Connection error for linux webcam driver for matlab

Question

This might seem like a duplicate post, well yes it is, but I have a different problem compared with the duplicate version of it.

My value for imaqhwinfo gives me:

   InstalledAdaptors: {'dcam'  'linuxvideo'}
    MATLABVersion: '7.14 (R2012a)'
      ToolboxName: 'Image Acquisition Toolbox'
   ToolboxVersion: '4.3 (R2012a)'

The value for imaqhwinfo('linuxvideo',1) gives me:

DefaultFormat: 'YUYV_640x480'
   DeviceFileSupported: 0
            DeviceName: '1.3M WebCam'
              DeviceID: 1
 VideoInputConstructor: 'videoinput('linuxvideo', 1)'
VideoDeviceConstructor: 'imaq.VideoDevice('linuxvideo', 1)'
      SupportedFormats: {1x7 cell}

So, after that I gave the following to the Matlab terminal:

vid = videoinput('linuxvideo', 1);
set(vid, 'ReturnedColorSpace', 'RGB');

However, after inputting the following line:

img = getsnapshot(vid);

I get the following error:

Warning: Unable to set the selected source.  Perhaps the device is in use. 
Error using imaqdevice/getsnapshot (line 62)
Could not connect to the image acquisition device.  Device may be in use.

I posted this question to Matlab central and am waiting for a reply.

I'm using ArchLinux(64 bit) & Matlab(2012a) ( 64 bit). Webcam apps such as Cheese are running okay. I can see my face. I also have Skype, though I haven't configured it yet.

TL;DR

Can anybody help me fix this issue? It would be a great help, because if I cannot, I'll have to re-install Windows 7 for just a little bit of a school assignment, and that's time consuming. Plus I don't want to go back to Windows right now.

P.S: lsusb gives me:

Bus 002 Device 005: ID 148e:099a EVATRONIX SA 
Bus 002 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 003: ID 064e:a219 Suyin Corp. 1.3M WebCam (notebook emachines E730, Acer sub-brand)
Bus 001 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

Answer 1

How about if you include the image size argument?

vid = videoinput(‘linuxvideo’, 1, ‘YUYV_640x480′);

Then try opening a preview window to view video at runtime:

preview(vid);

Formats

Also you can find out the acceptable formats:

info = imaqhwinfo('linuxvideo', 1);
info.SupportedFormats'

These formats can be used thusly:

vid = videoinput(‘linuxvideo’, 1, ‘...formats here...′);

Additional things to try?

I'd take a look at this ArchLinux forums thread titled: [SOLVED] matlab image capturing using webcam. There were several other things to try if the above doesn't work out.