Gaze Selection for Visual Search
Gaze Selection for Visual Search
复制标题
视觉搜索的注视选择
DOI：
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发表时间：
1994
期刊：
影响因子：
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通讯作者：
D. Ballard
中科院分区：
文献类型：
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作者：
L. Wixson;D. Ballard
本论文研究了利用视觉传感器搜索目标物体的问题。特别是，它研究选择一系列视点、观察方向和视野的任务，以有效地检查正在搜索的区域。这由于两个问题而变得困难，即需要高图像分辨率以及存在从某些视点遮挡部分搜索区域的障碍物。 .pp 搜索需要高图像分辨率才能识别的对象可能需要检查大量图像；高分辨率需要狭窄的视野，因此需要更多的图像来跨越给定的视角。本文考虑了一种通过仅搜索那些特别可能包含该对象的子区域来提高搜索效率的方法。使用此方法的搜索称为间接搜索，它重复查找通常参与与目标对象的空间关系的可廉价定位的“中间”对象，然后在该关系指定的受限区域中查找目标。开发了搜索效率的决策理论模型。该模型识别了有用的中间对象的需求，并预测在典型的室内情况下，间接搜索可将效率提高八倍。该模型还适合在在线系统中用于选择中间对象。 .pp 搜索者面临的第二个问题是被搜索区域的某些部分通常是隐藏的。因此，常常需要多种观点。本论文探讨了这些观点的选择。传统的视点选择方法涉及到目前为止所看到的场景部分的详细地图。提出了更简单的无模型方法，尽管对观点的选择性较少，但与基于地图的方法相比，无需付出更多努力即可找到对象。他们认为，选择有效视点序列的主要要求是搜索者拥有一种确保其系统地遍历视点空间的机制。这种机制比地图简单得多。无模型方法的一个缺点是，当对象不存在时，它们在中止之前可能会浪费更多的精力。提出了解决此问题的建议。
This dissertation studies the problem of searching for a target object with a visual sensor. In particular, it studies the task of selecting a sequence of viewpoints, viewing directions, and fields of view that efficiently examines the area being searched. This is made difficult by two problems, namely the need for high image resolution and the presence of obstacles that occlude portions of the search area from certain viewpoints. .pp Searches for objects that require high image resolution to be recognizable can potentially require the examination of a large number of images; high resolution requires a narrow field of view, and hence more images are necessary to span a given visual angle. This dissertation considers a method for increasing search efficiency by searching only those subregions that are especially likely to contain the object. Searches that use this method, called indirect searches, repeatedly find a cheaply-locatable "intermediate" object that commonly participates in a spatial relationship with the target object, and then look for the target in the restricted region specified by this relationship. A decision-theoretic model of search efficiency is developed. The model identifies desiderata for useful intermediate objects and predicts that, in typical indoor situations, indirect search provides up to an eight-fold increase in efficiency. The model is also suitable for use in an on-line system for selecting intermediate objects. .pp The second problem facing a searcher is that portions of the area being searched are often hidden from view. Multiple viewpoints are therefore often necessary. This dissertation examines the selection of such viewpoints. Traditional viewpoint selection methods involve detailed maps of the scene portions viewed so far. Simpler model-free methods are presented that, though less selective about their viewpoints, find objects without significantly more effort than map-based methods. They suggest that the main requirement for selecting efficient viewpoint sequences is that the searcher possesses a mechanism for ensuring that it systematically traverses the viewpoint space. Such mechanisms can be much simpler than maps. One drawback of model-free methods is that when the object is not present, they can waste more effort before aborting. Suggestions for remedying this are presented.