INFORMATION PROCESSING APPARATUS, INFORMATION PROCESSING METHOD, POSITION AND ORIENTATION ESTIMATION APPARATUS, AND ROBOT SYSTEM

• US 20150269735A1
• Filed: 03/18/2015
• Published: 09/24/2015
• Est. Priority Date: 03/20/2014
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Tateno, Keisuke
• Granted Patent: US 10,083,512 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06T 2207/30164 Workpiece; Machine component
• CPC Class Codes: G06T 5/70 Denoising; Smoothing
• CPC Class Codes: G06T 7/13 Edge detection
• CPC Class Codes: G06T 7/75 involving models
• CPC Class Codes: G06V 10/28 Quantising the image, e.g. histogram thresholding for discrimination between background and foreground patterns
• CPC Class Codes: G06V 10/44 Local feature extraction by analysis of parts of the pattern, e.g. by detecting edges, contours, loops, corners, strokes or intersections; Connectivity analysis, e.g. of connected components
• CPC Class Codes: G06V 10/443 by matching or filtering
• CPC Class Codes: G06V 10/462 Salient features, e.g. scale invariant feature transforms [SIFT]
• CPC Class Codes: G06V 20/64 Three-dimensional objects

Abstract

An information processing apparatus includes an image acquisition unit, variation amount deriving unit, acquisition unit, and threshold value deriving unit. The image acquisition unit acquires a captured image obtained by an imaging unit. The variation amount deriving unit derives a luminance value variation amount of a predetermined area of the acquired captured image based on a luminance value of the predetermined area and first information indicating a relationship between a captured image luminance value and an amount of luminance value variation. The acquisition unit acquires an amount of variation of a luminance gradient value based on the derived amount of variation of the luminance value, wherein the luminance gradient value is a gradient value of the luminance value. The threshold value deriving unit derives a threshold value with which an obtained luminance gradient value is to be compared, based on the acquired amount of variation of the luminance gradient value.

Claims

1. An information processing apparatus comprising:

an image acquisition unit configured to acquire a captured image obtained by an imaging unit that captures an image;

a storage unit configured to store first information indicating a relationship between a luminance value of an image captured by the imaging unit and an amount of variation of the luminance value;

a variation amount deriving unit configured to derive an amount of variation of a luminance value of a predetermined area of the acquired captured image based on a luminance value of the predetermined area of the acquired captured image and the first information;

an acquisition unit configured to acquire an amount of variation of a luminance gradient value based on the derived amount of variation of the luminance value, wherein the luminance gradient value is a gradient value of the luminance value; and

a threshold value deriving unit configured to derive a threshold value with which a luminance gradient value obtained from the acquired captured image is to be compared, based on the acquired amount of variation of the luminance gradient value.

2. The information processing apparatus according to claim 1, further comprising a filter information storage unit configured to store filter information on filter processing for detecting a feature from the acquired captured image,

wherein the acquisition unit acquires the luminance gradient value based on the filter information, and acquires the amount of variation of the luminance gradient value based on the acquired luminance gradient value and the derived amount of variation of the luminance value.

3. The information processing apparatus according to claim 2, wherein the acquisition unit derives, based on the filter information, second information indicating a relationship between a change in the luminance value and a change in the luminance gradient value, and acquires the amount of variation of the luminance gradient value based on the second information and the derived amount of variation of the luminance value.

4. The information processing apparatus according to claim 1, wherein the acquisition unit acquires the amount of variation of the luminance gradient value based on the derived amount of variation of the luminance value and a preliminarily-measured relationship between an amount of variation of a luminance value and an amount of variation of a luminance gradient value.

5. The information processing apparatus according to claim 1, wherein the first information stored in the storage unit is expressed as a function of a luminance value and an amount of variation of the luminance value.

6. The information processing apparatus according to claim 1, wherein the first information stored in the storage unit is expressed as a table including a luminance value and an amount of variation of the luminance value as items.

7. The information processing apparatus according to claim 6, wherein the detection unit applies a filter for detecting a feature to the acquired captured image to (i) calculate a luminance gradient value for each pixel of the acquired captured image and then (ii) detect the feature based on the calculated luminance gradient value and the derived threshold value.

8. The information processing apparatus according to claim 6, wherein the detection unit detects an edge feature from the acquired captured image.

9. The information processing apparatus according to claim 6, wherein the detection unit detects a point feature or a blob feature.

10. The information processing apparatus according to claim 1, further comprising a detection unit configured to detect a feature from the acquired captured image based on the threshold value derived by the threshold value deriving unit.

11. The information processing apparatus according to claim 1, wherein the acquired captured image is one of a grayscale image, a color image, and a range image.

12. A position and orientation estimation apparatus comprising:

the information processing apparatus according to claim 1;

a second image acquisition unit configured to acquire an image including a target object;

a three-dimensional geometric model storage unit configured to store a three-dimensional geometric model of the target object;

an associating unit configured to associate an image feature detected by the detection unit with a feature of the three-dimensional geometric model; and

a position and orientation estimation unit configured to estimate a position and an orientation of the target object based on a result of the association by the associating unit.

13. A robot system comprising:

the position and orientation estimation apparatus according to claim 12; and

a target object holding unit configured to hold the target object based on a result of the estimation of the position and the orientation of the target object by the position and orientation estimation unit.

14. An information processing method for an information processing apparatus, the information processing method comprising:

acquiring a captured image obtained by an imaging unit that captures an image;

obtaining first information indicating a relationship between a luminance value of an image captured by the imaging unit and an amount of variation of the luminance value;

deriving an amount of variation of a luminance value of a predetermined area of the acquired captured image based on a luminance value of the predetermined area of the acquired captured image and the first information;

acquiring an amount of variation of a luminance gradient value based on the derived amount of variation of the luminance value, wherein the luminance gradient value is a gradient value of the luminance value; and

deriving a threshold value with which a luminance gradient value obtained from the acquired captured image is to be compared, based on the acquired amount of variation of the luminance gradient value.

15. A computer-readable storage medium storing a program to cause a computer to perform an information processing method for an information processing apparatus, the information processing method comprising:

acquiring a captured image obtained by an imaging unit that captures an image;

obtaining first information indicating a relationship between a luminance value of an image captured by the imaging unit and an amount of variation of the luminance value;

deriving an amount of variation of a luminance value of a predetermined area of the acquired captured image based on a luminance value of the predetermined area of the acquired captured image and the first information;

acquiring an amount of variation of a luminance gradient value based on the derived amount of variation of the luminance value, wherein the luminance gradient value is a gradient value of the luminance value; and

deriving a threshold value with which a luminance gradient value obtained from the acquired captured image is to be compared, based on the acquired amount of variation of the luminance gradient value.