Video monitoring method, video monitoring system and computer program product

1. A video monitoring method comprising:

obtaining video data collected by a video collecting apparatus;

determining an object as a monitoring target based on the video data; and

extracting feature information of the object,

wherein the video data is video data containing depth information, and

wherein determining the object as the monitoring target based on the video data comprises:

determining background information in the video data;

determining foreground information in each frame of the video data based on the background information;

obtaining edge profile information of a foreground area corresponding to the foreground information;

obtaining a candidate block based on the edge profile information;

determining the candidate block larger than a first predetermined threshold as a candidate object;

obtaining an evaluation value of the candidate object based on a predetermined algorithm; and

determining the candidate object whose evaluation value is larger than a second predetermined threshold as the object.

2. The video monitoring method according to claim 1 , further comprising:

configuring the video collecting apparatus and determining coordinate parameters of the video collecting apparatus.

3. The video monitoring method according to claim 2 , wherein determining coordinate parameters of the video collecting apparatus comprise:

selecting multiple reference points on a predetermined reference plane;

determining transformation relationship between a camera coordinate system of the video collecting apparatus and a world coordinate system based on coordinate information of the multiple reference points; and

determining the coordinate parameters of the video collecting apparatus based on the transformation relationship.

4. The video monitoring method according to claim 1 , further comprising:

matching each object determined in the previous frame with each object determined in current frame to determine an object that left the previous frame.

5. The video monitoring method according to claim 1 , wherein the feature information of the object comprises bodily form information and motion speed of the object.

6. The video monitoring method according to claim 5 , wherein extracting the bodily form information of the object comprises:

selecting the nearest point of the object to the video collecting apparatus as a head point of the object;

determining coordinate parameters of the head point in the world coordinate system based on the transformation relationship between the camera coordinate system of the video collecting apparatus and the world coordinate system; and

determining the distance between the head point of the object and the ground as height information of the object based on the coordinate parameter of the head point in the world coordinate system.

7. The video monitoring method according to claim 5 , wherein extracting the bodily form information of the object comprises:

selecting the nearest point of the object to the video collecting apparatus as a head point of the object;

selecting a point of the object with the largest value in an ordinate of an image coordinate system as a sole point of the object; and

determining the distance between the head point of the object and the sole point of the object in the world coordinate system as height information of the object based on the transformation relationship between the camera coordinate system of the video collecting apparatus and the world coordinate system.

8. The video monitoring method according to claim 5 , further comprising:

calculating a motion distance of a first fixed point of the object between a first selected frame and a second selected frame in the world coordinate system;

determining the motion speed of the object based on the time interval between the first selected frame and the second selected frame and the motion distance.

9. The video monitoring method according to claim 5 , wherein extracting the bodily form information of the object further comprises:

extracting height information and profile information of the object;

determining weight information of the object according to the height information and the profile information of the object based on correspondence relationship among height information, profile information and weight information of various objects collected in advance.

10. The video monitoring method according to claim 5 , further comprising:

analyzing the feature information and determining an abnormal event of the object,

wherein analyzing the feature information and determining an abnormal event of the object comprises

determining the abnormal event of the object when the variation of the bodily form information in a predetermined period of time is larger than a predetermined third threshold and/or when the motion speed of the object is larger than a fourth threshold.

11. A video monitoring system comprising:

a processor;

a memory; and

computer program instructions stored in the memory, which, when executed by the processor, perform the steps of:

obtaining video data collected by a video collecting apparatus;

determining an object as a monitoring target based on the video data; and

extracting feature information of the object,

wherein the video data is video data containing depth information, and

wherein the step of determining the object as the monitoring target based on the video data performed by the computer program instructions when executed by the processor comprises:

determining background information in the video data;

determining foreground information in each frame of the video data based on the background information;

obtaining edge profile information of a foreground area corresponding to the foreground information;

obtaining a candidate block based on the edge profile information;

determining the candidate block larger than a first predetermined threshold as a candidate object;

obtaining an evaluation value of the candidate object based on a predetermined algorithm; and

determining the candidate object whose evaluation value is larger than a second predetermined threshold as the object.

12. The video monitoring system according to claim 11 , further comprising the video collecting apparatus for collecting the video data.

13. The video monitoring system according to claim 12 , wherein the computer program instructions, when executed by the processor, further perform the steps of:

selecting multiple reference points on a predetermined reference plane;

determining transformation relationship between a camera coordinate system of the video collecting apparatus and a world coordinate system based on coordinate information of the multiple reference points; and

determining the coordinate parameters of the video collecting apparatus based on the transformation relationship.

14. The video monitoring system according to claim 11 , wherein when executed by the processor, the computer program instructions further perform the step of:

matching each object determined in the previous frame with each object determined in current frame to determine an object that left the previous frame.

15. The video monitoring system according to claim 11 , wherein the feature information of the object comprises bodily form information and motion speed of the object.

16. The video monitoring system according to claim 15 , wherein the step of extracting the bodily form information of the object performed by the computer program instructions when executed by the processor comprises:

selecting the nearest point of the object to the video collecting apparatus as a head point of the object;

determining coordinate parameters of the head point in the world coordinate system based on the transformation relationship between the camera coordinate system of the video collecting apparatus and the world coordinate system; and

determining the distance between the head point of the object and the ground as height information of the object based on the coordinate parameter of the head point in the world coordinate system.

17. The video monitoring system according to claim 15 , wherein the step of extracting the bodily form information of the object performed by the computer program instructions when executed by the processor comprises:

selecting the nearest point of the object to the video collecting apparatus as a head point of the object;

selecting a point of the object with the largest value in an ordinate of an image coordinate system as a sole point of the object; and

determining the distance between the head point of the object and the sole point of the object in the world coordinate system as height information of the object based on the transformation relationship between the camera coordinate system of the video collecting apparatus and the world coordinate system.

18. The video monitoring system according to claim 15 , the step of extracting the feature information of the object performed by the computer program instructions when executed by the processor further comprises:

calculating a motion distance of a first fixed point of the object between a first selected frame and a second selected frame in the world coordinate system;

determining the motion speed of the object based on the time interval between the first selected frame and the second selected frame and the motion distance.

19. The video monitoring system according to claim 15 , wherein the step of extracting the bodily form information of the object performed by the computer program instructions when executed by the processor further comprises:

extracting height information and profile information of the object;

determining weight information of the object according to the height information and the profile information of the object based on correspondence relationship among height information, profile information and weight information of various objects collected in advance.

20. The video monitoring system according to claim 15 , wherein the computer program instructions, when executed by the processor, further perform the steps of:

analyzing the feature information and determining an abnormal event of the object, and the step of determining an abnormal event of the object performed by the computer program instructions when executed by the processor comprises:

determining the abnormal event of the object when the variation of the bodily form information in a predetermined period of time is larger than a predetermined third threshold and/or when the motion speed of the object is larger than a fourth threshold.

21. A non-transitory computer program product comprising a computer readable storage medium on which computer program instructions are stored, wherein the computer program instructions, when executed by the processor, perform the steps of:

obtaining video data collected by a video collecting apparatus;

determining an object as a monitoring target based on the video data; and

extracting feature information of the object,

wherein the video data is video data containing depth information, and

wherein the step of determining the object as the monitoring target based on the video data performed by the computer program instructions when executed by the processor comprises:

determining background information in the video data;

determining foreground information in each frame of the video data based on the background information;

obtaining edge profile information of a foreground area corresponding to the foreground information;

obtaining a candidate block based on the edge profile information;

determining the candidate block larger than a first predetermined threshold as a candidate object;

obtaining an evaluation value of the candidate object based on a predetermined algorithm; and

determining the candidate object whose evaluation value is larger than a second predetermined threshold as the object.