IMAGE PROCESSING DEVICE, IMAGE PROCESSING METHOD AND PROGRAM

• US 20110135158A1
• Filed: 12/02/2010
• Published: 06/09/2011
• Est. Priority Date: 12/08/2009
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Nishino, Katsuaki, Tsunashima, Nobuhiro
• Granted Patent: US 8,630,453 B2
• Time in Patent Office: Days
• US Class Current: 382/107
• CPC Class Codes: G06T 2207/10016 Video; Image sequence
• CPC Class Codes: G06T 2207/30196 Human being; Person
• CPC Class Codes: G06T 2207/30232 Surveillance
• CPC Class Codes: G06T 7/246 using feature-based methods, e.g. the tracking of corners or segments
• CPC Class Codes: G06T 7/269 using gradient-based methods

Abstract

Provided is an image processing device which includes an optical flow computation unit computing optical flow within an image with reference to a past image, an optical flow detection unit setting multiple reference points in a partial region of the image and detecting whether or not optical flow is generated at the reference points, a feature point data storage unit storing, when optical flow is generated at the reference points, as a feature point a set of peaces of pixel data that generated the optical flow, a feature point tracking unit tracking a motion position of the feature point, a feature point deletion unit deleting the tracked feature point in accordance with a variation in motion position of the feature point, and a passage determination unit determining whether or not passage of an object is detected within the image based on multiple remaining undeleted feature points.

Claims

1. An image processing device comprising:

an optical flow computation unit that computes optical flow within an image with reference to a past image;

an optical flow detection unit that sets multiple reference points in a partial region of the image and detects whether or not optical flow is generated at the reference points;

a feature point data storage unit that stores, when optical flow is generated at the reference points, as a feature point a set of peaces of pixel data that generated the optical flow;

a feature point tracking unit that tracks a motion position of the feature point;

a feature point deletion unit that deletes the tracked feature point in accordance with a variation in motion position of the feature point; and

a passage determination unit that determines whether or not passage of an object is detected within the image based on multiple remaining undeleted feature points.

2. The image processing device according to claim 1,

wherein the passage determination unit determines whether or not passage of an object is detected within the image, based on the number of the multiple remaining undeleted feature points of multiple feature points generated at the same time when the optical flow was generated.

3. The image processing device according to claim 1,

wherein the passage determination unit determines whether or not passage of an object is detected within the image, based on a distance between the multiple remaining undeleted feature points and motion directions of the multiple remaining undeleted feature points.

4. The image processing device according to claim 1,

wherein the feature point deletion unit deletes the tracked feature point based on a motion direction of the feature point.

5. The imaging processing device according to claim 1,

wherein the feature point deletion unit deletes the tracked feature point based on motion speed of the feature point.

6. The imaging processing device according to claim 1,

wherein the feature point deletion unit deletes the tracked feature point based on relationship between a feature point and another feature point.

7. The image processing device according to claim 1,

wherein the feature point deletion unit deletes the tracked feature point based on tracking elapsed time of the feature point.

8. An image processing method, comprising the steps of:

computing optical flow within an image with reference to a past image by an optical flow computation unit;

setting multiple reference points in a partial region of the image and detecting whether or not optical flow is generated at the reference points by an optical flow detection unit;

storing, when optical flow is generated at the reference points, as a feature point a set of peaces of pixel data that generated the optical flow by a feature point data storage unit;

tracking a motion position of the feature point by a feature point tracking unit;

deleting the tracked feature point in accordance with a variation in motion position of the feature point by a feature point deletion unit; and

determining whether or not passage of an object is detected within the image based on multiple remaining undeleted feature points by a passage determination unit.

9. A program for causing a computer to perform the steps of:

computing optical flow within an image with reference to a past image;

setting multiple reference points in a partial region of the image and detecting whether or not optical flow is generated at the reference points;

storing, when optical flow is generated at the reference points, as a feature point a set of peaces of pixel data that generated the optical flow;

tracking a motion position of the feature point;

deleting the tracked feature point in accordance with a variation in motion position of the feature point; and

determining whether or not passage of an object is detected within the image based on multiple remaining undeleted feature points.