Systems and methods of creating a virtual window

• US 20090147071A1
• Filed: 11/17/2008
• Published: 06/11/2009
• Est. Priority Date: 11/16/2007
• Status: Active Grant

• Current Assignee: Blackhawk Imaging LLC
• Original Assignee: Tenebraex Corporation
• Inventors: Jones, Peter W.J., Purcell, Dennis W.
• Granted Patent: US 8,564,640 B2
• Time in Patent Office: Days
• US Class Current: 348/36
• CPC Class Codes: G08B 13/19693 using multiple video sources viewed on a single or compound screen
• CPC Class Codes: H04N 23/45 for generating image signals from two or more image sensors being of different type or operating in different modes, e.g. with a CMOS sensor for moving images in combination with a charge-coupled device [CCD] for still images
• CPC Class Codes: H04N 23/698 for achieving an enlarged field of view, e.g. panoramic image capture
• CPC Class Codes: H04N 23/70 Circuitry for compensating brightness variation in the scene
• CPC Class Codes: H04N 23/951 by using two or more images to influence resolution, frame rate or aspect ratio
• CPC Class Codes: H04N 5/262 Studio circuits, e.g. for mixing, switching-over, change of character of image, other special effects ; Cameras specially adapted for the electronic generation of special effects
• CPC Class Codes: H04N 5/2624 for obtaining an image which is composed of whole input images, e.g. splitscreen

Abstract

The systems and methods described provide an imaging system that allows multiple sensors to record images at their respective best exposures values and adaptively altering the exposure of the images recorded to create a seamless 360-degree view. In particular, the systems and methods described herein include determining exposure values for each column of photosensitive elements in a sensor by interpolating between the best exposure values of adjacent sensors.

Claims

1. A method of imaging a scene, comprising

disposing a first imaging sensor adjacent to a second imaging sensor, each sensor having an array of photosensitive elements for recording a charge in response to incident light;

determining a first exposure value for the first sensor and a second exposure value for the second sensor;

receiving light from the scene at the first and second sensors;

transferring charge collected at each of the photosensitive elements in the first and second sensors to a processor;

modifying the charge collected at one or more of the photosensitive elements based on first and second exposure value; and

generating an image of the scene based on the modified charge.

2. The method of claim 1, wherein the first imaging sensor is disposed horizontally adjacent to the second imaging sensor.

3. The method of claim 2, wherein charge collected at each of the photosensitive elements in the first sensor are transferred column-wise to a processor beginning with a border column nearest the second sensor.

4. The method of claim 2, wherein charge collected at each of the photosensitive elements in the second sensor are transferred column-wise to a processor beginning with a border column nearest the first sensor.

5. The method of claim 1, wherein the first imaging sensor is disposed vertically adjacent to the second imaging sensor.

6. The method of claim 1, wherein modifying the charge includes determining interpolated exposure values for each column of photosensitive elements in the first and second sensor based on the first and second exposure value, and modifying the charge based on the interpolated exposure values.

7. The method of claim 1, wherein modifying the charge includes generating a signal value based on the charges from the first and second sensors and modifying the signal value based on the first and second exposure value.

8. The method of claim 7, wherein modifying the signal value includes determining an interpolated exposure value based on the first and second exposure value, and modifying the signal value corresponding to each column based on the interpolated exposure value.

9. The method of claim 8, wherein determining the interpolated exposure value includes performing at least one of a linear, spline and cubic interpolation between the first exposure value and the second exposure value.

10. An imaging system, comprising

a first imaging sensor having a plurality of photosensitive elements;

a second imaging sensor having a plurality of photosensitive elements and disposed adjacent to the first imaging sensor;

an exposure circuitry for determining a first exposure value for the first imaging sensor and a second exposure value for the second imaging sensor; and

a processor configured with circuitry, for

modifying the charge collected at one or more of the photosensitive elements based on first and second exposure value, and

generating an image of the scene based on the modified charge.

11. The imaging system of claim 10, further comprising a plurality of imaging sensors, each disposed adjacent to one another.

12. The imaging system of claim 11, wherein the plurality of imaging sensors and the first and second imaging sensors are positioned in a closed circle having a combined field-of-view of about 360 degrees.

13. The imaging system of claim 11, wherein the plurality of imaging sensors and the first and second imaging sensors are positioned in a semi-circle having a combined field-of-view of about 180 degrees.

14. The imaging system of claim 10, wherein at least one of the first and second imaging sensor includes a charge-coupled device (CCD) imaging sensor.

15. The imaging system of claim 14, wherein the first and the second imaging sensor are positioned horizontally adjacent to one another.

16. The imaging system of claim 15, wherein the first and second imaging sensors are oriented such that charges from the first and second sensors are transferred along vertical columns beginning with columns nearest the other one of the sensors.

17. The imaging system of claim 10, wherein at least one of the first and second imaging sensor includes a complimentary metal-oxide semiconductor (CMOS) imaging sensor.

18. A method of generating a digital image of a scene, comprising

disposing a first charge-coupled device image sensor adjacent to a second charge-coupled device image sensor, each sensor having rows and columns of photosensitive elements, such that the first sensor borders the second sensor along a direction parallel to the columns of each sensor;

recording an image using the sensors, including the steps of

exposing, at a first exposure value, the first sensor to light from the scene,

exposing, at a second exposure value, the second sensor to light from the scene, and

determining an interpolated exposure value for the photosensitive elements in each column of each sensor based on the first and second exposure values, and

generating a signal value by transferring charge accumulated at the photosensitive elements in each sensor, column-wise to an output amplifier;

modifying the signal value for each column based on the interpolated exposure value; and

generating an image based corresponding to the scene based on the modified signal value.

19. The method of claim 18, wherein transferring charge column-wise includes

transferring, to a processor, charge from photosensitive elements in a border column on the first sensor nearest to the second sensor, and charge from photosensitive elements in a border column on the second sensor nearest to the first sensor;

transferring, to the processor, charge from the remaining columns in the first sensor sequentially away from the border column on the first sensor; and

transferring, to the processor, charge from the remaining columns in the second sensor sequentially away from the border column on the second sensor;

20. The method of claim 18, wherein an interpolated exposure value of the column in the first sensor, nearest to the second sensor is substantially the same as an interpolated exposure value of the column in the second sensor, nearest to the first sensor.

21. The method of claim 18, wherein one or more interpolated exposure values are calculated based on a linear interpolation between the first and second exposure values.

22. The methods of claim 18, wherein one or more interpolated exposure values are calculated based on a spline interpolation between the first and second exposure values.

23. The method of claim 18, wherein at least one column in the first sensor has an exposure value equal to the first exposure value and at least one column in the second sensor has an exposure value equal to the second exposure value.

24. The method of claim 18, further comprising disposing one or more additional charge-coupled device imaging sensors adjacent to at least one of the first and second sensor.

25. The method of claim 24, wherein recording the image includes exposing the one or more additional sensor at an third exposure value and determining interpolated exposure values for columns between the one or more additional sensors and the first and second sensors based on the first, second and third exposure values.

26. An imaging system, comprising

a first charge-coupled device imaging sensor positioned adjacent to a second charge-coupled device imaging sensor, each sensor having rows and columns of photosensitive elements;

exposure circuitry connected to the first and second sensor and configured to determine a first exposure value for the first sensor and a second exposure value for the second sensor; and

a processor, for receiving a charge from each of the photosensitive elements in the first and second sensors, and having circuitry configured for

calculating interpolated exposure values for each column of photosensitive elements on each sensor based on the first and second exposure value,

receiving charges from photosensitive elements in each sensor along a first column nearest to the other one of the sensors,

receiving charges from the photosensitive elements in remaining columns in each sensor along a direction away from the other sensor,

modifying the received charges based on the interpolated exposure values, and

generating an image based on the modified charge.