MULTI-AREA MONITORING SYSTEM FROM SINGLE CCTV HAVING A CAMERA QUADRATIC CURVED SURFACE MIRROR STRUCTURE AND IT, AND UNWRAPPING METHOD FOR THE SAME

• US 20100134621A1
• Filed: 04/02/2008
• Published: 06/03/2010
• Est. Priority Date: 04/06/2007
• Status: Abandoned Application

• Current Assignee: Korea Expressway Corporation (Government of South Korea)
• Original Assignee: Korea Expressway Corporation (Government of South Korea)
• Inventors: Min, Joon Young, Namkoong, Seong, Heo, Byung Do, Lee, In Jeong, Choi, Yoon Hyuk
• Application Number:
  US12/594,518
• Publication Number:
  US 20100134621A1
• Time in Patent Office: Days
• US Class Current: 348/143
• CPC Class Codes: G02B 13/06 Panoramic objectives; So-called "sky lenses" including panoramic objectives having reflecting surfaces
• CPC Class Codes: G03B 37/06 involving anamorphosis G03B37/02, G03B37/04 take precedence
• CPC Class Codes: G06T 3/12 Panospheric to cylindrical image transformations
• CPC Class Codes: H04N 23/55 Optical parts specially adapted for electronic image sensors; Mounting thereof
• CPC Class Codes: H04N 23/60 Control of cameras or camera modules
• CPC Class Codes: H04N 23/698 for achieving an enlarged field of view, e.g. panoramic image capture
• CPC Class Codes: H04N 5/2628 Alteration of picture size, shape, position or orientation, e.g. zooming, rotation, rolling, perspective, translation
• CPC Class Codes: H04N 7/183 for receiving images from a single remote source
• CPC Class Codes: Y10T 156/1052 with cutting, punching, tearing or severing

Abstract

There is provided a camera secondary curved mirror structure which is manufactured by removing a predetermined portion of a circular curved mirror for a camera which is equidistant by a predetermined distance of m/R from each side of a line which passes through the center-point of the circular curved mirror in a vertical direction, to result two curved mirror members; jointing the two curve mirror members together to form a joint line; establishing a cutting line which is perpendicular to the joint line and which is at a predetermined distance n/D from a point where the joint line intersects the circumference of the curved mirror members; and cutting along the cutting line so that a lower portion of the jointed curved mirror members results, to form a curved mirror.

Claims

1. A camera secondary curved mirror structure in a camera unit for a multi-region monitoring system picking up a bidirectional image of a road and converting the bidirectional image into an electrical image signal, comprising:

a camera secondary curved mirror mounted on the camera unit to forwardly reflect an incident bidirectional image over a long distance of the road and to collect more long-distance images than short-distance images by its inside curved mirror structure being partially removed and reconnected.

2. A method for manufacturing a camera secondary curved mirror, comprising:

a step of removing a predetermined portion of a short-distance region portion being equidistant by a predetermined distance of m/R (wherein R is a radius of the circular curved mirror) from each side of a line which passes through the center-point of the circular curved mirror in a vertical direction, and

by jointing the two curved mirror members together to form a joint line; and

a step of completing a long-distance curved mirror

by establishing a cutting line which is perpendicular to the joint line and which is at a predetermined distance n/D (wherein D is a diameter of the circular curved mirror after the predetermine portion of the short-distance region is removed) from a point where the joint line intersects the circumference of the jointed curved mirror members, and

by cutting along the cutting line so that a lower portion of the jointed curved mirror members results, to form the camera secondary curved mirror.

3. The method according to claim 2, the method further comprising a step of forming a camera aperture for receiving a camera at an inside of the secondary curved mirror and installing the camera in the camera aperture, to complete the internal camera secondary curved mirror.

4. The method according to claim 2, wherein, in the step of removing the predetermine portion of the short-distance region, when the predetermined distance is m/R, m is 1 and R is 6.

5. The method according to claim 2, wherein, in the step of completing the long-distance curved mirror, when the predetermined distance is n/D, n is 4 and D is 12.

6. The method according to claim 2, wherein, in the step of removing the predetermine portion of the short-distance region, when the predetermined distance is m/R, m is 2 and R is 10.

7. The method according to claim 5, wherein, in the step of completing the long-distance curved mirror, when the predetermined distance is n/D, n is 4 and D is 13.

8. A CCTV multi-region monitoring system having a camera secondary curved mirror structure, comprising:

a camera unit for picking up a long-distance image in all directions (360 degrees) of a road, through a camera onto which a secondary curved mirror is mounted;

an image signal processing unit for converting a long-distance image signal of a distorted optical image, which is picked up by the camera unit, into an image data; and

a computer unit for making a region of interest (ROI) by selecting an unwrapping region from the image data of the distorted image transmitted from the image signal processing unit, cropping a required curved region among the ROI, unwrapping the cropped curved region, converting the unwrapped curved image into a flat image, and displaying the flat image on a monitor.

9. The system according to claim 8, wherein the curved region set by the cropping is fan-shaped.

10. The system according to claim 8, wherein the computer unit further has a function of restoring a rough flat image to the original image, by an image calibration process.

11. The system according to claim 8, wherein, when a flat image distorted in bilateral symmetry is output by the camera of the camera unit positioned at a lower part of the secondary curved mirror, the computer unit further has a function of correcting the distorted flat image to be restored to the original image.

12. A method for correcting a distorted image in a CCTV multi-region monitoring system having a camera secondary curved mirror structure, comprising:

a step of picking up a long-distance image in all directions (360 degrees) of a road through a camera onto which a secondary curved mirror is mounted and outputting the long-distance image as an image data;

a step of setting a ROI by selecting an unwrapping region from the image data of a distorted image and making the selected region to be the ROI;

a step of performing a cropping process by overlaying the ROI over the image and cropping the ROI to generate a desired region as a curved image in a specific shape;

a step of performing an unwrapping process of the curved image of the long-distance road by the cropping process, to be converted into a flat image; and

a step of restoring a normal image by restoring a rough flat image resulting from the unwrapping process to the original image by an image calibration process, to be displayed on a monitor.

13. The method according to claim 12, wherein the curved image in a specific shape generated through the cropping process is fan-shaped.

14. The system according to claim 12, wherein the step of restoring the normal image further comprises:

a grid load step of loading various calibration grids;

a grid set step of setting a grid required for restoring the flat image, for example, a nonlinear grid, among the loaded various calibration grids;

a flat image load step of loading the unwrapped rough flat image to be calibrated; and

a calibration step of calibrating the flat image by composing the loaded rough flat image and the set grid, that is, the nonlinear grid, to output a clear flat image.

15. A method for correcting a distorted image in a CCTV multi-region monitoring a camera secondary curved mirror structure, comprising:

a step of picking up a long-distance image in all directions (360 degrees) of a road through a camera onto which a secondary curved mirror is mounted and outputting the long-distance image as an image data;

a step of making a ROI by selecting an unwrapping region from the image data of a distorted image and making the selected region to be the ROI;

a step of performing a cropping process by overlaying the ROI over the image and cropping the ROI to generate a desired region as a curved image in a specific shape;

a step of performing an unwrapping process of the curved image of the long-distance road by the cropping process, to be converted into a flat image; and

a step of restoring a normal image by restoring a rough flat image resulting from the unwrapping process to the original image by an image calibration process, and thereafter, when a flat image distorted in bilateral symmetry is output by the camera of the camera unit positioned at a lower part of the secondary curved mirror, correcting the distorted flat image to be restored to the original image, to be displayed on a monitor