Is WebcamTexture the same resolution as GUITexture?

I've followed the examples of using a WebCamTexture to stream my webcam to a Rectangular Game Object.

I'm also using GUI.Box to highlight areas of the WebCamTexture that I'd like to process in OpenCV.

However, it seems like the pixel coordinates of the WebCamTexture are slightly different than the pixel coordinates of the GUI box.

Is there a way to make the resolution of the GUI texture the same as the WebCamTexture?

Thanks.
-Tony