Image feature identification and motion compensation apparatus, systems, and methods

• US 7,924,316 B2
• Filed: 03/14/2007
• Issued: 04/12/2011
• Est. Priority Date: 03/14/2007
• Status: Expired due to Fees

• Current Assignee: Aptina Imaging Corporation (ON Semiconductor Corporation)
• Original Assignee: Aptina Imaging Corporation (ON Semiconductor Corporation)
• Inventors: Li, Dong, Lin, Sheng, Silverstein, Amnon
• Primary Examiner(s): Ye; Lin
• Assistant Examiner(s): HSU, AMY R
• Application Number:
  US11/717,954
• Publication Number:
  US 20080225125A1
• Time in Patent Office: 1,490 Days
• Field of Search: 348/208.1
• US Class Current: 348/208.4
• CPC Class Codes: H04N 23/73 by influencing the exposure time

Abstract

Apparatus, systems, and methods disclosed herein may estimate the magnitude of relative motion between a scene and an image capture device used to capture the scene. Some embodiments may utilize discrete cosine transform and/or Sobel gradient techniques to identify one or more blocks of pixels in an originating calibration image frame. Matching blocks of pixels may be located in a successive calibration image frame. Motion vectors originating at one calibration frame and terminating at the other calibration frame may be calculated. The magnitude of relative motion derived thereby may be used to adjust image capture parameters associated with the image capture device, including exposure settings.

Claims

1. An apparatus, comprising:

motion priority logic to estimate a magnitude of relative motion between an entire scene and an image capture device used to capture the scene, the relative motion occurring during a time period between a time of capturing a first calibration image of the scene and a time of capturing a second calibration image of the scene, wherein the motion priority logic is configured to use the first and second calibration images of the scene to estimate the magnitude of relative motion between the entire scene and the image capture device;

final image exposure logic to calculate at least one exposure setting associated with the image capture device using the magnitude of relative motion between the entire scene and the image capture device;

an image feature selection module coupled to the motion priority logic to identify a first image feature block of pixels in the first calibration image and to store the first image feature block of pixels in an image feature buffer, wherein the image feature selection module is configured to identify the first image feature block of pixels based on an image feature strength metric value that represents a measurement of one or more characteristics other than motion that render the first image feature block of pixels distinguishable from other image features and background pixels in the first calibration image;

target matching logic coupled to the motion priority logic to search an area of the second calibration image for a second image feature block, wherein the second image feature block matches the first image feature block better than any other image feature block located within the area of the second calibration image, and wherein the area of the second calibration image corresponds to an area of the first calibration image containing the first image feature block; and

motion vector logic coupled to the motion priority logic to calculate a magnitude of a vector associated with the first image feature block as a relative distance between a location of the first image feature block and a location of the second image feature block, the relative distance divided by the time period between capturing the first calibration image and capturing the second calibration image.

2. A method, comprising:

capturing a first calibration image of a scene at a first time (T1) using an image capture device;

capturing a second calibration image of the scene at a second time (T2);

estimating a magnitude of relative motion between the entire scene and the image capture device during a period between the first time and the second time using the first calibration image and the second calibration image, wherein there is at least one object in the scene that is moving within the scene and wherein estimating the magnitude of relative motion between the entire scene and the image capture device does not include determining which object in the scene is moving the fastest relative to the scene;

adjusting an exposure setting using the magnitude of relative motion between the entire scene and the image capture device as estimated;

capturing a final image using the adjusted exposure setting; and

setting an exposure time to a value corresponding to a desired maximum amount of blur expressed as a distance divided by the magnitude of relative motion between the entire scene and the image capture device.