Method and apparatus for video image processing and recording

• US 5,903,321 A
• Filed: 09/24/1996
• Issued: 05/11/1999
• Est. Priority Date: 09/24/1996
• Status: Expired due to Term

• Current Assignee: Cyberlink Corporation
• Original Assignee: Industrial Technology Research Institute
• Inventors: Kung, Chen-Pang, Tung, Pei-Hui, Juang, Dar-Chang
• Primary Examiner(s): Flynn, Nathan
• Assistant Examiner(s): Srivastava, Vivek
• Application Number:
  US08/718,995
• Time in Patent Office: 959 Days
• Field of Search: 348/220, 348/231-233, 348/715, 348/716, 348/718, 386/33, 386/34, 386/38, 386/69, 386/70, 386/117, 386/124, 386/52
• US Class Current: 348/715
• CPC Class Codes: G08B 13/19663 Surveillance related processing done local to the camera
• CPC Class Codes: G08B 13/19669 Event triggers storage or change of storage policy
• CPC Class Codes: H04N 5/772 the recording apparatus and the television camera being placed in the same enclosure
• CPC Class Codes: H04N 5/907 using static stores, e.g. storage tubes or semiconductor memories H04N5/91 takes precedence
• CPC Class Codes: H04N 5/926 by pulse code modulation H04N5/919 takes precedence
• CPC Class Codes: H04N 7/186 Video door telephones

Abstract

A video image signal processing and recording system provides for operation in a first mode in which real time display of video is provided and in a second mode in which the video image signals are digitized and stored in a memory and being read out and displayed in response to selection of a display mode for the system. In an enhanced mode operation for the system, increasing of the low light intensity value of the displayed real time images or displayed memory images to compensate for low light conditions or for the effects of back lighting. The video image signal processing and recording system is described with reference to an application in a door entry system for a residential building.

Claims

1. A video surveillance system for monitoring and recording images within a surveillance area, comprising:

a video camera for viewing images in said area and for providing analog video image signals;

input means including analog to digital converting means for converting said analog video image signals into digital video image signals;

memory storage means;

a video monitor for displaying video images;

signal processing means for processing said digital video image signals for normally causing said images to be successively displayed in real time on said video monitor, and for selectively storing certain of said digital video image signals in said memory means;

read out means for causing said processing means to read said digital video image signals out of said memory means;

output means including digital to analog signal converting means for converting said digital video image signals read out of said memory means into analog video image signals for application to said video monitor; and

first switch means actuated by an event within said surveillance area and operative to trigger said processing means to store in said memory means certain digital video image signals representing at least a first video image.

2. The system according to claim 1, wherein said processing means is responsive to said first switch means for storing digital video image signals representing second, third and fourth video images, and said system further includes second switch means operative to trigger said read out means to sequentially read out from said memory means video images signals corresponding to said first, second, third and fourth images.

3. The system according to claim 1, wherein said memory means is a dynamic random access memory, and wherein said signal processing means includes means for periodically refreshing said memory.

4. The system according to claim 1, wherein said processing means includes means for preventing the storage in said memory means of digital video image signals representing a second image for a predetermined length of time following an actuation of said first switch means.

5. The system according to claim 1, including means for causing said signal processing means to display on said video monitor an enlarged portion of said first video image.

6. A video surveillance system for monitoring and recording images within a surveillance area, comprising:

a video camera for viewing images in said area and for providing analog video image signals;

analog to digital converting means for sampling said analog signals at a first rate for converting said analog video image signals into digital video image signals;

memory storage means;

a video monitor for displaying video images;

signal processing means for processing said digital video image signals, for normally causing said images to be successively displayed in real time on said video monitor, said signal processing means including sampling means for sampling said sampled signals provided by said analog to digital converting means at a second rate which is different than said first rate, and said signal processing means including means for selectively storing certain of said digital video image signals in said memory means;

means for causing said digital video image signals to be read out of said memory means;

digital to analog signal converting means for converting said digital video image signals read out of said memory means into analog video image signals for application to said video monitor and switch means actuated by an event within said surveillance area and operative to trigger said processing means to store in said memory means certain digital video image signals representing at least a first video image.

7. A video surveillance method for monitoring and recording images within a surveillance area using a video camera, said method comprising the steps of:

viewing said area with said camera to produce analog video image signals representing real time images of said area;

converting said analog video image signals into digital video image signals;

applying said analog signals to a video monitor for providing a real time video display of said images;

triggering a switch based on the occurrence of an event in said area;

storing digital video image signals in a memory when said switch is triggered to thereby capture an image of said area at the time said switch is triggered;

reading said digital video image signals out of said memory;

converting said digital video image signals to analog signals; and

applying said converted analog signals to said video display to thereby display the image of said area occurring at the time of said event.

8. The method according to claim 7, including storing in said memory digital video image data for at least first, second, third and fourth video images and reading out said video image data for said first, second, third and fourth video images to simultaneously display said first, second, third and fourth video images on said video display.

9. The method according to claim 8 including causing display of an enlarged portion of said first video image on said video display.