Moving Object Detection Apparatus And Method

• US 20090161911A1
• Filed: 04/09/2008
• Published: 06/25/2009
• Est. Priority Date: 12/21/2007
• Status: Active Grant

• Current Assignee: Industrial Technology Research Institute
• Original Assignee: Industrial Technology Research Institute
• Inventors: Shih, Ming-Yu, Chao, Ying-Ying
• Granted Patent: US 8,000,498 B2
• Time in Patent Office: Days
• US Class Current: 382/103
• CPC Class Codes: G06T 2207/10016 Video; Image sequence
• CPC Class Codes: G06T 2207/30232 Surveillance
• CPC Class Codes: G06T 7/254 involving subtraction of images

Abstract

Disclosed is directed to a moving object detection apparatus and method. The apparatus comprises an image capture module, an image alignment module, a temporal differencing module, a distance transform module, and a background subtraction module. The image capture module derives a plurality of images in a time series. The image alignment module aligns the images if the image capture module is situated on a movable platform. The temporal differencing module performs temporal differencing on the captured images or the aligned images, and generates a difference image. The distance transform module transforms the difference image into a distance map. The background subtraction module applies the distance map to background subtraction technology and compares the results with the current captured image, so as to obtain the information for moving objects.

Claims

1. A moving object detection apparatus, comprising:

an image capture module that captures a plurality of images for one or more moving objects at different times;

an image align module that aligns said plurality of images captured at different times if said image capture module is situated on a movable platform;

a temporal differencing module that performs temporal differencing on said captured or aligned images to obtain a difference image;

a distance transform module that transforms said difference image into a distance map; and

a background subtraction module that applies said distance map to a background subtraction technology and compares with a current captured image to obtain moving object information.

2. The apparatus as claimed in claim 1, wherein in the case of a movable platform, said image align module provides one or more alignment parameters to said background subtraction module to obtain said moving object information.

3. The apparatus as claimed in claim 1, wherein in the case of a movable platform, said image align module provides said aligned images to said temporal differencing module.

4. The apparatus as claimed in claim 1, wherein said moving object information at least includes the area where said one or more moving objects occur in the image.

5. The apparatus as claimed in claim 1, wherein said distance map provides a probability distribution of the location for said one or more moving objects.

6. The apparatus as claimed in claim 1, said apparatus is applicable to both movable platform and fixed platform.

7. The apparatus as claimed in claim 6, wherein in the case of a fixed platform, said apparatus does not comprise an image align module.

8. A moving object detection method, comprising the steps of:

capturing a plurality of images for one or more moving objects at different times;

aligning said plurality of images captured at different times if said captured images are on a movable platform;

performing temporal differencing on said captured or aligned images to obtain a difference image;

transforming said difference image into a distance map; and

applying said distance map to a background subtraction technology and comparing with a current captured image to obtain moving object information.

9. The method as claimed in claim 8, wherein in the case of a movable platform, at least an alignment parameter is applied to a pair of said captured images for aligning images at different times.

10. The method as claimed in claim 8, wherein said background subtraction technology at least include:

applying at least an alignment parameter to a background model for said one or more moving objects for aligning said background model to a current captured image;

updating said current captured image into said aligned background model by using said distance map as an updating rate for the background model updating; and

comparing said aligned background model with said current captured image by taking said distance map as a weighting function to perform foreground detection at current time for detecting said one or more moving objects.

11. The method as claimed in claim 8, wherein in the case of movable platform, alignment is performed on neighboring images before temporal differencing to align background area of said neighboring images for compensating the image change caused by the movable platform.

12. The method as claimed in claim 8, wherein said temporal differencing technology is to perform an AND operation on two frame differences obtained from deformation transformation to compute said difference image.

13. The method as claimed in claim 8, wherein the area where said one or more moving objects occur in an image is seen from said distance map.

14. The method as claimed in claim 10, wherein in foreground detection, said distance map is used as an adaptive threshold for foreground determination.

15. The method as claimed in claim 10, wherein in background updating, said distance map is used as an adaptive updating rate.