Electronic camera having multiple sensors for capturing high dynamic range images and related methods

• US 8,242,426 B2
• Filed: 12/12/2006
• Issued: 08/14/2012
• Est. Priority Date: 12/12/2006
• Status: Active Grant

• Current Assignee: Dolby Laboratories Licensing Corporation (Dolby Laboratories Incorporated)
• Original Assignee: Dolby Laboratories Licensing Corporation (Dolby Laboratories Incorporated)
• Inventors: Ward, Gregory John, Seetzen, Helge, Heidrich, Wolfgang
• Primary Examiner(s): BUI PHO, PASCAL M
• Application Number:
  US11/609,837
• Publication Number:
  US 20080149812A1
• Time in Patent Office: 2,072 Days
• Field of Search: 250/208.1, 250/216, 250/214.R, 250/214.P, 250/214.1, 348/262, 348/272, 348/281, 348/282, 348/294, 348/296, 348/302, 257/414, 257/431, 257/443, 257/451
• US Class Current: 250/208.1
• 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 23/54 Mounting of pick-up tubes, electronic image sensors, deviation or focusing coils
• CPC Class Codes: H04N 23/63 by using electronic viewfinders
• CPC Class Codes: H04N 23/70 Circuitry for compensating brightness variation in the scene
• CPC Class Codes: H04N 23/741 by increasing the dynamic range of the image compared to the dynamic range of the electronic image sensors
• CPC Class Codes: H04N 23/951 by using two or more images to influence resolution, frame rate or aspect ratio

Abstract

An electronic camera comprises two or more image sensor arrays. At least one of the image sensor arrays has a high dynamic range. The camera also comprises a shutter for selectively allowing light to reach the two or more image sensor arrays, readout circuitry for selectively reading out pixel data from the image sensor arrays, and, a controller configured to control the shutter and the readout circuitry. The controller comprises a processor and a memory having computer-readable code embodied therein which, when executed by the processor, causes the controller to open the shutter for an image capture period to allow the two or more image sensor arrays to capture pixel data, and, read out pixel data from the two or more image sensor arrays.

Claims

1. An electronic camera comprising:

two or more distinct image sensor arrays, comprising at least one low resolution image sensor array having a high dynamic range, and at least one high resolution image sensor array having a normal dynamic range smaller than the high dynamic range, such that the image sensor array having the high dynamic range is configured to capture a wider range of light intensity than the image sensor array having the normal dynamic range;

a shutter for selectively allowing light to reach the two or more image sensor arrays;

readout circuitry for selectively reading out pixel data from the image sensor arrays; and

,

a controller configured to control the shutter and the readout circuitry, the controller comprising a processor and a memory having computer-readable code embodied therein which, when executed by the processor, causes the controller to;

open the shutter for an image capture period to allow the two or more image sensor arrays to capture pixel data; and

,

read out pixel data from the two or more image sensor arrays wherein the computer-readable code, when executed by the processor, causes the controller to store the pixel data read out from the two or more image sensor arrays in a high dynamic range image data structure which specifies pixel brightness values using more than 8-bits per color.

2. A camera according to claim 1 wherein the high dynamic range data structure comprises a first portion containing high dynamic range information and a second portion containing tone map data.

3. A camera according to claim 1 wherein the computer readable code, when executed by the processor, causes the controller to combine the pixel data read out from the two or more image sensor arrays to produce high dynamic range image data.

4. A camera according to claim 3 comprising a view screen for displaying an image based on the high dynamic range image data.

5. A camera according to claim 4 wherein the view screen comprises a high dynamic range display device configured to display a high dynamic range image.

6. A camera according to claim 5 comprising a hood for shielding the high dynamic range display device.

7. A camera according to claim 1 wherein the at least one of the image sensor arrays having a high dynamic range comprises a charge coupled device specifically adapted to capture HDR pixels.

8. A camera according to claim 1 wherein the at least one low resolution image sensor array having a high dynamic range generates pixel data using at least 16 bits per pixel.

9. A camera according to claim 1, wherein the image sensor arrays are not a same image sensor array type.

10. A camera according to claim 1, wherein one of the image sensor arrays is a monochrome image sensor array and the other image sensor array is a color image sensor array.

11. A camera according to claim 1, wherein one of the image sensor arrays comprises a resolution of at least 1920×

1080.

12. A camera according to claim 1, wherein one of the image sensor arrays comprises a resolution of at least 1920×

1080 and the other image sensor array has a resolution of less than 1920×

1080.

13. A method for producing high dynamic range image data in an electronic camera comprising two or more distinct image sensor arrays, comprising at least one low resolution image sensor array having a high dynamic range and at least one high resolution image sensor array having a normal dynamic range smaller than the high dynamic range, such that the image sensor array having the high dynamic range is configured to capture a wider range of light intensity than the image sensor array having the normal dynamic range, the method comprising:

allowing light to reach the two or more image sensor arrays for an image capture period;

reading out pixel data captured by the two or more image sensor arrays during the image capture period;

combining the pixel data read out from the two or more image sensor arrays to produce high dynamic range image data; and

storing the high dynamic range image data in a memory accessible by the camera, wherein the high dynamic range image data specifies pixel brightness values using more than 8-bits per color.

14. A method according to claim 13 wherein allowing light to reach the two or more image sensor arrays for the image capture period comprises capturing multiple exposures with one of the image sensor arrays.

15. A method according to claim 14 wherein reading out pixel data captured by the two or more image sensor arrays during the image capture period comprises reading out a first exposure of the one of the image sensor arrays during the image capture period.

16. A method according to claim 13 wherein storing the high dynamic range image data in the memory comprises storing the high dynamic range image data in a data structure comprising a first portion containing high dynamic range information and a second portion containing tone map data.

17. A method according to claim 13 wherein the at least one low resolution image sensor array having a high dynamic range generates pixel data using at least 16 bits per pixel.