Using two webcam for uvc_camera stereo_node

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Hi,

In all I have three camera. two external webcam and 1 integrated webcam on laptop.

When I run the command $rosrun uvc_camera stereo_node

using the integrated webcam and either of the external webcam everything works fine and I get required topics published.

I am facing difficulty get the two external webcam running together. The node would crash. I get the following error at the end

unable to set control: Invalid argument

ERROR: could not set some settings.  
 unable to set control 
terminate called after throwing an instance of 'std::runtime_error'
  what():  unable to start capture
/opt/ros/cturtle/ros/bin/rosrun: line 35:  5770 Aborted                 $exepath "$@"

The complete message

root@robot-laptop:/opt/ros/cturtle/ros# rosrun uvc_camera stereo_node  _left/device:="/dev/video0" _right/device:="/dev/video1" _width=320 _height=240
opening /dev/video0
pixfmt 0 = 'YUYV' desc = 'YUV 4:2:2 (YUYV)'
  discrete: 640x480:   1/30 1/15 1/10 1/5 
  discrete: 352x288:   1/30 1/15 1/10 1/5 
  discrete: 320x240:   1/30 1/15 1/10 1/5 
  discrete: 176x144:   1/30 1/15 1/10 1/5 
  discrete: 160x120:   1/30 1/15 1/10 1/5 
  int (Brightness, 0, id = 980900): 0 to 255 (1)
  int (Contrast, 0, id = 980901): 0 to 255 (1)
  int (Saturation, 0, id = 980902): 0 to 255 (1)
  int (Hue, 0, id = 980903): -128 to 127 (1)
  int (Gamma, 0, id = 980910): 1 to 16 (1)
  int (Gain, 0, id = 980913): 0 to 65535 (1)
  menu (Power Line Frequency, 0, id = 980918): 0 to 2 (1)
    0: Disabled
    1: 50 Hz
    2: 60 Hz
  int (Sharpness, 0, id = 98091b): 1 to 64 (1)
  int (Backlight Compensation, 0, id = 98091c): 1 to 16 (1)
  menu (Exposure, Auto, 0, id = 9a0901): 0 to 3 (1)
    0: Auto Mode
    1: Manual Mode
    2: Shutter Priority Mode
    3: Aperture Priority Mode
  int (Exposure (Absolute), 0, id = 9a0902): 1 to 1001 (1)
unable to set control: Invalid argument
ERROR: could not set some settings.  
 unable to set control 
opening /dev/video1
pixfmt 0 = 'YUYV' desc = 'YUV 4:2:2 (YUYV)'
  discrete: 640x480:   1/30 1/15 1/10 1/5 
  discrete: 352x288:   1/30 1/15 1/10 1/5 
  discrete: 320x240:   1/30 1/15 1/10 1/5 
  discrete: 176x144:   1/30 1/15 1/10 1/5 
  discrete: 160x120:   1/30 1/15 1/10 1/5 
  int (Brightness, 0, id = 980900): 0 to 255 (1)
  int (Contrast, 0, id = 980901): 0 to 255 (1)
  int (Saturation, 0, id = 980902): 0 to 255 (1)
  int (Hue, 0, id = 980903): -128 to 127 (1)
  int (Gamma, 0, id = 980910): 1 to 16 (1)
  int (Gain, 0, id = 980913): 0 to 65535 (1)
  menu (Power Line Frequency, 0, id = 980918): 0 to 2 (1)
    0: Disabled
    1: 50 Hz
    2: 60 Hz
  int (Sharpness, 0, id = 98091b): 1 to 64 (1)
  int (Backlight Compensation, 0, id = 98091c): 1 to 16 (1)
  menu (Exposure, Auto, 0, id = 9a0901): 0 to 3 (1)
    0 ...