Camera with an image sensor that doubles as a motion sensor

• US 8,619,149 B2
• Filed: 09/11/2006
• Issued: 12/31/2013
• Est. Priority Date: 09/11/2006
• Status: Active Grant

• Current Assignee: PixArt Imaging Incorporated
• Original Assignee: Avago Technologies General IP PTE Limited (Broadcom, Inc.)
• Inventors: Xie, Tong
• Primary Examiner(s): AGGARWAL, YOGESH K
• Application Number:
  US11/518,962
• Publication Number:
  US 20080062285A1
• Time in Patent Office: 2,668 Days
• Field of Search: 348/222.1, 348/220.1, 348/240.1, 348/335, 348/340, 348/345, 348/348, 348/350, 348/352
• US Class Current: 348/222.1
• CPC Class Codes: H04N 23/68 for stable pick-up of the scene, e.g. compensating for camera body vibrations
• CPC Class Codes: H04N 23/6811 based on the image signal
• CPC Class Codes: H04N 23/683 performed by a processor, e.g. controlling the readout of an image memory

Abstract

A camera includes an image sensor that doubles as a motion sensor. An image sensor in a camera according to the present teachings generates a digital image by sampling light from an image scene and also generates a series of motion frames that enable a determination of a camera motion.

Claims

1. A camera, the camera comprising:

an image sensor configured to generate a digital image for display to a user by sampling light from an image scene during a sample time T, the image sensor further configured to generate a series of N number of motion frames that enable a determination of a camera motion that occurs during acquisition of the digital image, wherein the N number of motion frames are generated during each of a series of N number of sub-intervals of sample time T, wherein the image sensor generates the motion frames by scanning out a set of pixel values contained in a sub-region of the image sensor, wherein dimensions of the sub-region are smaller than dimensions of the digital image displayed to the user;

an image processor configured to receive the motion frames from the image sensor and to determine camera motion in response to the motion frames; and

a user interface that enables a user of the camera to select the sub-region prior to the image sensor generating the digital image.

2. The camera of claim 1, wherein the dimensions of the sub-region are selected based, at least in part, on one or more of (i) sample time T, (ii) a user selection, (iii) a desired quality of motion detection, and (iv) a size of an autofocus region of the image sensor.

3. The camera of claim 1, further comprising shutter mechanism configured to enable the image sensor to acquire the digital image during a sample time T and the motion frames during sub-intervals of the sample time T.

4. The camera of claim 1, wherein the image processor generates a blur corrected digital image in response to the digital image and the motion frames.

5. The camera of claim 1, wherein the image processor is further configured to generate an image frame that carries the digital image and a set of information that enables a determination of the camera motion associated the digital image.

6. The camera of claim 5, further comprising an input/output circuit for transferring the image frame to a remote system.

7. The camera of claim 5, wherein the information includes the motion frames.

8. The camera of claim 5, wherein the information includes a set of motion vectors derived from the motion frames by the image processor.

9. The camera of claim 1, wherein a number of pixels in the sub-region is less than or equal to about 3600 pixels.

10. A method for using an image sensor in a camera as a motion sensor for the camera, the method comprising:

generating a digital image with the image sensor during a time t=N;

generating a series of motion frames with the image sensor during a sample period T between time t=0 and t=N;

scanning out a digital image from the image sensor with a read circuit;

scanning out a series of motion frames from the image sensor, wherein the series of motion frames are sequentially generated by the image sensor and scanned out of the image sensor by the read circuit during each of the N sub-intervals of the sample period T while the digital image is being generated by the image sensor, wherein scanning out a series of motion frames comprises scanning out a set of pixel values contained in a sub-region of the image sensor wherein a number of pixels in the sub-region is less than a number of pixels in the digital image, and wherein the number of pixels in the sub-region is less than about 0.002% of the number of pixels in the image sensor;

controlling sample period T with a shutter mechanism; and

utilizing the motion frames obtained from the sub-region to determine camera motion.

11. The method of claim 10, further comprising selecting the sub-region.

12. The method of claim 10, wherein scanning out a series of motion frames comprises scanning out a set of pixel values contained in an auto-focus region of the image sensor.

13. The method of claim 10, further comprising determining the camera motion in response to the motion frames with an image processor in the camera.

14. The method of claim 13, further comprising the image processor in the camera generating a blur corrected digital image in response to the digital image and the motion frames.

15. The method of claim 10, further comprising an image processor in the camera generating an image frame that carries the digital image and a set of information that enables a determination of the camera motion associated the digital image.

16. The method of claim 15, further comprising transferring the image frame to a remote system.

17. A method for using an image sensor in a camera as a motion sensor for the camera, the method comprising;

generating a digital image with the image sensor during a time t=N;

generating a series of motion frames with the image sensor during a sample period T between time t=0 and t=N;

scanning out a digital image from the image sensor with a read circuit;

scanning out a series of motion frames from the image sensor, wherein the series of motion frames are sequentially generated by the image sensor and scanned out of the image sensor by the read circuit during each of the N sub-intervals of the sample period T while the digital image is being generated by the image sensor, wherein scanning out a series of motion frames comprises scanning out a set of pixels values contained in a sub-region of the image sensor and wherein a number of pixels in the sub-region is less than a number of pixels in the digital image;

controlling sample period T with a shutter mechanism;

utilizing the motion frames obtained from the sub-region to determine camera motion; and

generating an image frame that carries the digital image and a set of information that enables a determination of the camera motion associated the digital image, wherein generating an image frame comprises generating the image frame with the motion frames in a header.

18. A method for using an image sensor in a camera as a motion sensor for the camera, the method comprising;

generating a digital image sensor during a time t=N;

generating a series of motion frames with the image sensor during a sample period T between time t=0 and t=N;

scanning out a digital image from the image sensor with a read circuit;

scanning out a series of motion frames from the image sensor, wherein the series of motion frames are sequentially generated by the image sensor and scanned out of the image sensor by the read circuit during each of the N sub-intervals of the sample period T while the digital image is being generated by the image sensor, wherein scanning out a series of motion frames comprises scanning out a set of pixel values contained in a sub-region of the image sensor and wherein a number of pixels in the sub-region is less than a number of pixels in the digital image;

controlling sample period T with a shutter mechanism;

utilizing the motion frames obtained from the sub-region to determine camera motion; and

generating an image frame that carries the digital image and a set of information that enables a determination of the camera motion associated the digital image, wherein generating an image frame comprises generating the image frame with a set of motion vectors derived from the motion frames in a header.