Intruding object detecting method and intruding object monitoring apparatus employing the method

• US 7,215,795 B2
• Filed: 09/28/2001
• Issued: 05/08/2007
• Est. Priority Date: 09/28/2000
• Status: Expired due to Fees

• Current Assignee: Hitachi Kokusai Electric Incorporated (Hitachi, Ltd.)
• Original Assignee: Hitachi Kokusai Electric Incorporated (Hitachi, Ltd.)
• Inventors: Ito, Wataru, Ueda, Hirotada, Fujii, Miyuki, Okada, Toshimichi
• Primary Examiner(s): Bali; Vikkram
• Assistant Examiner(s): BHATNAGAR, ANAND P
• Application Number:
  US09/964,336
• Publication Number:
  US 20020051058A1
• Time in Patent Office: 2,048 Days
• Field of Search: 382/100, 382/103, 382/104, 382/107, D16/203, 348/169
• US Class Current: 382/103
• 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

Abstract

An intruding object detecting method and an intruding object monitoring apparatus for detecting a target object intruding into an image pickup region while reducing the error detection of moving objects other than the target object. A difference in pixel value between an input image signal and each of different image signals in a predetermined number of frames greater than one is calculated for each pixel to thereby obtain differential images in the predetermined number of frames. The differential images in the predetermined number of frames are synthesized in predetermined proportions to thereby generate a synthesized differential image. The synthesized differential image is binarized on the basis of a predetermined threshold value to thereby generate a binarized image. A binarized object in the binarized image is detected as an object intruding into a monitoring visual field.

Claims

1. An object detecting method for detecting an object in an image obtained from an image pickup means, comprising:

a frame subtraction step of executing a plurality of frame subtraction processings each frame subtraction processing being between an input image from the image pickup means and respective ones of a plurality of images each having a different time interval with respect to the time interval of said input image;

a synthesizing step of adding together a plurality of differential images obtained by said frame subtraction processings based on coefficients which are set for respective ones of predetermined regions of the image; and

an object detecting step of detecting an object based on data obtained from said synthesizing step.

2. An object detecting method according to claim 1, wherein said coefficients are set based on a distance from the image pickup means.

3. An object detecting method according to claim 1, wherein said coefficients are set based on a magnitude of movement of an object in a respective one of predetermined regions of said image.

4. An object detecting method for detecting an object in an image obtained from an image pickup means, comprising:

a frame subtraction step of executing a plurality of frame subtraction processings each frame subtraction processing being for each of a plurality of predetermined regions,

wherein each of the predetermined regions has a frame time interval which is changed from the frame time intervals of each of the other predetermined regions; and

an object detecting step of detecting an object based on a plurality of differential images obtained from said frame subtraction proessings.

5. An object detecting method according to claim 4, wherein said frame time interval is set based on a distance from said image pickup means.

6. An object detecting method according to claim 4, wherein said frame time interval is set based on a magnitude of movement of an object tin respective one of predetermined regions of said image.

7. An object detecting apparatus for detecting an object in an image obtained from image pickup means, comprising:

frame subtraction means for executing a plurality of frame subtraction processings each frame subtraction processing being between an input image from the image pickup means and respective ones of a plurality of images each having a different time interval with respect to the time interval of said input image;

synthesizing means for adding together a plurality of differential images obtained by said frame subtraction processings based on coefficients which are set for respective ones of predetermined regions of the image; and

object detecting means for detecting an object based on data obtained from said synthesizing means.

8. An object detecting apparatus according to claim 7, wherein said coefficients are set based on a distance from said image pickup means.

9. An object detecting apparatus according to claim 7, wherein said coefficients are set based on a magnitude of movement of an object in respective one of predetermined regions of said image.

10. An object detecting apparatus for detecting an object in an image obtained from an image pickup means, comprising:

frame subtraction means for executing a plurality of frame subtraction processings each frame subtraction processing being for each of a plurality of predetermined regions,

wherein each of the predetermined regions has a frame time interval which is changed from the frame time intervals of each of the other predetermined regions; and

object detecting means for detecting an object based on a plurality of differential images obtained from said frame subtraction processings performed by said frame subtraction means.

11. An object detecting apparatus according to claim 10, wherein said frame time interval is set based on a distance from said image pickup means.

12. An object detecting apparatus according to claim 10, wherein said frame time interval is set based on a magnitude of movement of an object in a respective one of the predetermined regions of said image.