1. A neural network-controlled automatic tracking and recognizing system, comprising: a fixed field of view collection module, said fixed field of view collection module comprising a plurality of sensing cameras for collecting view images of fixed spots; a full functions variable field of view collection module, said full functions variable field of view collection module comprising a plurality of full functions tracking camera for catching images of a suspect moving object appeared in the coverage of said fixed field of view collection module within 360-degrees; a video image recognition algorithm module comprising a series of algorithms adapted for picking up a target object from video images collected by said full functions variable field of view collection module for analysis to identify the characteristic parts of the target object such as human face and car license number; a neural network control module for controlling angle matching of said full functions tracking cameras with said sensing cameras and for controlling the angle of rotation, focus and aperture of said full functions tracking cameras subject to the allowable moving object moving direction in the fixed field of view so that said full functions cameras are controlled to track every suspect moving object and to catch the detail characteristics of every suspect moving object; a suspect object track-tracking module adapted for tracking the track of the suspect target such as human face or object gravity center subject the images obtained through said sensing cameras, and recording/building up the motion track of the suspect object subject to the recognition results of the algorithms of said video image recognition algorithm module; a database comparison and alarm judgment module adapted for fetching human face data, suspect object characteristic data, and other related database data for comparison subject to the recognition results of the algorithms of said video image recognition algorithm module, and determining a report of alarm of “cross border”, “enter restricted area”, “wrong moving direction”, etc., subject to set rules; a monitored characteristic recording and rule setting module adapted for the input of characteristics of target object, such as human face image, to establish a database, and for the setting of alarm rule and sensitivity grade subject to requirements of the monitored area; a light monitoring and control module adapted for analyzing surrounding light status subject to video images obtained through the sensing cameras and full functions tracking cameras of said fixed field of view collection module and said full functions variable field of view collection module, and controlling a backlight module to provide back light when the surrounding light is insufficient for monitoring; a backlight module controllable by said light monitoring and control module to turn on infrared light source means and artificial light source means thereof to provide a backlight subject the condition of the monitored site; an alarm output/display/storage module adapted for displaying alarm information and relay output and for management and storage of monitored video images and alarm information; and security monitoring sensors linked with other security monitoring systems in such a manner that when the security monitoring sensors are started, said full functions tracking cameras are controlled to catch the desired data.