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3D shape information is one of the very important clues in image processing and computer vision. Unlike traditional multi-input depth from defocus (DFD) technique, monocular DFD (MDFD) algorithm proposed by Hu and Haan can reconstruct 3D shape only from a single monocular defocus image with low computing complexity. In this paper, we present a real-time MDFD system implemented on the FPGA device. In order to reduce the FPGA design cost, vivado high level synthesis (VHLS) is applied to design the MDFD system. The system architecture on the basis of FIFO based convolution is first designed through C/C++ code that is further converted to the FPGA design by VHLS. Then the PIPELINE, LOOP_MERGE, and ARRAY_PARTITION directives are used to optimize the latency and interval of the proposed system. The performance and resource utilization of the whole system are evaluated by processing defocus images from the real scene with 640×480 pixel size. The system can process about 22 images at 20 MHz working frequency and keep the 93.29% depth accuracy on the 3D objects test, which achieves a real-time state-of-the-art MDFD system by comparing to other recent works. INDEX TERMS 3D reconstruction, FPGA, monocular depth from defocus, vivado high level synthesis.

Interlocking puzzles are intriguing geometric games where the puzzle pieces are held together based on their geometric arrangement, preventing the puzzle from falling apart. High-level-of-difficulty , or simply high-level , interlocking puzzles are a subclass of interlocking puzzles that require multiple moves to take out the first subassembly from the puzzle. Solving a high-level interlocking puzzle is a challenging task since one has to explore many different configurations of the puzzle pieces until reaching a configuration where the first subassembly can be taken out. Designing a high-level interlocking puzzle with a user-specified level of difficulty is even harder since the puzzle pieces have to be interlocking in all the configurations before the first subassembly is taken out. In this paper, we present a computational approach to design high-level interlocking puzzles. The core idea is to represent all possible configurations of an interlocking puzzle as well as transitions among these configurations using a rooted, undirected graph called a disassembly graph and leverage this graph to find a disassembly plan that requires a minimal number of moves to take out the first subassembly from the puzzle. At the design stage, our algorithm iteratively constructs the geometry of each puzzle piece to expand the disassembly graph incrementally, aiming to achieve a user-specified level of difficulty. We show that our approach allows efficient generation of high-level interlocking puzzles of various shape complexities, including new solutions not attainable by state-of-the-art approaches.

The upper reservoir zone of the Lower Cretaceous Kharaib Formation (46–54 m thick in the studied wells) is regarded as the upper portion of a third-order depositional sequence comprising higher-order cycles. Whereas the third-order sequence interpretation is clearly supported by the upward-shoaling trend of the reservoir zone, relationships defining the component cycles have not previously been documented and are the focus of the present study. Core descriptions from four wells in a single oilfield reveal little evidence of facies changes or trends of facies patterns indicative of high-frequency depositional cycles. Cycle boundaries could possibly be represented by the repetitive pattern of coarse beds (rudstone and floatstone) 0.1–2 m thick, commonly having sharp basal contacts and gradational upper contacts with enclosing packstone to wackestone. Because the coarse beds do not appear correlative between wells, however, we prefer the alternative interpretation that they reflect episodic storm events which locally redistributed detritus, sourced from a patchwork of low-relief lithosomes, across the flat surface of the epeiric Kharaib platform–lagoon. Although the existence of high-order eustatic fluctuations during upper Kharaib deposition is well established, low-amplitude variations in water depth may not have touched down on the sea floor to significantly affect sediment textures in contrast with the dominant storm signal.Reservoir sub-zones used for production operations, but previously suggested to be fourth-order parasequence sets, are defined by dips in porosity-log profiles, reflecting thin (approximately 1 m) intervals of increased stylolite frequency. These boundaries are thus diagenetic in character, but their correlation over tens to hundreds of kilometers indicates an underlying depositional control. We suggest that the link between sea level and diagenesis is depositional-clay content, which facilitates stylolitic dissolution. Profiles of bulk-rock alumina analyses in the studied cores show subtle indications of higher clay content at the sub-zone tops. Much greater clay peaks mark the third-order sequence boundaries, resulting in the “dense” (very low porosity) zones above and below the studied reservoir zone and the increased stylolite frequency in the upper and lower several meters of the zone. Possible factors promoting clay influx across a carbonate shelf during falls in sea level include increased stream gradients and more humid climate.

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