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The wide application of FMEA in reliability engineering is generally appreciated, and how to identify the failure modes is the key to it. Failure modes, however, rely only on specific components rather than the system architecture, and therefore could be reused in different FMEAs. A novel ontology-based method, to recognize and reuse specific failure modes in existing databases, is provided here, and a light weight tool is developed for this method. The method and the tool can also be used in other fields with similar scenarios.
Software FMEA is valuable and practically used for embedded software of safety-critical systems. In this paper, a novel method for Software FMEA is presented based on co-analysis of system model and software model. The method is hopeful to detect quantitative and dynamic effects by a targeted software failure. A typical application of the method is provided to illustrate the procedure and the applicable scenarios. In addition, a pattern is refined from the application for further reuse.
One Super Hi-Vision (SHV) 4k4k@60 fps fractional motion estimation (FME) engine is proposed in our paper. Firstly, two complexity reduction schemes are proposed in the algorithm level. By analyzing the integer motion cost of sub blocks in each inter mode, the mode reduction based mode pre-filtering scheme can achieve 48% clock cycle saving compared with previous algorithm. By further check the motion cost of search points around best integer candidate, the motion cost oriented directional one-pass scheme can provide 50% clock cycle saving and 36% reduction in the number of processing units (PU). Secondly, in the hardware level, two parallel improved schemes namely 16-Pel processing and MB-parallel scheme are given out in our paper, which reduces design effort to only 145 MHz for SHV FME processing. Also, quarter sub-sampling is adopted in our design and 75% hardware cost is reduced for each PU. Thirdly, one unified pixel block loading scheme is proposed. About 28.67% to 86.39% pixels are reused and the related memory access is saved. Furthermore, we also give out one parity pixel organization scheme to solve memory access conflict of MB-parallel scheme. By using TSMC 0.18 µm technology in worst work conditions (1.62 V, 125), our FME engine can achieve real-time processing for SHV 4k4k@60 fps with 412k gates hardware.
Ming SHAO Zhenyu LIU Satoshi GOTO Takeshi IKENAGA
Fractional Motion Estimation (FME) is an advanced feature adopted in H.264/AVC video compression standard with quarter-pixel accuracy. Although FME could gain considerably higher encoding efficiency, sub-pixel interpolation and sum of absolute transformed difference (SATD) computation, as main parts of FME, increase the computation complexity a lot. To reduce the complexity of FME, this paper proposes a full computation reusable VLSI oriented algorithm. Through exploiting the similarity among motion vectors (MVs) of partitions in the same macroblock (MB), temporary computation results can be fully reused. Furthermore, a simple and effective searching method is adopted to make the proposed method more suitable for VLSI implementation. Experiment results show that up to 80% add operations and 85% internal reference frame memory access operations are saved without any degradation in the coding quality.