libuvc not setting image size correctly
I am trying use an HD web cam for tracking QR codes, but when I tell libuvc to output a 720X1280 image I get a 640X480 one. here is the launch file code for libuvc
<node pkg="libuvc_camera" type="camera_node" name="logitech_cam">
<param name="vendor" type="string" value="0x046d"/>
<param name="product" type="string" value="0x082d" />
<param name="serial" type="string" value="D016F4DF" />
<param name="image_width" type="int" value="1280"/>
<param name="image_height" type="int" value="720"/>
<param name="pixle_format" type="string" value="mjpeg"/>
<param name="auto_focus" type="bool" value="True" />
</node>
does anyone why it is sending the wrong sized image?