A method in a communication network comprising a plurality of network controllers and a plurality of mobile nodes served by at least one of the plurality of network controllers is provided. The apparatus can include a first housing including a first housing face, a display coupled to the first housing face, a second housing pivotably attached to the first housing the second housing including a second housing face, the second housing face being configured to cover at least a portion of the first housing face. The intermediate image data generating unit filters an intermediate region in the first image data to generate intermediate second image data. These data patterns are chosen to cause DSV problems.