LinuxQuestions.org
Help answer threads with 0 replies.
Home Forums Tutorials Articles Register
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Software
User Name
Password
Linux - Software This forum is for Software issues.
Having a problem installing a new program? Want to know which application is best for the job? Post your question in this forum.

Notices


Reply
  Search this Thread
Old 09-03-2010, 02:02 AM   #1
fiod
LQ Newbie
 
Registered: Sep 2003
Posts: 26

Rep: Reputation: 15
Virtual Video Device?


Hi,

I am trying desperately to create a virtual video device (v4l2), meaning something like /dev/video0 that when accessing it (say, with xawtv or whatever) I get a certain video file played.

I am trying to do this with vloopback.
After doing modprobe vloopback, the vloopback input device declared is /dev/video0 and the output device is /dev/video1.

I am trying to do this:
Code:
mencoder vid.avi -nosound -vf scale=320:240 -ovc raw -of rawvideo -o /dev/video0
and then to view the movie with this:
Code:
xawtv -c /dev/video1
But the output from xawtv that I am getting is:
Code:
[cv@myhost ~]$ xawtv -c /dev/video1 
This is xawtv-3.95, running on Linux/x86_64 (2.6.34-ARCH)
xinerama 0: 1280x1024+0+0
WARNING: No DGA direct video mode for this display.
can't open /dev/video1: Invalid argument
v4l-conf had some trouble, trying to continue anyway
v4l2: open /dev/video1: Invalid argument
v4l2: open /dev/video1: Invalid argument
v4l: open /dev/video1: Invalid argument
no video grabber device available
The relevant lines from dmesg:
Code:
Linux video capture interface: v2.00
[vloopback_init] : video4linux loopback driver v1.4-trunk
[vloopback_init] : Loopback 0 registered, input: video0, output: video1
[vloopback_init] : Loopback 0 , Using 2 buffers
Does anyone know why this doesn't work?
Anyone knows of a better way to get this working?

Any help will be greatly appreciated...

Thanks a lot
fiod

Last edited by fiod; 09-03-2010 at 02:03 AM.
 
Old 09-04-2010, 11:41 AM   #2
estabroo
Senior Member
 
Registered: Jun 2008
Distribution: debian, ubuntu, sidux
Posts: 1,126
Blog Entries: 2

Rep: Reputation: 124Reputation: 124
are you sure on the /dev/videoN ports? If you have some other v4l device plugged in (like a webcam) then those ports will get shifted.
 
  


Reply



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off



Similar Threads
Thread Thread Starter Forum Replies Last Post
lm-sensors acpitz-virtual-0 Adapter: Virtual device temp1: <- What is it? Maintech Linux - Hardware 9 08-24-2009 02:35 PM
Virtual sound output device? ACiD GRiM Linux - Software 1 07-03-2009 01:58 AM
Wanted capture device for VCR device with Audio and Video outs only k_graham Linux - Newbie 2 06-18-2009 11:24 PM
can I create a virtual device that.... 0xdefec8 Linux - Server 1 08-26-2008 11:08 AM
Need help with shapecfg working with virtual eth device rdmaxx Linux - Networking 1 02-10-2005 04:38 PM

LinuxQuestions.org > Forums > Linux Forums > Linux - Software

All times are GMT -5. The time now is 08:36 PM.

Main Menu
Advertisement
My LQ
Write for LQ
LinuxQuestions.org is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
Syndicate
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Open Source Consulting | Domain Registration