Detecting apparatus, detecting system, and detecting method

• US 9,293,022 B2
• Filed: 10/29/2014
• Issued: 03/22/2016
• Est. Priority Date: 11/19/2013
• Status: Expired due to Fees

• Current Assignee: Renesas Electronics Corporation
• Original Assignee: Renesas Electronics Corporation
• Inventors: Kurosawa, Takayuki, Tanimoto, Tadaaki
• Primary Examiner(s): NAKHJAVAN, SHERVIN K
• Application Number:
  US14/526,683
• Publication Number:
  US 20150139504A1
• Time in Patent Office: 510 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: G06T 2207/10016 Video; Image sequence
• CPC Class Codes: G06T 2207/20021 Dividing image into blocks, subimages or windows
• CPC Class Codes: G06T 2207/30196 Human being; Person
• CPC Class Codes: G06T 7/215 Motion-based segmentation
• CPC Class Codes: G06V 40/20 Movements or behaviour, e.g. gesture recognition recognition of facial expressions G06V40/16
• CPC Class Codes: G08B 21/0415 detecting absence of activity per se
• CPC Class Codes: G08B 21/0476 Cameras to detect unsafe condition, e.g. video cameras
• CPC Class Codes: G08B 29/185 Signal analysis techniques for reducing or preventing false alarms or for enhancing the reliability of the system

Abstract

The present invention provides a detecting apparatus for detecting an abnormal state such as a drop or fall of a person to be observed from a captured image in a real-time manner and realizing improvement in precision of the detection while eliminating the influence of a background image and noise. The detecting apparatus calculates a motion vector of each of blocks of an image of video data, and extracts a block group in which the size of the motion vector exceeds a predetermined value. The detecting apparatus forms a group from adjacent blocks. For example, in descending order of the area of the blocks, the detecting apparatus calculates characteristic amounts such as an average vector, a variance, and a rotation direction component of motion blocks included in the blocks. The detecting apparatus detects that the person to be observed is in an abnormal state such as a drop or fall on the basis of the characteristic amounts of the groups, and informs an external apparatus or the like of the detection result. The detecting apparatus corrects a deviation of the angle of the imaging direction on the basis of a process of reducing pixels in the horizontal direction of an image and acceleration of the camera, thereby improving the precision of the detection.

Claims

1. A detecting apparatus for detecting a motion state of a person to be observed from an image captured, comprising:

an input/output unit;

a memory for storing video data which is received by the input/output unit; and

a control unit controlling a process of detecting a motion state of the person to be observed on the basis of the video data stored in the memory,

wherein the control unit comprises;

a calculating unit calculating a motion vector of each of a plurality of blocks of an image including the video data;

a detecting unit extracting a block group as a set of the blocks in each of which the size of the motion vector exceeds a predetermined value on the basis of the calculated motion vectors and detecting an abnormal motion state of the person to be observed on the basis of the motion vectors of the blocks included in the extracted block group, and

an informing control unit outputting a signal indicative of an abnormal state of the person to be observed in the case where the abnormal motion state of the person to be observed is detected by the detecting unit.

2. The detecting apparatus according to claim 1, wherein the detecting unit comprises:

a grouping unit extracting and grouping adjacent blocks in each of which the size of the calculated motion vector exceeds a first threshold;

a characteristic amount calculating unit calculating a characteristic amount of a motion vector of each group on the basis of the motion vectors of the blocks including each of the groups formed, and

a determining unit detecting an abnormal motion state of the person to be observed on the basis of the calculated characteristic amount of the motion vector of each of the groups.

3. The detecting apparatus according to claim 2, wherein the grouping unit sets priority on the basis of the number of blocks included in one or more groups formed, and

the characteristic amount calculating unit calculates the characteristic amounts of the motion vectors in the groups in accordance with the priority set for the groups.

4. The detecting apparatus according to claim 2,

wherein the characteristic amount of the motion vector in each of the groups calculated by the characteristic amount calculating unit includes at least any of an average value of gravity force direction components of the motion vectors of the blocks included in each of the groups, a variance value of the motion vectors of the blocks, and the values of the rotation direction components made by the motion vectors of the blocks including the group in the case where the gravity center position of each group is set as a center, and

the determining unit detects the state of the person to be observed on the basis of the characteristic amount calculated by the characteristic amount calculating unit.

5. The detecting apparatus according to claim 4,

wherein the determining unit compares an average value of the motion vectors of the blocks calculated by the characteristic amount calculating unit with a second threshold and, in the case where the average value exceeds the second threshold, detects that the state of the person to be observed is an abnormal motion state.

6. The detecting apparatus according to claim 4,

wherein the determining unit compares a variance value of the motion vectors of the blocks calculated by the characteristic amount calculating unit with a second threshold and, in the case where the variance value does not exceed the second threshold, detects that the state of the person to be observed is an abnormal motion state.

7. The detecting apparatus according to claim 4,

wherein the determining unit compares a value of the rotation direction component calculated by the characteristic amount calculating unit with a second threshold and, in the case where the value of the rotation direction component exceeds the second threshold, detects that the state of the person to be observed is an abnormal motion state.

8. The detecting apparatus according to claim 4,

wherein the determining unit determines motion states of a plurality of groups and, on the basis of a combination of the determination results of the groups, determines the degree of an abnormal motion state of the person to be observed.

9. The detecting apparatus according to claim 1,

wherein the control unit includes a thinning processing unit performing a thinning process of reducing pixels in the horizontal direction, of the video data stored in the memory, and

the calculating unit calculates a motion vector of the video data obtained by reducing the pixels in the horizontal direction by the thinning processing unit.

10. The detecting apparatus according to claim 9,

wherein the control unit receives information of acceleration of a camera which generates the video data by the input/output unit and stores it into the memory, and

the thinning processing unit corrects at least any of a deviation of a pitch angle of the camera and a deviation of a roll angle of the camera on the basis of the information of the acceleration for video data stored in the memory, and performs the thinning process on the corrected video data.

11. The detecting apparatus according to claim 1,

wherein informing of an abnormal state of the person to be observed by the informing control unit of the detecting apparatus includes transmission of information indicating that the person to be observed is in an abnormal state to an external communication apparatus.

12. A detecting system for detecting a motion state of a person to be observed from a video image captured, comprising:

a camera generating video data by imaging;

a memory for storing the video data generated by the camera;

a control unit controlling a process of detecting a motion state of the person to be observed on the basis of the video data stored in the memory; and

an informing unit informing of an abnormal state of the person to be observed in the case where the control unit detects an abnormal state of the person to be observed,

wherein the control unit comprises;

a calculating unit calculating a motion vector of each of a plurality of blocks of an image including the video data;

a detecting unit extracting a block group as a set of the blocks in each of which the size of the motion vector exceeds a predetermined value on the basis of the calculated motion vectors and detecting an abnormal motion state of the person to be observed on the basis of the motion vectors of the blocks included in the extracted block group, and

an informing control unit making the informing unit perform the informing in the case where the abnormal motion state of the person to be observed is detected by the detecting unit.

13. A detecting method of a detecting system for detecting a motion state of a person to be observed from a video image captured, the detecting system comprising:

a camera generating video data by imaging;

a memory for storing the video data generated by the camera;

a processor controlling a process of detecting a motion state of the person to be observed on the basis of the video data stored in the memory; and

an informing unit,

the detecting method comprising the steps of;

calculating a motion vector of each of a plurality of blocks of an image including the video data by the processor;

extracting a block group as a set of the blocks in each of which the size of the motion vector exceeds a predetermined value on the basis of the calculated motion vectors and detecting an abnormal motion state of the person to be observed on the basis of the motion vectors of the blocks included in the extracted block group by the processor, and

making the informing unit perform the informing by the processor in the case where the abnormal motion state of the person to be observed is detected by the detecting step.