| US 7,389,000 B2 | ||
| System and method for detecting obstacle | ||
| Nobuyuki Takeda, Tokyo (Japan); Hiroshi Hattori, Tokyo (Japan); and Kazunori Onoguchi, Tokyo (Japan) | ||
| Assigned to Kabushiki Kaisha Toshiba, Tokyo (Japan) | ||
| Filed on May 23, 2007, as Appl. No. 11/752,565. | ||
| Application 11/752565 is a division of application No. 11/223977, filed on Sep. 13, 2005, granted, now 7,242,817, filed on Jul. 10, 2007. | ||
| Application 11/223977 is a continuation of application No. 10/151804, filed on May 22, 2002, granted, now 6,990,253, filed on Jan. 24, 2006. | ||
| Claims priority of application No. 2001-154569 (JP), filed on May 23, 2001. | ||
| Prior Publication US 2007/0217658 A1, Sep. 20, 2007 | ||
| This patent is subject to a terminal disclaimer. | ||
| Int. Cl. G06K 9/36 (2006.01) | ||
| U.S. Cl. 382—276 [382/103; 382/154; 382/291; 348/135; 348/139; 348/143] | 4 Claims |
| 1. A method for detecting an obstacle by using two cameras, the obstacle being on a reference plane in a field of view common
to the two cameras, the method comprising:
inputting a first image and a second image from the two cameras, respectively;
transforming the first image to a transformed image on a basis of image transform which is introduced from a geometrical relationship
between a reference plane and the two cameras for transforming any given pixel in a reference plane region in the first image
to a corresponding pixel in the second image;
obtaining a degree of similarity D indicating a similarity between an image in a processing region established in the second
image and an image in a corresponding processing region established in the first image and being a function of position in
the vertical direction of the image;
establishing, when any given image line in a specified region in the second image is a contact line of the obstacle with the
reference plane, the processing region for an inter-image arithmetic operation between the first image and the second image,
and a plurality of the processing regions being established with the image line being shifted in the vertical direction;
obtaining a degree of similarity P indicating a similarity between an image in the processing region established in the second
image and an image in a corresponding processing region established in the transformed image and being a function of position
in the vertical direction of the image;
establishing the processing region for an inter-image arithmetic operation between the second image and the transformed image,
and a plurality of the processing regions being established with the image line being shifted in the vertical direction;
detecting the obstacle on a basis of the degree of similarity D and the degree of similarity P on a reference plane region;
obtaining a difference K between the degree of similarity D and the degree of similarity P both obtained as being on the reference
plane region; and
judging that the obstacle is at a position where the difference K is large.
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