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41.
针对TLD(Tracking-Learning-Detection)算法在光照变化不均、遮挡严重、跟踪目标模糊等情况下会出现跟踪失败的问题,提出一种基于卷积神经网络优化TLD运动手势跟踪算法。选取手势特征作正样本,其背景作负样本,获取手势HOG特征并投入到卷积神经网络中加以训练,得到手势检测分类器,从而确定目标手势区域,实现手势的自动识别;再利用TLD算法对手势进行跟踪与学习,对正负样本进行估计检测并实时校正,同时运用SURF特征匹配更新跟踪器。实验结果验证,该算法对比TLD经典算法跟踪精度提高了4.24%,增强了运动手势的跟踪效果,相比经典跟踪算法拥有更高鲁棒性。 相似文献
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Peerapong Wongthahan Amporn Sae-Eaw Witoon Prinyawiwatkul 《International Journal of Food Science & Technology》2020,55(7):2841-2850
This study was performed to develop lexicon to describe soy sauces using regular users (consumers) vs. culinary chefs, to perform product grouping using a free-sorting task and to determine relationship among physicochemical properties (colour, %NaCl) and consumer perception of soy sauces. Both panels identified eighteen terms to describe soy sauces, of which eleven terms (light, medium and dark brown colour, weak, medium and strong saltiness, sweetness, saltiness–sweetness, tasty/umami, and soy sauce and fermented aroma) were similar. For culinary chefs, three distinctive soy sauce groups based on brown colour (light, medium and dark brown) were identified, while two groups (light and medium dark brown) for regular users. From free-sorting maps, both panels associated brown colour intensity with saltiness expectation/perception. From PCA biplots, both panels shared some similarities for sensory liking (colour, saltiness, flavour, overall liking) for soy sauces. This study suggested that brown colour intensities affected saltiness expectation/perception and were used for product grouping for soy sauces. 相似文献
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随着自主式水下机器人的发展,水下探测技术成为新的研究热点。然而,吸收效应和散射效应导致水下获取的图像存在雾化和色彩偏差等缺陷。降质的水下图像在一定程度上降低了水下目标识别的准确性。为了改善水下图像质量,国内外学者对水下图像处理方法进行了深入研究。因水下图像处理方法对提升水下目标识别准确性具有良好的促进作用,故其具有重要的研究与分析价值。介绍了水下成像模型,分析了水下图像视觉质量下降的原理;根据水下物理成像模型将水下图像处理方法分为水下图像增强与水下图像复原,并分别对两类方法的研究现状进行分析与归纳;最后,总结与讨论了各类方法的优缺点,并展望了未来的发展方向。 相似文献
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Aishwarya
Srivastava Siddhant Aggarwal Amy Apon Edward Duffy Ken Kennedy Andre Luckow Brandon Posey Marcin Ziolkowski 《Software》2020,50(6):868-898
We investigate the challenges of building an end-to-end cloud pipeline for real-time intelligent visual inspection system for use in automotive manufacturing. Current methods of visual detection in automotive assembly are highly labor intensive, and thus prone to errors. An automated process is sought that can operate within the real-time constraints of the assembly line and can reduce errors. Components of the cloud pipeline include capture of a large set of high-definition images from a camera setup at the assembly location, transfer and storage of the images as needed, execution of object detection, and notification to a human operator when a fault is detected. The end-to-end execution must complete within a fixed time frame before the next car arrives in the assembly line. In this article, we report the design, development, and experimental evaluation of the tradeoffs of performance, accuracy, and scalability for a cloud system. 相似文献
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Small group detection and tracking in crowd scenes are basis for high level crowd analysis tasks. However, it suffers from the ambiguities in generating proper groups and in handling dynamic changes of group configurations. In this paper, we propose a novel delay decision-making based method for addressing the above problems, motivated by the idea that these ambiguities can be solved using rich temporal context. Specifically, given individual detections, small group hypotheses are generated. Then candidate group hypotheses across consecutive frames and their potential associations are built in a tree. By seeking for the best non-conflicting subset from the hypothesis tree, small groups are determined and simultaneously their trajectories are got. So this framework is called joint detection and tracking. This joint framework reduces the ambiguities in small group decision and tracking by looking ahead for several frames. However, it results in the unmanageable solution space because the number of track hypotheses grows exponentially over time. To solve this problem, effective pruning strategies are developed, which can keep the solution space manageable and also improve the credibility of small groups. Experiments on public datasets demonstrate the effectiveness of our method. The method achieves the state-of-the-art performance even in noisy crowd scenes. 相似文献
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