Though there is some evidence concerning the spatial extent of object recognition, the following questions still remain unknown: (a) how large is the FA for rapid object categorization, (b) how accuracy of attention is distributed over the FA, and (c) how fast complex objects can be categorized when presented against backgrounds formed by natural scenes.
Object based image analysis (OBIA) software can be trained to extract the spatial extent of specific objects or features from medium and high resolution images using machine learning techniques with user-defined spectral, spatial, temporal and ancillary information [35, 45].
The required level of decomposition is related to the spatial extent of the objects in the input images and the observation distance.
In addition, the extent of their object-based attention for algebraic sub-expressions predicted their performance on a purely mathematical task, with performance improving as object-based attention increased.
Descartes held that size is perceived by combining visual angle with perceived distance, but he now treated visual angle as the extent of an object's projection onto the retina.
While these examples both draw on the same concept of space ("extent of an object"), the notion of spatial thinking provided by the National Research Council (2006) highlights that the contexts of use and forms of representation used by an engineer and a mathematician as well as the rationale propelling their lines of work differ in important ways.
The vertical angular extent of the object is also reduced, but the horizontal angular extent is unaffected by the cylindrical lenses, as is shown in Fig. 3.
As the extent of an object's convex hull is dictated solely by its geometric extremes, we were able to minimize the amount of skeletal reconstruction in our model (electronic supplementary material, figure S1).
The Gabor filter half-width in the image plane defines the extent of the object area being analyzed and is inversely proportional to the filter half-width in the Fourier plane.
They interpreted this as an implicit measure of an increase in the perceived distance for a situated observer: The angular horizontal extent of the object was unaffected optically; thus, the greater perceived width seemed to be due to an increase in the apparent viewing distance (see Fig. 3).
