Surveillance system and surveillance method thereof

• US 8,248,469 B2
• Filed: 03/18/2009
• Issued: 08/21/2012
• Est. Priority Date: 08/08/2008
• Status: Expired due to Fees

• Current Assignee: Hon Hai Precision Industry Co., Ltd.
• Original Assignee: Hon Hai Precision Industry Co., Ltd.
• Inventors: Lee, Shiao-Wei
• Primary Examiner(s): Backer, Firmin
• Assistant Examiner(s): Bui, Jonathan
• Application Number:
  US12/406,923
• Publication Number:
  US 20100033568A1
• Time in Patent Office: 1,252 Days
• Field of Search: 348/143, 382/103, 382/107
• US Class Current: 348/143
• CPC Class Codes: G08B 13/1961 Movement detection not involving frame subtraction, e.g. motion detection on the basis of luminance changes in the image
• CPC Class Codes: H04N 7/183 for receiving images from a single remote source

Abstract

A method for surveillance is disclosed. Firstly, video of an area is captured. The video includes a first image and a second. Each image is subdivided into a number of subdivisions. A contrast value matrix is then calculated for each image by calculating a contrast value for each subdivision. A compared value matrix of the second image is calculated by comparing each element of the contrast value matrix associated with the current image with a corresponding element of the contrast value matrix associated with the prior image. Next, the compared value matrix is weighted using a preset weight matrix to locate the movement in the second image. Finally, the aim of capturing is adjusted based upon the location of movement.

Claims

1. A surveillance system comprising:

a video capturing unit capable of capturing video of an area, the video comprises a prior image and a current image;

a detecting unit configured for subdividing each of the prior and current images into a plurality of subdivisions and calculating a contrast value for each subdivision to produce a contrast value matrix associated with each of the prior and current images;

a comparing unit configured for comparing each element of the contrast value matrix associated with the current image with a corresponding element of the contrast value matrix associated with the prior image and determining a compared value matrix associated with the current image;

a calculating unit configured for weighting the compared value matrix using a preset weight value matrix to determine a location of a moving object in the current image; and

a controlling unit configured for adjusting the aim of the video capturing unit to keep the moving object included in a subsequent image of the video based upon the determination of the calculating unit;

wherein the detecting unit counts the number of pixels whose values are greater than a predetermined value for each subdivision, and calculates the ratio of the total number of pixels to the counted number for each subdivision, the calculated ratios are the contrast values of the subdivisions.

2. The surveillance system as claimed in claim 1, wherein the video capturing unit comprises a lens and an image sensor.

3. The surveillance system as claimed in claim 2, where in the image sensor is selected from the group consisting of a charge-coupled device and a complementary metal oxide semiconductor.

4. The surveillance system as claimed in claim 1, wherein an element of the comparing value matrix is valued as ‘

0’

if the difference between two corresponding compared elements is smaller than a predetermined threshold and otherwise is valued as ‘

1’

.

5. The surveillance system as claimed in claim 1, wherein the preset weight value matrix is:

6. A surveillance method comprising:

capturing video of an area, the video comprises a prior image and a current image;

subdividing each of the prior and current images into a plurality of subdivisions and calculating a contrast value for each subdivision;

producing a contrast value matrix for each of the prior and current images;

comparing each element of the contrast value matrix of the current image with a corresponding element of the contrast value matrix of the prior image and thereby determining a compared value matrix associated with the current image;

weighting the compared value matrix using a preset weight matrix to determine where a moving object is located in the current image; and

adjusting the aim of the capturing to include the moving object in a subsequent image of the video based upon the determination in the weighting step;

wherein the number of pixels whose values are greater than a predetermined value for each subdivision is counted, and the ratio of the total number of pixels to the counted number for each subdivision is calculated, and the calculated ratio is the contrast value for each subdivision.

7. A surveillance method comprising:

providing a surveillance system comprising;

a video capturing unit capable of capturing video of an area, the video comprises a prior image and a current image;

a detecting unit configured for subdividing each of the prior and current images into a plurality of subdivisions and calculating a contrast value for each subdivision to produce a contrast value matrix associated with each of the prior and current images;

a comparing unit configured for comparing each element of the contrast value matrix associated with the current image with a corresponding element of the contrast value matrix associated with the prior image and determining a compared value matrix associated with the current image;

a calculating unit configured for weighting the compared value matrix using a preset weight value matrix to determine a location of a moving object in the current image; and

a controlling unit configured for adjusting the aim of the video capturing unit to keep the moving object included in a subsequent image of the video based upon the determination of the calculating unit;

capturing the video of the area using the video capturing unit;

subdividing each image into a plurality of subdivisions and calculating the contrast value for each subdivision using the detecting unit;

producing the contrast value matrix for each of the prior and current image using the detecting unit;

comparing each element of the contrast value matrix of the current image with a corresponding element of the contrast value matrix of the prior image and thereby determining the compared value matrix associated with the current image;

weighting the compared value matrix using the preset weight matrix to determine where the moving object is located in the current image using the calculating unit; and

adjusting the aim of the capturing to include the moving object in the subsequent image of the video based upon the determination of the calculating unit using the controlling unit;

wherein the number of pixels whose values are greater than a predetermined value for each subdivision is counted, and the ratio of the total number of pixels to the counted number for each subdivision is calculated, and the calculated ratio is the contrast value for each subdivision.