Method and apparatus for computerized image background analysis

• US 7,460,685 B2
• Filed: 03/13/2007
• Issued: 12/02/2008
• Est. Priority Date: 11/12/2002
• Status: Expired due to Term

• Current Assignee: Johnson Controls Tyco IP Holdings LLP (Johnson Controls International plc)
• Original Assignee: Intellivid Corporation (Johnson Controls International plc)
• Inventors: Buehler, Christopher J.
• Primary Examiner(s): SHERALI, ISHRAT I
• Application Number:
  US11/717,580
• Publication Number:
  US 20070211914A1
• Time in Patent Office: 630 Days
• Field of Search: 382/100, 382/103, 382/173, 382/199, 382224-227, 382/236, 382/107, 348143-159, 348/169, 348162-167, 701/28
• US Class Current: 382/100
• CPC Class Codes: G06T 7/254 involving subtraction of images
• CPC Class Codes: G06V 20/52 Surveillance or monitoring of activities, e.g. for recognising suspicious objects recognising microscopic objects G06V20/69
• 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 13/19608 Tracking movement of a target, e.g. by detecting an object predefined as a target, using target direction and or velocity to predict its new position
• CPC Class Codes: G08B 13/19641 Multiple cameras having overlapping views on a single scene
• CPC Class Codes: G08B 13/19652 Systems using zones in a single scene defined for different treatment, e.g. outer zone gives pre-alarm, inner zone gives alarm
• CPC Class Codes: G08B 13/19656 Network used to communicate with a camera, e.g. WAN, LAN, Internet
• CPC Class Codes: G08B 13/246 Check out systems combined with EAS, e.g. price information stored on EAS tag anti-theft systems in point of sale systems G07G3/003
• CPC Class Codes: H04N 5/272 Means for inserting a foreground image in a background image, i.e. inlay, outlay
• CPC Class Codes: H04N 7/181 for receiving images from a plurality of remote sources

Abstract

A computerized method of video analysis including receiving image data for a plurality of video frames depicting a scene that includes at least one of a plurality of background features. Each video frame includes s a plurality of image regions and at least one video frame has an object within at least one of the image region. A plurality of background classifications is provided that correspond to one of the background features in the scene. At least one image region is assigned a background classification based at least in part on the location of the object relative to the image region.

Claims

1. A computerized method of video analysis, the method comprising:

receiving image data for a plurality of video frames depicting a scene, wherein at least one video frame has an object within such frame, the object having a boundary;

determining a vanishing point for such frame based at least in part on one or more characteristics of the object and the vanishing point of other frames; and

identifying the orientation of the object boundary in the at least one video frame based at least in part on the vanishing point of the frame.

2. The method of claim 1 further comprising determining the vertical vanishing point for such frame based at least in part on one or more characteristics of the object and the vertical vanishing point of other frames.

3. The method of claim 2 wherein the determining of the vertical vanishing point is further based at least on one of a major axis of the object and a centroid of the object.

4. The method of claim 1, wherein the image data further comprises plurality of pixels, the method further comprising selecting at least one the pixels as the boundary based at least in part on the vanishing point of the frame.

5. The method of claim 3 wherein (i) the the boundary comprises a bottom, and (ii) the image data further comprises plurality of pixels, the method further comprising selecting at least one pixel that corresponds to the boundary bottom based at least in part on the vertical vanishing point of the frame.

6. A computerized method for video analysis, the method comprising:

receiving image data for a plurality of video frames depicting a scene that includes at least one of a plurality of background features, wherein (i) each of the video frames comprises a plurality of image regions, and (ii) at least one video frame has an object within at least one image region, the object having a lower boundary;

providing a plurality of background classifications each corresponding to one of the background features in the scene;

determining a vertical vanishing point for the at least one frame in which there is an object based at least in part on one or more characteristics of such object and based on the vertical vanishing point of other frames;

determining the lower boundary of the object; and

assigning one of the background classifications to at least one image region based at least in part on the location of the lower boundary of the object in the frame relative to the image region.

7. The method of claim 6 further comprising counting the number of frames in which a lower boundary of an object is present in each image region.

8. The method of claim 7 further comprising counting the number of frames in which an object is present in each image region.

9. The method of claim 8 wherein the assigning of one of the background classifications to at least one image region further comprises comparing the number of frames in which a lower boundary of an object is present in the image region to a floor threshold.

10. The method of claim 9 wherein the assigning of one of the background classifications to at least one image region further comprises comparing the number of frames in which an object is present in the image region to an obstruction threshold.

11. A video analysis system comprising:

means for receiving image data for a plurality of video frames depicting a scene, wherein at least one video frame has an object within such frame;

means for determining a vanishing point for such frame based at least in part on one or more characteristics of the object and the vanishing point of other frames; and

means for identifying the orientation of the object boundary in the at least one video frame based at least in part on the vanishing point of the frame.