To satisfy the Nyquist criteria for image resolution, each pixel of the image shown on the LCD should be sampled by 2 or more pixels in the camera [12]. The image sensor uses limited number of bits per channel for conversion of each color pixel, resulting into quantization noise. To limit the effect of this noise on the overall detection performance it should be maintained 6-10dB below system noise level [13], which on the other hand must be maintained well below signal power level, depending on the modulation method used, in order to have acceptable bit error rates (BER) [14].