[AG-TECH] more on multi-input capture.

Derek Piper dcpiper at indiana.edu
Wed Jul 13 14:15:37 CDT 2005

	No, I explained how that part works my previous post. Maybe a diagram 
would be good.

VIC -> 'Microsoft WDM Image Capture' -> Source0
VIC -> 'Microsoft WDM Image Capture' -> Source1
VIC -> 'Microsoft WDM Image Capture' -> Source2
VIC -> 'Microsoft WDM Image Capture' -> Source3

	VIC only binds to 'Microsoft WDM Image Capture', *it doesn't know about 
the sources beyond that*. Upon invocation, the WDM driver will choose 
the first 'source' it can find, since none was given. This leads to all 
four VICs choosing Source0 (probably) and 3 of them will not be able to 
get it and will complain by putting up a selector box to choose another 
source. So, you go ahead and choose another source, i.e. Source1 for the 
first one you have to alter, then Source2 for the other one etc. All 4 
VICs will then be up and running. Unfortunately you will need to do this 
EVERY TIME you change venues. If it drives you crazy, use a Linux box 
for video from multiple sources.


Fred Dech wrote:
> Derek.
> how are you able to see all 4 sources if only one shows up as an option
> when you are adding a VideoService in the AG NodeManagement tool?
> you set up 4 VideoProducerServices with the single source
> that is available to you and then you are able to see all four sources
> from the Video Sources Settings submenu of each Vic menu??
> --fred
> On Wed, Jul 13, 2005 at 09:46AM, Derek Piper said:
>>	To clarify this, you can still use all four inputs for an AG session 
>>	- you just need to have 4 instances of VIC
>>	Derek
>>Thomas D. Uram wrote:
>>>There is a vfw/wdm mapper, but it can only map a single wdm device to vfw, 
>>>so vic only has
>>>access to one of the four.
>>>On 07/13/05 08:20, Derek Piper wrote:
>>>>  I believe there is a 'wrapper' in 2000/XP for WDM drivers to the VfW
>>>>interface that VIC uses.
>>>>  Derek
>>>>Fred Dech wrote:
>>>>>thanks, Derek.
>>>>>but what i don't understand is this.
>>>>>if the Spectra8 currently uses WDM drivers in Windows...
>>>>>VIC relies on VFW type drivers.  that's what the problem is/was with the
>>>>>newer WDM driver Winnov Videum cards and VIC.
>>>>>i'm missing something.
>>>>>On Tue, Jul 12, 2005 at 04:38PM, Derek Piper said:
>>>>>>  Hi,
>>>>>>  Having installed a Spectra8 after using a WinTV 150PVR, I can
>>>>>>tell     you it's *very easy* to get going. Yes, each input installs
>>>>>>a driver individually (4 goes round the 'found new hardware' wizard -
>>>>>>yawn, but once it's done it's done). After that it just works like 4
>>>>>>individual capture cards. As mentioned before, the inherent problem
>>>>>>with VIC not being able to differentiate between the sources and
>>>>>>'colliding' over what input to use still remains, but that's Windows
>>>>>>thing and happens any time there is more than one capture device. You
>>>>>>just have to select the 'other' source(s), whatever they may be, when
>>>>>>the window prompts you and all sources will come up nicely.
>>>>>>  Spectra8 cards, being 4 BT878 chips, would work nicely under
>>>>>>Linux     and not suffer from that problem (they'd just be
>>>>>>/dev/video0, /dev/video1 etc.), although I have not personally tested
>>>>>>  Derek
>>>>>>Fred Dech wrote:
>>>>>>>this has been covered in various ways at various times.  but i've got
>>>>>>>a new question on this subject.
>>>>>>>we had a problem with the last Winnov Videum card we spec'd for another
>>>>>>>institution because before they purchased the card the Videum been
>>>>>>>to WDM drivers.  while the VFW drivers would make it work right for
>>>>>>>AG, this
>>>>>>>other institution needed to use the software that came with the
>>>>>>>capture card.
>>>>>>>i've noticed quite a few posts by people successfully using the
>>>>>>>4 input card.  so i've now come to the point of replacing that Winnov
>>>>>>>Videum with something that will cover all the needs of our
>>>>>>>proprietary capture software and AG.
>>>>>>>i'm looking at a web page with Spectra8 specifications.  i'm very, very
>>>>>>>surprised to see, "... each frame grabber channel has it's own WDM
>>>>>>>allowing you to capture from 4 individual video channels."
>>>>>>>now i'm really confused.  is the WDM driver relatively recent for the
>>>>>>>Spectra8?  it must be... or how have people made it work well with
>>>>>>>any insights would be greatly appreciated.
>>>>>>Derek Piper - dcpiper at indiana.edu - (812) 856 0111
>>>>>>IRI 323, School of Informatics
>>>>>>Indiana University, Bloomington, Indiana
>>Derek Piper - dcpiper at indiana.edu - (812) 856 0111
>>IRI 323, School of Informatics
>>Indiana University, Bloomington, Indiana

Derek Piper - dcpiper at indiana.edu - (812) 856 0111
IRI 323, School of Informatics
Indiana University, Bloomington, Indiana

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