPlayer is compiled with the "xv" target. "./configure" should say:
	Checking for Xv ... yes

6. If all is fine, try the option '-vo xv' . It should work.
   (if it doesn't, send us a bugreport. See the README on how to do this.)


II. OpenGL drivers with *working* *fast* glTexSubImage() support.

   Currently only the old Utah-GLX drivers (for X 3.3.6) have it.
   See http://utah-glx.sourceforge.net for details about how to install it.

   The new X4/DRI and nVidia's binary drivers has no usable glTexSubImage :(

III. Native card-specific drivers

There is 3 native drivers for Linux:
1. Matrox G200/G400/G450 BES (Back-End Scaler) support -> mga_vid kernel drv.
  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, simply compile the mga_vid.o in the drivers/ subdir (type: make)
  and load it 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

  Using it from MPlayer:  (you should re-compile it with mga_vid support...)
  
  Use the 'mga' vo driver on framebuffer console (matroxfb): -vo mga
  and use the xmga driver for X 3.3.x: -vo xmga

  Note: it works under X 4.0.2 too, but it conflicts with the Xv driver,
  so avoid using both. Usually X restart or reboot needs to get Xv usable
  again :(

2. 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.

3. 3dfx (which ones?) 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.


IV. If your card lacks hardware acceleration, you can still boost your fps by
using the DGA driver:

1. Make sure X loads the DGA extension:
	(II) Loading extension XFree86-DGA
2. MPlayer's DGA driver is autodetected on ./configure, or you can force it
   with --enable-dga.
3. Be sure to use 24/32bpp mode, since there is no converter right now.. :(
4. 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 ... !!!!

5. Use '-vo dga' option, and there you go! (hope so:)

If you have fast enough CPU (P3 800 for example) you can try fsdga for
fullscreen mpeg playing (using software YUV->RGB scaling):
mplayer -vo fsdga ...



	Gabucino & A'rpi