Study Of Edge Cognizing Mechanism Based On The Biologic Characteristics

In machine vision, edges, as images'basic characteristics, are frequently applied in picture cognization of higher levels. Edge cognizing is widely used in many areas such as picture division, image cognization and so on. Also, it is the theoretical foundations of these domains. According to the requirements of picture division and image cognization, the maim work of this paper is as follows:1 We discuss the models of visual information's topological recombination in retinae. The maim contents are as follows: the model of direct synaptic contacts between different cells in retinae; the mechanism of ON/OFF channels'separation in outer plexiform layer; the topological structure of receptive field's centre-surrounding units; the sequential relationship of information transfer in retinae; sorting relationship of cells in retinae; the mechanism of visual information's topological recombination in retinae.2 The essential rules of edge cognizing mechanism are discussed: we probe into the model of the receptive field of simple cells that can cognize edges and the model of simple cells'edge cognizing process.3 The model of moving edge's detection of biologic visual system are discussed: working mechanism of directional selective ganglion cells and the model of hypercomplex cells'edge detecting.4 We simulate the process of biologic retinae's detection of both static and dynamic edges. The mail work is as follows: We simulate the influence of photoreceptors'distributing density to the visual field's detection, the effect of ON/OFF bipolar cells'information separation, the information processing of cells'receptive field'centre-surrounding units and the ganglion cells'processing to the information; Simple cells'detection of horizontal and upright edges is also simulated; We also simulate the ACh amacrine cells'detection to the luminance in their receptive field and directional selective ganglion cells'detection to the moving edges.The conclusions we educe are as follows:①The direct synapses of different neurons is a surjection and the synapses of the midget channel is a bijective mapping; absolutely there are considerable reorganizing and topologic recombining of visual information in three layers of nerve cell bodies and two layers of synapses of retinae;②The separation of ON/OFF channels simplifies the work of the visual cognizing behind and this separation is a commutative group of two elements. The commutation of these kinds exists mainly in outer synaptic layer. When the cognizing reaches some certain level, the signals of the two channels will be combined together in order to accomplish special cognizing task.③The centre and the surrounding of receptive fields in retinae form topological space and both the centre and the surrounding can be embedded in the topological space.④The simple cells'edge cognizing mechanism is simple but effective, not only perceiving edges but also reserving key information, such as the derection of the edge, which will be needed in the visual cognizing later.⑤The receptive fields'different area of the simple cells that can cognize edges of certain directions receive signals from different ON/OFF channels⑥The power of surroundings is greater than 0 but can not counteract the signal of the centers wholly.⑦ON-OFF ACh amacrines themselves can not perceive the moving derection but their detecting of luminance changing is the promise of DSGCs'derection perceving function.⑧There are key relationship between directional selective ganglion cells'detection to special moving direction and a kind of GABA amacrine cells' inhibition to the DS ganglion cells when the moving direction of edge is the NULL one.The models of biologic edge cognizing we discussed in this paper profoundly depict the essential rules of biologic vision system's edge cognizing and open its process and mechanism out; edges perceived by the method concluded from the edge cognizing mechanism of simple cells in V1 own extremely important information that is useful to the later visual cognizing; the discussed mechanism of DSGCs'perception to a certain derection's motion may guide and lead the research of neurons in Lateral Geniculate nuclear (LGN) and V5 (MT).