v4l-conf - configure a video4linux driver
v4l-conf [ options ]
is a small helper tool. It figures out the video mode and
framebuffer base address of the graphics board and configures a video4linux
driver like bttv. This is needed for drivers which can DMA the video over PCI
directly into the video memory.
Usually it is not required to use v4l-conf manually, xawtv(1) and fbtv(1) run it
automatically at startup. It might be useful for trouble-shooting.
must be installed suid-root.
knows three ways to get the informations:
- Query the X-Server using the XF86 DGA extension. This is the default if
the DISPLAY environment variable is set.
- Query the framebuffer driver. This is the default if DISPLAY is not
- Query the console driver. This is used on mklinux only.
- Print a short description of all command line options.
- Be quiet.
- -d dpy
- Use the X11 display dpy to get the parameters.
- Use the framebuffer driver to get the parameters.
- -c device
- Set the video4linux device.
- -b n
- enforce n bpp color depth. Works for switching between 15/16 and
- -s n
- Shift the video display by n bytes.
- -a adr
- Set framebuffer address to adr. The value should be specified in
hex. This option is allowed for root only. You can't overwrite the
autodetected value, this switch is only useful if autodetect doesn't work
because the X-Server lacks DGA support. You can put this into
/etc/conf.modules, as "post-install bttv ..." for example.
- -p pitch
- Set framebuffer pitch to pitch bytes. The value should be specified
in decimal. Allowed for root only.
Hope I haven't any security flaws in there. If you find one, drop me a note.
Mails with patches are preferred :-)
Gerd Knorr <firstname.lastname@example.org>
Copyright (C) 1997-99 Gerd Knorr <email@example.com>
This program is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free Software
Foundation; either version 2 of the License, or (at your option) any later
This program is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with
this program; if not, write to the Free Software Foundation, Inc., 675 Mass
Ave, Cambridge, MA 02139, USA.