Energy Efficient Vlsi Architectures For Real Time And 3d Video Processing

Energy-Efficient VLSI Architectures for Real-Time and 3D Video Processing

Multiview autostereoscopic displays (MADs) make it possible to view video content in 3D without wearing special glasses, and such displays have recently become available. The main problem of MADs is that they require several (typically 8 or 9) views, while most of the 3D video content is in stereoscopic 3D today. To bridge this content-display gap, the research community started to devise automatic multiview synthesis (MVS) methods. Common MVS methods are based on depth-image-based rendering, where a dense depth map of the scene is used to reproject the image to new viewpoints. Although physically correct, this approach requires accurate depth maps and additional inpainting steps. Our work uses an alternative conversion concept based on image domain warping (IDW) which has been successfully applied to related problems such as aspect ratio retargeting for streaming video, and dispa- rity remapping for depth adjustments in stereoscopic 3D content. IDW shows promising performance in this context as it only requires robust, sparse point- correspondences and no inpainting steps. However, MVS, using IDW as well as alternative approaches, is computationally demanding and requires realtime processing - yet such methods should be portable to end-user and even mobile devices to develop their full potential. To this end, this thesis investigates efficient algorithms and hardware architectures for a variety of subproblems arising in the MVS pipeline.

Energy-Efficient VLSI Architectures for Real-Time and 3D Video Processing

An Event-Driven Parallel-Processing Subsystem for Energy-Efficient Mobile Medical Instrumentation

Aging population and the thereby ever-rising cost of health services call for novel and innovative solutions for providing medical care and services. So far, medical care is primarily provided in the form of time-consuming in-person appointments with trained personnel and expensive, stationary instrumentation equipment. As for many current and past challenges, the advances in microelectronics are a crucial enabler and offer a plethora of opportunities. With key building blocks such as sensing, processing, and communication systems and circuits getting smaller, cheaper, and more energy-efficient, personal and wearable or even implantable point-of-care devices with medicalgrade instrumentation capabilities become feasible. Device size and battery lifetime are paramount for the realization of such devices. Besides integrating the required functionality into as few individual microelectronic components as possible, the energy efficiency of such is crucial to reduce battery size, usually being the dominant contributor to overall device size. In this thesis, we present two major contributions to achieve the discussed goals in the context of miniaturized medical instrumentation: First, we present a synchronization solution for embedded, parallel near-threshold computing (NTC), a promising concept for enabling the required processing capabilities with an energy efficiency that is suitable for highly mobile devices with very limited battery capacity. Our proposed solution aims at increasing energy efficiency and performance for parallel NTC clusters by maximizing the effective utilization of the available cores under parallel workloads. We describe a hardware unit that enables fine-grain parallelization by greatly optimizing and accelerating core-to-core synchronization and communication and analyze the impact of those mechanisms on the overall performance and energy efficiency of an eight-core cluster. With a range of digital signal processing (DSP) applications typical for the targeted systems, the proposed hardware unit improves performance by up to 92% and 23% on average and energy efficiency by up to 98% and 39% on average. In the second part, we present a MCU processing and control subsystem (MPCS) for the integration into VivoSoC, a highly versatile single-chip solution for mobile medical instrumentation. In addition to the MPCS, it includes a multitude of analog front-ends (AFEs) and a multi-channel power management IC (PMIC) for voltage conversion. ...