$OpenBSD: README,v 1.2 2018/09/04 12:46:28 espie Exp $

+-----------------------------------------------------------------------
| Running ogle on OpenBSD
+-----------------------------------------------------------------------

Due to limitations in OpenBSD, ogle(1) cannot use any audio 5.1 output
system and will always output stereo sound.

As shipped, ogle has a text-based interface. 
The ogle_gui, okle, and goggles yield alternative GUI interfaces.

Video acceleration
==================

To run ogle, you need a graphics card well supported  by Xorg, including
the Xvideo extension in YUV mode, and a sound card with 48KHz output.
You can check your display Xvideo capabilities with "xdpyinfo" (presence
of the Xvideo extension) and "xvinfo" (presence of an adapter with
correct YUV capabilities).

A positive test will usually look like:
xvinfo
    Number of image formats: 4
	...
      id: 0x32315659 (YV12)
        guid: 59563132-0000-0010-8000-00aa00389b71
	...
which is the encoding that ogle(1) is looking for.

Alternately, at the expense of more cpu power, ogle can also use SystemV
shared memory, but the shared memory requirements exceed default GENERIC
parameters. You will need to crank them up. 

Starting with OpenBSD 3.3, sysctl(8) can modify the shared memory 
parameters.  A reasonable choice would be:

kern.shminfo.shmall=32768

(to add to /etc/sysctl.conf, or to tweak manually with sysctl).

Overall, ogle needs about 50% cpu for full-framerate decoding on a
PIII700 with an ATI Mach64 Mobility and an ESS  Maestro 2.

If Xvideo YV12 is not available, ogle roughly needs 120% cpu on the same
machine in 24 bits mode, and full screen rescale  is not available.

On i386, it's highly recommended to go  to a 16 bits mode, where MMX
acceleration code exists (requirements go down to 70% cpu). 

If you can, you may also wish to add several `non-standard' modes to
your xorg.conf. The most useful being 720x576.
