Video Screen capture

  • Thread starter Thread starter Robert
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Robert

Does anyone know if there is a way to capture the
onscreen content of a PC through the video outputs? I
have a Laptop with both S-Video and RCA video out jacks.
I would like to capture the onscreen content from a PC
while performing tasks. I have tried the capture in MM2,
Ulead VideoStudio 7 and Pinnacle Studio 8 without
success. It does appear there is a signal, as I get a
small green block in the capture. Are there certain
resolution limits or is the capture device not configured
properly? I am using a Radeon All In Wonder 9000.
Thanks for any help!
 
Hi there,

Short answer : with out additional software equipment No.

When you say that there is a "It does appear there is a signal" exactly what
have you done to get that signal.

To a very large extent the type of video card you have, certainly in this
context, is irrelevant.

Programs that capture video/audio capture it from a device. The device presents
itself to windows XP and identifies its capabilities. If the device has the
ability to send out from itself a video signal it will tell windows what depth
of colour it has along with frame rate, synchronization method etc etc. Similar
data is given to windows about any audio feed that it may be capable of
producing.

Windows through a common user interface presents this information to the
program that is going to perform the capture...thats why if you have a USB only
device, you will not get the ability to capture DV-AVI (That's not 100% true
some devices actually claim to have abilities they do not posses)

I suppose if you had two graphics cards and video out from one was sent to
video in on the other you might start to get somewhere. BUT you would need a
computer with a very high Front-End Bus Speed because both video cards would be
pumping data along it...this would probably mean that best images would only be
available at low resolution and or frame speed.

There is a codes from Microsoft with a name implying it is for use during
screen capture. I have seen it on my system but paid little notice of it. You
may want to see if it exists on your machine and determine how it can be used
 
John,

Thanks for the response!

I believe I need to clarify...Here's the specifics of
what I am trying to do:

I have a Dell workstation (with plenty of processing
power!) with the ATI All-in-Wonder. I want to use the
Dell system to capture analog video from a Compaq
workstation using either the S-video or composite video
output on the Compaq. It is my understanding that the s-
video/composite outputs on the Compaq will display
desktop output directly on to a TV monitor (something I
have done before with a different computer).

I currently have the Compaq s-video out plugged into the
ATI's S-video input box. The capture runs for a few
seconds and says it's corrupted, which is obvious by the
preview. I have adjusted the Compaq's desktop display
resolution down as far as possible and set the properties
to extend the desktop on to a TV monitor with zero
positive results.

As an experiment, I brought my Olympus digital camera in
and hooked it up using the TV cord (the cord that allows
you to display pictures on a TV) and get the similar
results. This leads me to believe there is a problem
with how the ATI card is interpreting the signal it
receives.

All three programs I spoke of (Ulead Studio 7, MM2 and
Pinnacle Studio 8) give very similar results. All three
programs recognize the capture card and appear to receive
some kind of signal, just not one that is recognizable.

Does this info help? Am I missing something completely
obvious? Am I taking something for granted? Thanks
again for helping us all out!

robert
 
Hi there,

Yes I mis-understood your original question...I thought you were trying to do
the whole thing with one machine.

I am not sure what to tell you to do to be quite honest. I certainly agree that
there seems to be an output problem from the one card..I have not bothered to
look and see where in the world you are but here are a few thoughts.

In the UK there are 625 lines on a TV screen and by over scanning them (from
the RF signal) you get the picture with some loss at the top and bottom. BUT
the video out socket is 350 lines (I think) and S-VHS video out is 400 lines
(That's why a copied TV picture is never quite as good as the original)

Two visits ago to the USA I found a video camera at a silly price in Comp USA.
The salesman could not tell me if it would interface with equipment here in the
UK so I phoned a friend of mine in the video business, his answer was
definitely not....Video Out in the UK is not compatible with video out in the
USA.

So where did you buy these cards???? are you certain they are both for your
market?

If that idea fails, are they both S-VHS or both VHS. I would have said have a
look at the socket on the cards...but my vivo card which is S-VHS, has a
non-standard plug which at first glance looks like a S-VHS connector....it has
many more pins than normal.

And finally going down as basic as I can....are you sure you have them
connected the right way down...Sorry if that offends but I did say it was basic
:)

If that thought fails to help then I am stuck

I have to shoot off just now...so I will look to see if there are any further
comments tomorrow afternoon........Have Fun
 
Robert,

Are you using the ATI Input/ Output adapters that came with your AIW cards?
Unless something has changed with the later 8/ 9xxx series cards, you must
use the inclusive ATI Adapters because the S-Video pin configurations are
proprietary.
 
John and Digger,

Thanks again for your continued support! In response to
Digger,
I am using the ATI supplied dongle connectors with
regular RCA and s-video cables to make the link between
the machine and the dongle.

I have some new developments...

Following some information I found on PapaJohn's website,
I reinstalled the AIW software and discovered that the
ATI multimedia center did not install properly the first
time around. After following Papa's instructions, I now
have a semi-functional screen capture. I can capture
analog video without a problem! I am still having
difficulty with the "desktop capture" however.

I have a good signal as I can see the background of the
connected computer when I try to capture....however,
nothing on the desktop appears! There aren't any icons,
windows, taskbar, etc...just the background. Is there a
setting I am missing somewhere?

Thanks again for your help!

robert
 
Don't know what display settings are currently being used, but you might
want to try playing with display settings on the sending machine; 800x600 or
even 640x480.
 
Digger,

Yeah, I gave that a try but ot no avail. I plan to bring
one of the machines home and connect it to a TV to see
what I get.
 
I have solved my problem! I must say it was something I
never suspected! As it turns out, the outputs on the
back of the laptop work exactly the way they should.
However, the outputs on the back of the docking station
DON'T. It is very strange as they are exactly the same
type of connection (composite video and s-video) but for
some reason the signal gets changed. I was only
receiving the desktop background through the port
replicator whereas through the laptop outputs I would
receive the full signal with all the "action" ON the
desktop.

Thanks everyone for your help!
 
Robert said:
Does anyone know if there is a way to capture the
onscreen content of a PC through the video outputs?
Click to expand...

I know you got it working in the end, but unless you have a specific reason
to do it like that, why not just capture the screen using the free Windows
Media Encoder? You end up with an optimised wmv file, the quality of which
is your choosing vs filesize. I've used it a couple of times to send a mini
"how to" movie to people who just simply can't follow instructions! Easier
to look at an example.
 
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