Information processing apparatus, control method of the same, and video camera

Patent metadata

Field	Value
Publication number	US-2016196634-A1
Application number	US-201614986858-A
Country	US
Kind code	A1
Filing date	Jan 4, 2016
Priority date	Jan 7, 2015
Publication date	Jul 7, 2016
Grant date	—

Abstract

When deducing a homography matrix representing a geometrical relationship between two images, an image processing apparatus obtains a transformation matrix for four feature points in each of the two images based on reference coordinates. More specifically, the apparatus obtains the area of a triangle formed by three out of the four feature points, and calculates projective parameters of transformation matrices from the area ratios. The apparatus calculates the homography matrix between the images by the product of one of the two obtained matrices and an inverse matrix of the other.

First claim

What is claimed is:

1 . An information processing apparatus comprising:
an area calculator configured to calculate, in each of a first plane and a second plane, an area of a triangle whose apexes are three feature points of four feature points; a first matrix calculator configured to calculate, in each of the first plane and the second plane, a first transformation matrix and a second transformation matrix for transforming four reference feature points into the four feature points, by using the area of the triangle whose apexes are three feature points of the four feature points; and a second matrix calculator configured to calculate a third transformation matrix for transforming the four feature points of the first plane into the four feature points of the second plane, by using the first transformation matrix and the second transformation matrix.

2 . The apparatus according to claim 1 , further comprising a determination unit configured to determine whether the three feature points are arranged on the same straight line,
wherein if the determination unit determines that the three feature points are arranged on the same straight line, the first matrix calculator aborts the calculation using the area of the triangle whose apexes are the three feature points.

3 . The apparatus according to claim 2 , wherein the determination unit determines whether the three feature points are arranged on the same straight line by comparing the area of the triangle whose apexes are the three feature points with a predetermined threshold.

4 . The apparatus according to claim 1 , wherein the second matrix calculator calculates the third transformation matrix by multiplying the second transformation matrix by an inverse matrix of the first transformation matrix.

5 . The apparatus according to claim 1 , wherein the four reference feature points are apexes of a unit square having an origin as one apex.

6 . An information processing apparatus comprising:
a volume calculator configured to calculate, in each of a first space and a second space, a volume of a tetrahedron whose apexes are four feature points of five feature points; a first matrix calculator configured to calculate, in each of the first space and the second space, a first transformation matrix and a second transformation matrix for transforming five reference feature points into the five feature points, by using the volume of the tetrahedron whose apexes are four feature points of the five feature points; and a second matrix calculator configured to calculate a third transformation matrix for transforming the five feature points of the first space into the five feature points of the second space, by using the first transformation matrix and the second transformation matrix.

7 . The apparatus according to claim 6 , further comprising a determination unit configured to determine whether the four feature points are arranged on the same plane,
wherein if the determination unit determines that the four feature points are arranged on the same plane, the first matrix calculator aborts the calculation using the volume of the tetrahedron whose apexes are the four feature points.

8 . The apparatus according to claim 7 , wherein the determination unit determines whether the four feature points are arranged on the same plane by comparing the volume of the tetrahedron whose apexes are the four feature points with a predetermined threshold.

9 . The apparatus according to claim 6 , wherein the second matrix calculator calculates the third transformation matrix by multiplying the second transformation matrix by an inverse matrix of the first transformation matrix.

10 . The apparatus according to claim 6 , wherein the five reference feature points are apexes of a unit cube having an origin as one apex.

11 . An information processing method comprising:
calculating, in each of a first plane and a second plane, an area of a triangle whose apexes are three feature points of four feature points; calculating, in each of the first plane and the second plane, a first transformation matrix and a second transformation matrix for transforming four reference feature points into the four feature points, by using the area of the triangle whose apexes are three feature points of the four feature points; and calculating a third transformation matrix for transforming the four feature points of the first plane into the four feature points of the second plane, by using the first transformation matrix and the second transformation matrix.

12 . A non-transitory computer-readable storage medium storing a program which causes a computer to execute steps of:
calculating, in each of a first plane and a second plane, an area of a triangle whose apexes are three feature points of four feature points; calculating, in each of the first plane and the second plane, a first transformation matrix and a second transformation matrix for transforming four reference feature points into the four feature points, by using the area of the triangle whose apexes are three feature points of the four feature points; and calculating a third transformation matrix for transforming the four feature points of the first plane into the four feature points of the second plane, by using the first transformation matrix and the second transformation matrix.

13 . An information processing method comprising:
calculating, in each of a first space and a second space, a volume of a tetrahedron whose apexes are four feature points of five feature points; calculating, in each of the first space and the second space, a first transformation matrix and a second transformation matrix for transforming five reference feature points into the five feature points, by using the volume of the tetrahedron whose apexes are four feature points of the five feature points; and calculating a third transformation matrix for transforming the five feature points of the first space into the five feature points of the second space, by using the first transformation matrix and the second transformation matrix.

14 . A non-transitory computer-readable storage medium storing a program which causes a computer to execute steps of:
calculating, in each of a first space and a second space, a volume of a tetrahedron whose apexes are four feature points of five feature points; calculating, in each of the first space and the second space, a first transformation matrix and a second transformation matrix for transforming five reference feature points into the five feature points, by using the volume of the tetrahedron whose apexes are four feature points of the five feature points; and calculating a third transformation matrix for transforming the five feature points of the first space into the five feature points of the second space, by using the first transformation matrix and the second transformation matrix.

15 . A video camera comprising:
an imaging unit configured to capture a moving image including a plurality of frame images; and a detector configured to detect, for a first frame image in the moving image, a blurring amount of a second frame image following the first frame image, wherein the detector includes: an area calculator configured to calculate, in each of the first frame image and the second frame image, an area of a triangle whose apexes are three feature points of four feature points; a first matrix calculator configured to calculate, in each of the first frame image and the second frame image, a first transformation matrix and a second transformation matrix for transforming four reference feature points into the four feat

Assignees

• Canon Kk

Inventors

• Mitsunami Koki
• Nakayama Tadayoshi

Classifications

• G06T3/0056 Primary

  Physics · mapped topic

• H04N5/225

  Electricity · mapped topic

• G06T3/10 Primary

  Selection of transformation methods according to the characteristics of the input images · CPC title