Re: video4linux - wine

[luis lenders]

MediaHost (TM) wrote:
> > However, is there any development going on

concerning v4l and/or USB?
> > Actually it's a pity, that I couldn't realize this

project....we would
> > have been willing to invest in such code....
> I'm not sure what the capabilities of video4linux

are, >which devices it
> supports or how its API works.  I know it supports at
> least some USB webcams.

Actually video4linux has quite some capabilities, a
program like xawtv for example can even grab a movie
from your tv-tuner card.
> > As we can access /dev/usb/lpt or /dev/dsp, it

should >>be possible to access /dev/video....I'm not
familiar >>in implementing such stuff at  wine,
but....?

Altough I'm a programming noob i tried a few weeks ago
 to write some code to accomplish this with (not much)
but still a little succes: i used code from a program
like vidcat to read a frame from my v4l device (in png
format), used code from another program (png2bmp) to
turn it into a bitmap, and used CreateWindowEx to
display this in a windowsprogram under wine. Although
the window with the frame from my webcam showed up ,
the windowsprogram did not behave further as it should
do. There is plenty of code to be found on the
internet 
using the v4l api, but the problem  how to get this in
wine. Maybe someone has some further hints? 
Regards luis

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video4linux - wine

[Rick Romero]

On Wed, 2005-01-05 at 08:17, luis lenders wrote:
> MediaHost (TM) wrote:
> > > However, is there any development going on
>
> concerning v4l and/or USB?
> > > Actually it's a pity, that I couldn't realize this
>
> project....we would
> > > have been willing to invest in such code....
> > I'm not sure what the capabilities of video4linux
>
> are, >which devices it
> > supports or how its API works.  I know it supports at
> > least some USB webcams.
>
> Actually video4linux has quite some capabilities, a
> program like xawtv for example can even grab a movie
> from your tv-tuner card.
> > > As we can access /dev/usb/lpt or /dev/dsp, it
>
> should >>be possible to access /dev/video....I'm not
> familiar >>in implementing such stuff at  wine,
> but....?
>
> Altough I'm a programming noob i tried a few weeks ago
>  to write some code to accomplish this with (not much)
> but still a little succes: i used code from a program
> like vidcat to read a frame from my v4l device (in png
> format), used code from another program (png2bmp) to
> turn it into a bitmap, and used CreateWindowEx to
> display this in a windowsprogram under wine. Although
> the window with the frame from my webcam showed up ,
> the windowsprogram did not behave further as it should
> do. There is plenty of code to be found on the
> internet 
> using the v4l api, but the problem  how to get this in
> wine. Maybe someone has some further hints?

I don't consider myself a programmer, so I'm probably the last person to
comment on this, BUT...

I did some work with motion.sourceforget.net, and in playing with v4l,
and v4l2 (and creating a 'multiout' - sending multiple channels on one
device to multiple video devices), I can tell you that just opening the
/dev/video (or v4l2 - /dev/v4l/video, IIRC) will just get you a plain
YUV stream.  It's pretty easy to manipulate at that point.  The 'trick'
to v4l is v4l support for your device.  Once you have that support,
there are a million things you can do with it.

vgrabber is a really simple frame grabber if you're looking for more
info on how v4l works:
http://www.tazenda.demon.co.uk/phil/v4l.html

I dare say, if Windows is expecting a YUV stream from it's image capture
device, it might be just enough to fake a Windows device that's just
reads from /dev/video

Unfortunately I don't know anything about Video for Windows.

HTH

Rick
> Regards luis
>
> ___________________________________________________________ 
> ALL-NEW Yahoo! Messenger - all new features - even more fun! http://uk.messenger.yahoo.com

video4linux - wine

[MediaHost (TM)]

What you write here, seams to me very interesting! Specially your last 
sentence is actually the thing I'm looking for: How to make win 
applications believe, that there is a real device and supply whatever it 
wants....

So even the project I was supposed to work on, is already dead, before 
it started really, but I think there is a interesting discussion going 
on.....so maybe we keep it going? Support for web cams under wine! 
Sounds terrific!

Of course v4l support is the basic condition, but there are many (linux) 
drivers around for web cams. I think, that there are programmers on this 
list, which have the expertise to get us one step further with 
implementing a video device under wine. It's probably the same approach, 
like implementing /dev/dsp oss or alsa driver settings, but for the 
video stream!?

Rick Romero wrote:
> On Wed, 2005-01-05 at 08:17, luis lenders wrote:
> > MediaHost (TM) wrote:
> > > > However, is there any development going on
> >
> > concerning v4l and/or USB?
> > > > Actually it's a pity, that I couldn't realize this
> >
> > project....we would
> > > > have been willing to invest in such code....
> > >
> > > I'm not sure what the capabilities of video4linux
> >
> > are, >which devices it
> > > supports or how its API works.  I know it supports at
> > > least some USB webcams.
> >
> > Actually video4linux has quite some capabilities, a
> > program like xawtv for example can even grab a movie
> > from your tv-tuner card.
> > > > As we can access /dev/usb/lpt or /dev/dsp, it
> >
> > should >>be possible to access /dev/video....I'm not
> > familiar >>in implementing such stuff at  wine,
> > but....?
> >
> > Altough I'm a programming noob i tried a few weeks ago
> > to write some code to accomplish this with (not much)
> > but still a little succes: i used code from a program
> > like vidcat to read a frame from my v4l device (in png
> > format), used code from another program (png2bmp) to
> > turn it into a bitmap, and used CreateWindowEx to
> > display this in a windowsprogram under wine. Although
> > the window with the frame from my webcam showed up ,
> > the windowsprogram did not behave further as it should
> > do. There is plenty of code to be found on the
> > internet 
> > using the v4l api, but the problem  how to get this in
> > wine. Maybe someone has some further hints?
>
> I don't consider myself a programmer, so I'm probably the last person to
> comment on this, BUT...
>
> I did some work with motion.sourceforget.net, and in playing with v4l,
> and v4l2 (and creating a 'multiout' - sending multiple channels on one
> device to multiple video devices), I can tell you that just opening the
> /dev/video (or v4l2 - /dev/v4l/video, IIRC) will just get you a plain
> YUV stream.  It's pretty easy to manipulate at that point.  The 'trick'
> to v4l is v4l support for your device.  Once you have that support,
> there are a million things you can do with it.
>
> vgrabber is a really simple frame grabber if you're looking for more
> info on how v4l works:
> http://www.tazenda.demon.co.uk/phil/v4l.html
>
> I dare say, if Windows is expecting a YUV stream from it's image capture
> device, it might be just enough to fake a Windows device that's just
> reads from /dev/video
>
> Unfortunately I don't know anything about Video for Windows.
>
> HTH
>
> Rick
> > Regards luis
> >
> > ___________________________________________________________ 
> > ALL-NEW Yahoo! Messenger - all new features - even more fun! http://uk.messenger.yahoo.com