Mobile detector, mobile detecting program, and mobile detecting method
AssigneeNEC Corporation
InventorKatsuhiko Takahashi
Life of this patent
Estimating the term…
Abstract
When a mobile is detected using an imaging device installed in the mobile, the image of a partial area is enlarged/reduced depending on variation in distance to the detection object mobile and then it is compared under a fixed scale thus causing increase in computation cost. In order to eliminate the need for an enlargement/reduction processing or a deformation correction processing every time when collation is performed, an input image is converted into a virtual plane image having a size or a shape on the image of a detection object mobile which does not vary depending on the distance between the mobiles. Using a pair of virtual plane images obtained at two different times, points are made to correspond and the mobile is detected based on the gap of corresponding points.
Claims15
A mobile detector, comprising:
- a virtual plane image generating device which generates, on an assumption that each pixel of an input image obtained by an imaging device on a mobile corresponds to each point on a virtual plane on a real world parallel to a traveling direction of the mobile, a virtual plane image by converting the input image to an image viewed from a direction perpendicular to the virtual plane;
- and
- a mobile detecting device which relates each of points on two virtual plane images which are generated at two different times, obtains a shift amount between corresponding points, and detects a detection object mobile based on an arrangement of the points having the same shift amount,
- wherein the mobile detecting device determines a presence of the detection object mobile when the number of points having the same shift amount in a partial area of the virtual plane image is equal to or more than a predetermined threshold value.
A non-transitory computer readable recording medium storing a mobile detecting program causing a computer connected to an imaging device installed on a mobile to execute:
- a virtual plane image generating function for generating, on an assumption that each pixel of an input image obtained by an imaging device corresponds to each point on a virtual plane on a real world parallel to a traveling direction of the mobile, a virtual plane image by converting the input image to an image viewed from a direction perpendicular to the virtual plane;
- and
- a mobile detecting function for relating each of points on two virtual plane images which are generated at two different times, obtaining a shift amount between corresponding points, and detecting the detection object mobile based on an arrangement of the points having the same shift amount,
- wherein the presence of the detection object mobile is determined by the mobile detecting function, when the number of points having the same shift amount in a partial area of the virtual plane image is equal to or more than a predetermined threshold value.
A mobile detecting method, comprising:
- taking in an image at every predetermined cycle by an imaging device installed on a mobile;
- generating, on an assumption that each pixel of an input image obtained by an imaging device on a mobile corresponds to each point on a virtual plane on a real world parallel to a traveling direction of the mobile, a virtual plane image by converting the input image to an image viewed from a direction perpendicular to the virtual plane;
- relating the points on the virtual plane image generated immediately before to the points on the virtual plane image generated currently to obtain a shift amount between corresponding points;
- detecting the detection object mobile based on an arrangement of the points having the same shift amount;
- determining the presence of the detection object mobile when the number of points having the same shift amount in a partial area on the virtual plane image is equal to or more than a predetermined threshold value.
A mobile detector, comprising:
- virtual plane image generating means for generating, on an assumption that each pixel of an input image obtained by an imaging device on a mobile corresponds to each point on a virtual plane on a real world parallel to a traveling direction of the mobile, a virtual plane image by converting the input image to an image viewed from a direction perpendicular to the virtual plane;
- and
- mobile detecting means for relating each of points on two virtual plane images which are generated at two different times, obtaining a shift amount between corresponding points, and detecting a detection object mobile based on an arrangement of the points having the same shift amount,
- wherein the mobile detecting means determines a presence of the detection object mobile when the number of points having the same shift amount in a partial area of the virtual plane image is equal to or more than a predetermined threshold value.
Dependencies are inferred from the claim text.