Patent Publication Number: US-2006001741-A1

Title: Realtime video display method of mixed signals

Description:
FIELD OF THE INVENTION  
      The present invention relates to a video display method of surveillance systems and, more particularly, to a video display method capable of displaying the video images from the mixed signals in real time.  
     BACKGROUND OF THE INVENTION  
      Nowadays, security systems are more and more appreciated in every aspect. The emerging demand of integrated digital surveillance is continuously growing, resulted in recent terrorism and crime wave as well as the needs of global enterprises. The requirement of remote monitoring through the Internet is steadily increased.  
      Generally speaking, surveillance systems mainly include access control systems, alarm/burglarproof systems, and video management systems. The video management system integrates the techniques of camera image input, image processing, and record display. Analog closed-circuit television (CCTV) is the most popular monitoring system today. The disadvanges of CCTV monitoring systems include the quality issue of videotape, signal attenuation, and poor image quality etc., however, they still predominate due to their low prices. Besides, along with digitization and increase of the requirement for remote monitoring, digital image monitoring systems have become the development trend in the future surveillance market and LAN cameras are used for capturing images.  
      In existent surveillance systems, analog signals and digital signals coexist for image display. However, a digital surveillance system can only display digital images, and an analog image monitoring system can only display analog images. Therefore, the present invention aims to propose a realtime video display method of mixed signal so that analog images and digital images can be displayed in real time for video monitoring.  
     SUMMARY OF THE INVENTION  
      An object of the present invention is to provide a realtime video display method of mixed signals, with which analog images and digital images are simultaneously received and displayed on the video monitoring system, hence solving the problem of incompatibility of conventional digital and analog monitoring systems.  
      Another object of the present invention is to let a user be able to connect a monitoring host via the Internet or an intranet for realtime monitoring of image and checking the information of access control and various detectors, hence effectively exploiting a real benefit of surveillance management.  
      To achieve the above objects, the present invention proposes a realtime video display method of mixed signal applied to a video monitoring system. The monitoring system has a monitoring host, which is connected to a plurality of analog monitoring devices via a transmission interface and to a plurality of digital monitoring devices via an Internet/WAN (wide area network)/local area network (LAN). In this method, the digital video data from the Internet/WAN/LAN and the analog video data from the transmission interface are first received. Next, a data fetch server is used to collect the video data for processing and then output the processed video data to a data mixer. The data mixer then merges the digital video data and the analog video data into a signal data source. The digital video data and the analog video data can thus be displayed at a browse terminal in real time.  
      The various objects and advantages of the present invention will be more readily understood from the following detailed description when read in conjunction with the appended drawing, in which: 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is an architecture diagram of a video monitoring system to which the present invention is applied; and  
       FIG. 2  is a flowchart of a realtime video display method of mixed signals of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
      The present invention proposes a realtime video display method applied to a video management system. As shown in  FIG. 1 , the video management system comprises a monitoring host  10  connected to a plurality of external networks  14  via the Internet  12  and to an intranet  16  via a wide area network (WAN)/local area network (LAN). A plurality of digital monitoring devices  18  (i.e., IP cameras) is disposed in the external networks  14  and the intranet  16 . The external networks  14  and the intranet  16  are of TCP/IP architecture, and are usually Ethernet networks. Each of the digital monitoring devices  18  has an IP address assigned to it. The external networks  14  and the intranet  16  are connected with a plurality of analog monitoring devices  20  via a transmission interface. For internal buses, the transmission interface is usually a peripheral component interconnect (PCI). For external buses, the transmission interface is usually universal serial bus (USB) or IEEE 1394 (fire wire). Besides, an I/O controller  22 , an access controller  24 , and a local browse device  26  are disposed in each of the external networks  14  and the intranet  16 . The I/O controller  22  is connected with a plurality of detectors  28 . The access controller  24  is connected with several card readers  30  for access controlling. A local security personnel can use the local browse device  26  to browse local captured images. The detectors  28  usually include components like magnetic contacts, infrared detectors, microwave spatial detectors, glass vibration detectors, smoke detectors, temperature sensors, gas detectors, flame detectors, carbon monoxide detectors, poisonous gas detectors, emergency push-buttons, wireless help seekers, flash alarms, or indication lights.  
      A remote browse terminal  32  is connected with the intranet  16  and the external networks  14  via the Internet  12  so that digital images and analog images can be displayed in real time for remote monitoring.  
       FIG. 2  is a flowchart of a realtime video display method of mixed signals of the present invention. The method comprises the following steps. First, a network communication device is connected to Internet/WAN/LAN and an analog device is connected to a computer bus. Digital video data from the Internet/WAN/LAN is received (Step S 10 ), and analog image data from the bus is received simultaneously (Step S 12 ). The digital video data is captured by a digital monitoring device, and the analog video data is captured by an analog monitoring device. Next, a data fetch server is used to collect the image data and send the analog video for subsequent processing so that the monitoring host can view the analog video data as one whose source is a digital monitoring device (Step S 14 ).  
      After processing of the analog video data, the digital video data and the analog video data are together sent to a data mixer. The data mixer will synchronously process the digital video data and the analog video data to merge mixed signal sources (Step S 16 ). The data mixer can receive image data of different video formats. The format of digital video image is usually MPEG, MPEG2, MPEG4, H.263, or H.264. The format of analog video image is usually NTSC or PAL. After the mixed data sources are formed by merging, they are stored into a database and can be displayed on a browse terminal (Step S 18 ). Finally, the browse terminal can receive the digital signal via the database or the data mixer for realtime and simultaneous display of digital video data and analog video data.  
      The digital signal with mixed data sources can be displayed on the same screen or can display on different screens simultaneously. The browse terminal can be a local browse terminal or a remote browse terminal. If the browse terminal is a remote browse terminal, it is connected to the monitoring host via a network and makes use of a network viewer (e.g., the Microsoft&#39;s IE explorer) to browse the simultaneously displayed digital video and analog video. Moreover, the captured video can be shown on the same monitoring screen, and the video source can be from the analog monitoring devices and/or the digital monitoring devices.  
      The above realtime video display method of mixed signal can be integrated with the same software.  
      Therefore, when the present invention is used in monitoring, analog video from common monitoring cameras can be received, and digital video from IP cameras can also be received. That is, signals of different types can be integrated for realtime display on the same management screen, hence solving the problem of incompatibility of conventional digital and analog monitoring systems. Besides, a user can connect the monitoring host via the Internet or an intranet for realtime monitoring of image, access control, and messages of various detectors, hence effectively exploiting a real benefit of safety management.  
      Although the present invention has been described with reference to the preferred embodiment thereof, it will be understood that the invention is not limited to the details thereof. Various substitutions and modifications have been suggested in the foregoing description, and other will occur to those of ordinary skill in the art. Therefore, all such substitutions and modifications are intended to be embraced within the scope of the invention as defined in the appended claims.