METHOD AND APPARATUS TO SELECT THE BEST VIDEO FRAME TO TRANSMIT TO A REMOTE STATION FOR CCTV BASED RESIDENTIAL SECURITY MONITORING

• US 20020067258A1
• Filed: 12/06/2000
• Published: 06/06/2002
• Est. Priority Date: 12/06/2000
• Status: Active Grant

• Current Assignee: Signify Holding B.V. (Signify N.V.)
• Original Assignee: Philips Electronics North America Corporation (Koninklijke Philips N.V.)
• Inventors: Gutta, Srinivas, Cohen-Solal, Eric, Colmenarez, Antonio Jr., Lyons, Damian M.
• Granted Patent: US 6,411,209 B1
• Time in Patent Office: Days
• US Class Current: 340/541
• CPC Class Codes: G06V 40/161 Detection; Localisation; Normalisation
• CPC Class Codes: G08B 13/19602 Image analysis to detect motion of the intruder, e.g. by frame subtraction
• CPC Class Codes: G08B 13/19604 involving reference image or background adaptation with time to compensate for changing conditions, e.g. reference image update on detection of light level change
• CPC Class Codes: G08B 13/19669 Event triggers storage or change of storage policy
• CPC Class Codes: H04N 7/181 for receiving images from a plurality of remote sources

Abstract

A security monitoring system including: an alarm system having detectors for detection of an alarm in a structure; at least one camera for capturing image data inside and/or outside the structure; a processor for selecting a subset of the image data upon the occurrence of the alarm based on a predetermined criteria; and a modem for transmitting the subset of image data to a remote location. Preferably, the at least one camera is a video camera, the image data is video image data, and the subset of the image data is at least one video frame of the video image data. Preferably, the processor ranks each video frame from the image data according to how well each video frame meets the predetermined criteria and the modem transmits a predetermined number of video frames having the best rank to the remote location. Preferably, the predetermined criteria is selected from a group consisting of: how centered a difference region is in the video frame; how large the difference region is; whether the difference region consists of a large difference region or a group of smaller difference regions; the contrast of the difference region; the lighting condition on the difference region; whether a face is detected in the difference; whether the video frame is blurred; how much skin color is contained in the video frame; if a person is recognized in the video frame; and the lighting condition on a region of motion in the video frame.

Claims

1. A security monitoring system comprising:

an alarm system having means for detection of an alarm in a structure;

at least one camera for capturing image data inside and/or outside the structure;

a processor for selecting a subset of the image data upon the occurrence of the alarm based on a set of predetermined criteria; and

transmission means for transmitting the subset of image data to a remote location.

2. The security monitoring system of claim 1, wherein the at least one camera is a video camera, the image data is video image data, and the subset of the image data is at least one video frame of the video image data.

3. The security monitoring system of claim 1, wherein the processor is a computer vision system for analyzing the image data according to the predetermined criteria.

4. The security monitoring system of claim 3, further comprising an image recording system for recording the image data to be analyzed by the computer vision system.

5. The security monitoring system of claim 4, wherein the image data is recorded for a predetermined time period before and after the occurrence of the alarm.

6. The security monitoring system of claim 4, wherein the image data is analog image data, the system further comprising an analog to digital converter for converting the analog image data to digital image data prior to being analyzed by the computer vision system.

7. The security monitoring system of claim 1, further comprising a compression means for compressing the subset of the image data prior to transmission to the remote location.

8. The security monitoring system of claim 1, wherein the transmission means is a modem for transmitting the subset of image data to a remote location over a data link operatively connected to the modem and the remote location.

9. The security monitoring system of claim 1, wherein the at least one camera is a video camera, the image data is video image data, and the subset of the image data is at least one video frame of the video image data, wherein the processor ranks each video frame from the image data according to how well each video frame meets the predetermined criteria and the transmission means transmits a predetermined number of video frames having the best rank to the remote location.

10. The security monitoring system of claim 1, wherein the at least one camera is a video camera, the image data is video image data, and the subset of the image data is at least one video frame of the video image data, wherein the processor subtracts an established background from each video frame resulting in a difference region, and wherein the predetermined criteria are selected from a group consisting of:

how centered the difference region is in the video frame;

how large the difference region is in the video frame;

whether the difference region consists of a large difference region or a group of smaller difference regions in the video frame;

the contrast of the difference region in the video frame;

the lighting condition on the difference region in the video frame; and

whether a face is detected in the difference region in the video frame.

11. The security monitoring system of claim 10, wherein if the set of predetermined criteria includes whether a face is detected in the difference region of the video frame, a further set of predetermined criteria is selected from a group consisting of:

how much of the face is visible in the video frame;

whether the face is turned towards or away from the video frame; and

whether key features of the face are visible in the video frame.

12. The security monitoring system of claim 1, wherein the at least one camera is a video camera, the image data is video image data, and the subset of the image data is at least one video frame of the video image data, and wherein the predetermined criteria are selected from a group consisting of:

whether the video frame is blurred;

how much skin color is contained in the video frame;

if a person is recognized in the video frame; and

the lighting condition on a region of motion in the video frame.

14. The method of claim 13, further comprising the step of recording the image data.

15. The method of claim 14, wherein the recording step comprises recording the image data for a predetermined time period before and after the occurrence of the alarm.

16. The method of claim 14, wherein the image data is analog image data, the method further comprising the step of converting the analog image data to digital image data.

17. The method of claim 13, further comprising the step of compressing the subset of the image data prior to transmission to the remote location.

18. The method of claim 13, wherein the image data is video image data and the subset of the image data is at least one video frame of the video image data, wherein the method further comprises the step of ranking each video frame from the image data according to how well each video frame meets the predetermined criteria and the transmission means transmits a predetermined number of video frames having the best rank to the remote location.

19. The method of claim 13, wherein the image data is video image data and the subset of the image data is at least one video frame of the video image data, wherein the method further comprises the step of subtracting an established background from each video frame resulting in a difference region, and wherein the predetermined criteria are selected from a group consisting of:

how centered the difference region is in the video frame;

how large the difference region is in the video frame;

whether the difference region consists of a large difference region or a group of smaller difference regions in the video frame;

the contrast of the difference region in the video frame;

the lighting condition on the difference region in the video frame; and

whether a face is detected in the difference region in the video frame.

20. The method of claim 19, wherein if the predetermined criteria includes whether a face is detected in the difference region of the video frame, a further set of predetermined criteria are selected from a group consisting of:

how much of the face is visible in the video frame;

whether the face is turned towards of away from the video frame; and

whether key features of the face are visible in the video frame.

21. The method of claim 1, wherein the image data is video image data and the subset of the image data is at least one video frame of the video image data, and wherein the set of predetermined criteria are selected from a group consisting of:

whether the video frame is blurred;

how much skin color is contained in the video frame;

if a person is recognized in the video frame; and

the lighting condition on a region of motion in the video frame.

13. A method for monitoring a structure, the method comprising the steps of:

detecting an alarm in the structure;

capturing image data inside and/or outside the structure;

selecting a subset of the image data upon the occurrence of the alarm based on a set of predetermined criteria; and

transmitting the subset of image data to a remote location.