Virtual video device

Hi guys / girls(who knows)
It's a bit off the strict "archlinux" subject, but I have a technical challenge that I'd like to share with other experienced linux users / developers.
Here's the context : I'd like to implement some kind of virtual video device, that I could feed with some data (typically a feed from a "real" camera, post processed and mixed with other information, for video chat use). I'v googled around for existing implementations, and found the following :
* http://www.lavrsen.dk/foswiki/bin/view/ … backDevice
* http://v4l.videotechnology.com/vivi.html
* http://v4l2vd.sourceforge.net/
but unfortunately all of these solutions require kernel-space intervention. I ideally would like to remain exclusively on the user-space side, for ease of redistribution and maintenance. I think there's also a possibility using gstreamer, that has a v4lsink element I think, but gstreamer is not something I'm very familiar with.
Anyone of you having any ideas how I could do that? I will seriously start looking in-depth at the V4L2 API, but any lead to narrow down my researches would be welcome.
Thanks in advance,

Hi,
At one time this was Bundled on Some Macs
http://www.ambrosiasw.com/utilities/snapzprox/
It will let you capture a segment of your Screen with or without Audio
8:07 PM Sunday; March 9, 2008

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Virtual video capture device driver for screencapture available ?

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Hi,
At one time this was Bundled on Some Macs
http://www.ambrosiasw.com/utilities/snapzprox/
It will let you capture a segment of your Screen with or without Audio
8:07 PM Sunday; March 9, 2008

Virtual Capture Device integration

Hello,
I want to encode and send to a FMS server for streaming over
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This is a sample (frame: rendering time)
1: 2
2: 2
3: 4
4: 2
5: 2
6: 24
7: 2
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9: 89
10: 88
11: 98
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I have searched many places online and in this forum for similar questions. A few I have found could be outdated or might not apply in this case.
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https://social.technet.microsoft.com/Forums/en-US/09f3de07-20de-4328-970a-53ee1f3e74b1/vgpu-and-remotefx-in-ubuntu-vm-on-windows-server-2012?forum=linuxintegrationservices
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https://social.technet.microsoft.com/Forums/en-US/0c2b4ba8-ff71-4379-990e-046c7ca76cfc/this-is-quite-interesting?forum=linuxintegrationservices
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http://ubuntuforums.org/showthread.php?t=2204843
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Thanks for your time,
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Michael Kelley, Lead Program Manager, Open Source Technology Center

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-L

nopenshaw3 wrote:
I have searched through the forums relentlessly of both Mac and third party, but I seem to never find a good, well thought out answer for my specific question. Every answer is filled with snobby know-it-alls who either respond with sarcastic answers or post links to other threads that don't answer the question in an attempt to make the asker feel like an idiot.
Not the best way to get started frankly but ...
nopenshaw3 wrote:
QUESTION 1: Is there anyway that I can buy a new logic board with upgraded graphics card and it will work?
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nopenshaw3 wrote:
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Maybe, if the Sonnet is properly Thunderbolt compatible it should.
nopenshaw3 wrote:
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At the Apple Icon at top left>About this Mac.
Then click on More Info>Hardware>Graphics/Displays and report like this...
NVIDIA GeForce 7800GT:
Chipset Model:          GeForce 7800GT
Type:          Display
Bus:          PCI
Slot:          SLOT-1
VRAM (Total):          256 MB
Vendor:          nVIDIA (0x10de)
Device ID:          0x0092
Revision ID:          0x00a1
ROM Revision:          2152.2
Displays:
VGA Display:
Resolution:          1920 x 1080 @ 60 Hz
Depth:          32-bit Color
Core Image:          Supported
Main Display:          Yes
Mirror:          Off
Online:          Yes
Quartz Extreme:          Supported
Display:
Status:          No display connected
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The combo update for PowerPC-based Macs...
http://www.apple.com/support/downloads/macosx10411comboupdateppc.html

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not sure what you are trying to achieve...
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Failed to open video device /dev/video0: No such file or directory
Could not fetch initial image from camera
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system: arch arm
user is in video group
output of lsusb:
$lsusb
Bus 001 Device 002: ID 0424:9512 Standard Microsystems Corp. LAN9500 Ethernet 10/100 Adapter
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 003: ID 0424:ec00 Standard Microsystems Corp.
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# for FreeBSD default is /dev/bktr0
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ls /dev before running motion:
ls /dev | grep video
video0
ls /dev after running motion in daemon mode (still running):
ls /dev | grep video
video1
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That was the only tidbit I could find online regarding the issue. I have had motion set up with this camera before, but it was on a different machine running x86_64 arch.
thanks
SOLUTION
I wasn't thinking about the draw for the camera and was trying to just have it powered through the usb on a raspberry pi (need a powered usb hub). I am not sure however why the device file switches when there is not enough power, so if you come across this an know please post a reply.
Last edited by brewforce (2013-01-31 03:05:08)

andre.ramaciotti wrote:And I'm not sure if you should put that & after exec awesome. It works fine here without it.
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Darren

But I am getting this alert from SCOM and SCOM has no information about the alert for me to find out what to do - thought that was the point of SCOM to let you know of problems and how to resolve them. :)
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Thanks for responding.
Time Sampled:
09/02/2013 14:08:48
Object Name:
Hyper-V Virtual Storage Device
Counter Name:
Error Count
Instance Name:
c:-clusterstorage-volume1-myvm-virtual
hard disks-MyVM-DATA02.vhdx
Value:
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Darren

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