Gerben Johan Hekstra

Content based contrast enhancement for liquid crystal displays with backlight modulation

One of the major problems plaguing liquid crystal displays (LCDs) is the light leakage at low grey levels. This undesirable effect degrades the ability of these displays to discern and display dark scenes accurately. In this paper, we propose an architecture that will largely eliminate this undesirable effect through backlight modulation. Other benefits of backlight modulation will also be outlined and the results shown.

TriMedia CPU64 design space exploration

Within Philips Research Labs, we are investigating the 64-bit VLIW core for future TriMedia processors. We have performed an extensive design space exploration (DSE) on this core using quantitative analysis, using a benchmark suite of applications which are representative for multimedia processing. We have explored, among others, the configurations of the different functional units (FUs) of the 64-bit VLIW core. We show the merit of our approach and of the environment that we have developed for design space exploration.

TriMedia CPU64 application domain and benchmark suite

At Philips Research Labs, we are investigating the 64-bit VLIW core (also called CPU64) for future TriMedia processors. This processor is targeted towards embedded multimedia applications. In order to be able to perform a quantitative design space exploration, a set of benchmark applications has been developed which is representative of the application domain. This article describes the way the benchmark set was developed as well as providing a more detailed description of one of the benchmarks. As a result, it is shown that this new CPU has a high performance for the application domain while the programming interface is very convenient. Furthermore, such a programmable media processor may offer new options and challenges to algorithm designers.

25.3: Spectrum Sequential Liquid Crystal Display

Conventional displays cannot show all real-world colours. We have made a 30-inch Spectrum Sequential LCD that uses two different types of fluorescent lamps that alternately illuminate the panel. In this way, a 6 primary display is obtained with a 22% larger colour gamut, without modifying the panel itself.

48.3: LCD Overdrive Frame Memory Reduction using Scalable DCT-based Compression

Using a scalable DCT-based compression method of low hardware complexity we have reduced the size of the memory that is required for LCD overdrive. Compression ratios up to 16 do not lead to a noticeable loss of sharpness or artifacts. Due to the application of a novel technique this holds also for still images.

Evaluation of Fast Rotation Methods

In this paper, we present a comprehensive inventory and evaluation of fast rotation methods. Fast rotations are arithmetic methods for performing orthonormal rotation at a very low cost in implementation. We show that there are different implementation forms for fast rotations, and propose a classification for them. We compare fast rotation methods with a direct form and with a factored form implementation, and examine the trade-offs that existbetween the angle of rotation, the accuracy in scaling, and the cost of performing the rotation.