EP1252600A1 - Systeme et procede de controle de changements visibles - Google Patents

Systeme et procede de controle de changements visibles

Info

Publication number
EP1252600A1
EP1252600A1 EP00917672A EP00917672A EP1252600A1 EP 1252600 A1 EP1252600 A1 EP 1252600A1 EP 00917672 A EP00917672 A EP 00917672A EP 00917672 A EP00917672 A EP 00917672A EP 1252600 A1 EP1252600 A1 EP 1252600A1
Authority
EP
European Patent Office
Prior art keywords
image
cells
predetermined
numerical value
computing
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP00917672A
Other languages
German (de)
English (en)
Inventor
designation of the inventor has not yet been filed The
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Bomarc Surveillance Inc
Original Assignee
Bomarc Surveillance Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Bomarc Surveillance Inc filed Critical Bomarc Surveillance Inc
Publication of EP1252600A1 publication Critical patent/EP1252600A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B13/00—Burglar, theft or intruder alarms
    • G08B13/18—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength
    • G08B13/189—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength using passive radiation detection systems
    • G08B13/194—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength using passive radiation detection systems using image scanning and comparing systems
    • G08B13/196—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength using passive radiation detection systems using image scanning and comparing systems using television cameras
    • G08B13/19602—Image analysis to detect motion of the intruder, e.g. by frame subtraction
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B13/00—Burglar, theft or intruder alarms
    • G08B13/18—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength
    • G08B13/189—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength using passive radiation detection systems
    • G08B13/194—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength using passive radiation detection systems using image scanning and comparing systems
    • G08B13/196—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength using passive radiation detection systems using image scanning and comparing systems using television cameras
    • G08B13/19602—Image analysis to detect motion of the intruder, e.g. by frame subtraction
    • G08B13/19606—Discriminating between target movement or movement in an area of interest and other non-signicative movements, e.g. target movements induced by camera shake or movements of pets, falling leaves, rotating fan

Definitions

  • the present invention relates general ly to methods and apparatus for video or other photographic security systems.
  • United States patent number 5.099.322 shows a system for detecting scene changes using a video security system.
  • United States patent number 5.471. 239 show the system for using video frame compression and numerical comparison to detect scene changes.
  • a first image is taken in a predetermined manner of the field of view to be monitored, and then an array divides the first image into a plurality of cells.
  • the first image divided by the array is then stored, and a second image is taken in the predetermined manner of the field of view to be monitored.
  • the array is also applied to the second image, dividing the second image into the plurality of cells.
  • Cells are combined into predetermined groups.
  • the groups could be individual cells, which is to say groups of one cell each.
  • the groups could be rows of cells or columns of cells or rectangular groupings which in effect create larger cells.
  • the predetermined groups of cells of the second image are then compared to the same groups of cells of the first image, and the number of the groups of cells that changed from the first image to the second image is computed. In some situations only certain groups of cells are compared. If a parrot is moving around in a cage, then the cells or the groups of cells which might show the parrot are not compared, or if there are several ceiling fans which are moving, then the cells or the groups of cells which show the ceiling fans might not be compared. There are also other ways of handling these problems which are also described.
  • each cell of the first image is given a numerical value based upon the information in each cell
  • each cell of the second image is also given a numerical value based upon the information in each cell.
  • Each group of cells is also given a numerical value based on the numerical value of the cells within the group. The simplest method is to make the numerical value of each group equal to the sum of the numerical values of the cells within the group, but manipulation would work as long as the numerical value of the group changes when the numerical value of its cells change. Computing how many groups of the cells changed from the first image to the second image is simply a matter of computing the difference between the numerical value of each group of cells in the second image and in the first image.
  • each cell is a single picture element, known as a pixel.
  • a pixel has a its own brightness ranging from 0 for black to a maximum value. typically 255. for white, and the numerical value of each cell is the brightness of the pixel. There is still a brightness number for color images, but color scales could also be used.
  • the numerical value of each group of cells is determined by an image algorithm, which in one preferred form is simply taking the sum of the brightness for the pixels in the group.
  • the predetermined groups of cells comprises a single group. In one method according to the present invention, the number of the groups of cells which changed in numerical value by more than a predetermined amount is also computed.
  • One method also includes the step of comparing the number of the groups of cells that changed from the first image to the second image to a predetermined number. If the parrot moving in its cage, or a cat climbing on the furniture is small enough to never be in more than the predetermined number groups of cells, then if more than the predetermined number groups of cells changed, then it was not caused by the parrot or the cat.
  • Another method, for monitoring a field of view for visible changes includes the steps of taking a sequence of video images in a predetermined manner of the field of view to be monitored, creating a sequence of images, and creating an array which divides each of the images into a plurality of cells.
  • Each image divided by the array is stored and the groups of cells of each image are compared to the same groups of cells of the other images. Again, this could just be predetermined groups of cells which are less than all of the groups of cells. It is then computed if there is a cyclical change in am of the predetermined groups of cells during the sequence. This cyclical change could be the rotation of a ceiling fan or the movement of a flower arrangement caused by the blowing of an air conditioner.
  • each cell of each image is given a numerical value based upon the information in that cell
  • each group of cells is given a numerical value based upon the numerical value of the cells within that group
  • computing if there is a cyclical change in any of the predetermined groups of cells during the sequence becomes computing if there is a cyclical change in any of the numerical values of the predetermined groups of cells during the sequence.
  • the number of the predetermined groups of cells that changed from one image of the sequence to the next image of the sequence and was not part of a cyclical change is computed.
  • FIGURE 1 is a block diagram representation of a system for monitoring a field of view for visible changes in accordance with a present invention:
  • FIGURE 2 is a flow diagram of a method for monitoring a field of view for visible changes in accordance with the present invention:
  • FIGURE 3 is a representation of a first image and array in accordance with the present invention:
  • FIGURE 4 is a representation of a second image and array in accordance with a present invention:
  • FIGURE 5 is an alternative representation of a second image and array in accordance with present invention.
  • FIGURE 6 is a representation of the first image and array of Figure 3 showing the use of a preferred algorithm.
  • a system according to the present invention is referred to generally by reference to 10.
  • Surveillance camera 12 can be in a fixed position and angle with respect to field of view 14 to be monitored, although this is not necessary, and can even work with a fixed lens so that any image that it takes of field of view 14 will be identical except for changes in field of vie 14 itself.
  • Images from video camera 12 are fed to computer 16 where they are input as video images via video image grabber 18.
  • Video image grabber 18 can be anything compatible with the particular video camera, such as a 256 gray scale or a red. green, blue (RGB) scale adapter.
  • the video images are transmitted from video image grabber 18 to both video recorder 20 and image processor 22.
  • Video recorder 20 can be a video cassette recorder (VCR) or a digital versatile disk (DVD. formerly "digital video disk' " ) or some other kind of recorder.
  • VCR video cassette recorder
  • DVD digital versatile disk
  • Figure 3 Figure 4 and Figure 5.
  • method for monitoring a field of view for visible changes is referred to generally by reference in 26.
  • a first or benchmark image 30 is taken by video camera 12 in a predetermined manner of the field of view 14 to be monitored, which is read 32. and then an array 34. which can be a matrix or grid or other array, divides the first image into a plurality of cells 36.
  • the first image divided by the array is then stored, and a second image 38 is taken in the predetermined manner of the field of view to be monitored, which is captured 40.
  • Array 34 is also applied to the second image, dividing the second image into the plurality of cells.
  • the cells of each row R2-1 through R2-10 of the second image are grouped and the cells of each row Rl-1 through Rl -10 of the first image are grouped 42.
  • the rows of the second image are then compared to the rows of the first image, and the number of the rows that changed from the first image to the second image is computed. This could, of course, be done using columns rather than rows, and in a preferred form, rows and columns are alternately compared. In some situations only certain groups are compared. If a parrot is moving around in a cage, then the cells which might show the parrot are not compared, or if there are several ceiling fans which are moving, then the cells which show the ceiling fans might not be compared by the comparison algorithm. There are also other ways of handling these problems which are also shown.
  • a cat 46 has moved into field of view 14 explained the first image and the second image. Cat 46 can occupy up to three rows. The compare against standard 44 portion of the program can simply be instructed to ignore changes in no more than three rows so that the cat will not give a false alarm.
  • an alternative second image is referred to by reference number 48.
  • Human being 50 has entered field of view 14. Human being 50 occupies all ten rows so that there is no danger in the present invention of thus taking human being 50 for cat 46 for vice versa. If columns were used in this case, the man could take two to three columns as could the cat. Alternating comparisons of rows and columns, or comparing both, avoids mistakes from such situations.
  • Figure 5 could, of course, be the first image and Figure 3 be the second image, in which case, the present system would detect human being 50 leaving field of vision 14. In such a case, since human being 50 occupies the same space as he moves, he can move within the image without triggering an alarm, depending on the comparison algorithm used.
  • each cell of the first image is given a numerical value based upon the information in each cell
  • each cell of the second image is also given a numerical value based upon the information in each cell.
  • Computing how many groups of the cells changed from the first image to the second image is simply a matter of computing the difference between the numerical value of each cell in the second image and in the first image.
  • each cell comprises a pixel
  • the numerical value of each cell comprises the brightness of the pixel:
  • the numerical value of each group of cells comprises the sum of the brightness for the pixels in the group.
  • the comparison number is a single number that can be quickly calculated since it is simply the sum of the pixel brightness numbers.
  • each group of cells is a row of cells, wherein a single number can be obtained by a sum of row sums. It would work the same for columns. Once again, a sum of row sums could be used alternately with a row of column sums or both sum of row sums and column sums, again obtaining a single number for comparison, would work as well.
  • a preferred form of the present invention is to compare the image mass of the first image with the image mass of the second image.
  • a guard station to operate with a single monitor, television or other video screen. Whenever a significant change is detected, then the monitor, television or other video screen is switched to that camera where the change was detected, while sounding an audible alarm at the guard station to alert the guard that a change has been detected. Besides relieving the tedium of monitoring many different sites where nothing is happening, it would simplify monitoring so that many different sites could actually be monitored at a police station.
  • w hoever is monitoring the site can display both the benchmark image and the image which changed enough to trigger the alarm in addition to the current image, both of which are stored on video recorder 20 or can view a live image directly from surveillance camera 12. If it appears to be a false alarm, then the person monitoring the site can reset a new benchmark from the computer.
  • the number of the cells or groups of cells and which changed in numerical value by more than a predetermined amount is also computed.
  • One method, according to the present invention also includes the step of comparing 44 the number of the groups of cells that changed from the first image to the second image to a predetermined number. If the parrot moving in its cage, or a cat climbing on the furniture is small enough to never be in more than the predetermined number of groups of cells, then if more than the predetermined number of groups of cells changed, then it was not caused by the parrot or the cat.
  • Another method, for monitoring a field of view for visible changes includes the steps of taking a sequence of video images in a predetermined manner of the field of view to be monitored, creating a sequence of images, and creating an array which divides each of the images into a plurality of cells.
  • Each image divided by the array is stored and groups of the cells of each image are compared to the same groups of cells of the other images. Again, this could just be predetermined groups of cells which add to less than all of the cells. It is then computed if there is a cyclical change in any of the predetermined groups of cells during the sequence. This cyclical change could be the rotation of a ceiling fan or the movement of a flower arrangement caused by the blowing of an air conditioner.
  • each cell of each image is given a numerical value based upon the information in that cell, and computing if there is a cyclical change in any of the predetermined groups of cells during the sequence becomes computing if there is a cyclical change in any of the numerical values of the predetermined groups of cells during the sequence.
  • the number of the predetermined cells that changed from one image of the sequence to the next image of the sequence and was not part of a cyclical change is computed.
  • one image algorithm according to the present invention sums rows or columns of cells by assigning each cell a unique numerical value. In the case illustrated, the cells are numbered from left to right beginning at the top. The value of each cell is added to the value of a row or column if a visible item, other than background such as wallpaper, occupies part of that cell. For the field of view illustrated, a table occupies cells 41.
  • a bookcase occupies cells 4. 5. 6. 14. 15. 16. 24. 25. 26. 34. 35. 36. 44. 45. 46. 54. 55. 56. 64. 65 and 66.
  • a chair occupies cells 39. 48.49. 50. 58.59.60. 68.69.70.78.79 and 80.
  • the value of groups, here a group is a row . far from the top: 15. 45. 75. 144. 408. 498. 588. 380. zero and zero.
  • This algorithm has several advantages over using image compression. The algorithm is very simple, for each cell has affixed value which uses that value when the cell is occupied and a value of zero when that cell is not occupied.
  • the value of a row is equal to the sum of the occupied cell numbers in that row.
  • the value of a column would be the sum of the occupied cell numbers in that column.
  • the sum of row sums or the sum of column sums is the number 2153 shown in the lower right corner. As before, sum of row sums could be alternated with row of column sums or the two could be added together, in which case the number in the lower right corner would be doubled.

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Vision & Pattern Recognition (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Image Analysis (AREA)
  • Image Processing (AREA)
  • Closed-Circuit Television Systems (AREA)

Abstract

Un procédé de contrôle d'un champ de vision (14) pour des changements visibles est décrit. Une première image est prise de manière prédéterminée du champ de vision à contrôler puis un quadrillage divise la première image en plusieurs cellules (36). Une seconde image est prise de manière prédéterminée du champ de vision à contrôler. Le quadrillage est également appliqué à la seconde image (38) pour diviser cette dernière en plusieurs cellules. Des groupes prédéterminés de la cellule de la seconde image sont alors comparés aux mêmes groupes de cellules de la première image, et le nombre de groupes de cellules qui ont changé de la première image à la seconde image est calculé. Dans certaines situations, seuls certains groupes de cellules sont comparés.
EP00917672A 1999-02-26 2000-02-25 Systeme et procede de controle de changements visibles Withdrawn EP1252600A1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US52805699A 1999-02-26 1999-02-26
US528056 1999-02-26
PCT/US2000/004906 WO2000051064A1 (fr) 1999-02-26 2000-02-25 Systeme et procede de controle de changements visibles

Publications (1)

Publication Number Publication Date
EP1252600A1 true EP1252600A1 (fr) 2002-10-30

Family

ID=24104079

Family Applications (1)

Application Number Title Priority Date Filing Date
EP00917672A Withdrawn EP1252600A1 (fr) 1999-02-26 2000-02-25 Systeme et procede de controle de changements visibles

Country Status (2)

Country Link
EP (1) EP1252600A1 (fr)
WO (1) WO2000051064A1 (fr)

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4493420A (en) * 1981-01-29 1985-01-15 Lockwood Graders (U.K.) Limited Method and apparatus for detecting bounded regions of images, and method and apparatus for sorting articles and detecting flaws
US5109435A (en) * 1988-08-08 1992-04-28 Hughes Aircraft Company Segmentation method for use against moving objects
US5375177A (en) * 1991-09-27 1994-12-20 E. I. Du Pont De Nemours And Company Method of identifying and characterizing a valid object by color
US5323470A (en) * 1992-05-08 1994-06-21 Atsushi Kara Method and apparatus for automatically tracking an object
US5864630A (en) * 1996-11-20 1999-01-26 At&T Corp Multi-modal method for locating objects in images
US5815590A (en) * 1996-12-18 1998-09-29 Cal Corporation Target light detection

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO0051064A1 *

Also Published As

Publication number Publication date
WO2000051064A1 (fr) 2000-08-31

Similar Documents

Publication Publication Date Title
EP3016382B1 (fr) Dispositifs et procédés de surveillance
US6335976B1 (en) System and method for monitoring visible changes
US4999614A (en) Monitoring system using infrared image processing
US20180007264A1 (en) Imaging system for immersive surveillance
CN115499586A (zh) 监视系统的图像掩蔽方法
WO2012082127A1 (fr) Système d'imagerie pour surveillance immersive
CN107295230A (zh) 一种基于红外热像仪的微型目标物移动侦测装置及方法
US20020039135A1 (en) Multiple backgrounds
JP5771039B2 (ja) 放置人物検出装置
EP3454254A1 (fr) Appareil de traitement d'image, appareil de fourniture d'image, procédés de commande associés et programme
CN113408479A (zh) 火焰检测方法、装置、计算机设备和存储介质
US20020057840A1 (en) System and method for monitoring visible changes
WO2000051064A1 (fr) Systeme et procede de controle de changements visibles
JPS62136991A (ja) 異常監視装置
JP2008009768A (ja) 動き検出装置及び動き検出方法
JPS63163681A (ja) 自動監視装置
JP3185402B2 (ja) 画像処理侵入者検知装置
Watanabe et al. Event detection for a visual surveillance system using stereo omni-directional system
JPH06223187A (ja) 画像型人体検知装置
KR20000024681A (ko) 산불 감지 방법 및 이를 수행하기 위한 시스템
JPH08124064A (ja) 画像を利用した火災検出および火災時避難誘導装置
JPH05151471A (ja) 監視装置
WO2013072807A1 (fr) Procédé et appareil pour enregistrer une scène
JPS6187490A (ja) 監視装置
JPH09102947A (ja) 動き検出装置、動き検出方法、及びビデオカメラシステム

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20020319

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE FR GB

RIN1 Information on inventor provided before grant (corrected)

Inventor name: BELMARES, ROBERT JOSEPH

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20010927