Content-dependent block noise reduction for mobile displays
Ga-Hee Kim, Yoon-Gyoo Lee, Han-Eol Kim, Choon-Woo Kim · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 2011
Number of pixels on mobile displays is rapidly increasing. Recently, mobile displays with more than one million pixels have been introduced into markets. However, most of multimedia contents to be displayed on mobile displays have much smaller pixel counts. For example, number of pixels for a T-DMB(terrestrial digital multimedia broadcasting) sequence is 320x240. When enlargement is applied to input sequence, perceived image quality would be degraded. Increase in visibility of block noise is one of the major reasons for image quality degradation on mobile displays. This paper presents a simple and computationally efficient method to reduce visibility of block noise on enlarged multimedia sequences. In proposed method, a simple low pass filtering is selectively applied to the pixels of block noises for reduction of block noise visibility as well as faithful reproduction of image details.