IMAGING SYSTEMS AND METHODS FOR GENERATING AUTO-EXPOSED HIGH-DYNAMIC-RANGE IMAGES

• US 20130208138A1
• Filed: 01/31/2013
• Published: 08/15/2013
• Est. Priority Date: 02/09/2012
• Status: Active Grant

• Current Assignee: Semiconductor Components Industries LLC (ON Semiconductor Corporation)
• Original Assignee: Aptina Imaging Corporation (ON Semiconductor Corporation)
• Inventors: Li, Huai Dong, Lin, Peng
• Granted Patent: US 9,172,889 B2
• Time in Patent Office: Days
• US Class Current: 348/229.1
• CPC Class Codes: H04N 23/72 Combination of two or more compensation controls
• CPC Class Codes: H04N 23/73 by influencing the exposure time
• 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 25/583 with different integration times
• CPC Class Codes: H04N 25/589 with different integration times, e.g. short and long exposures

Abstract

Electronic devices may have camera modules that include an image sensor and processing circuitry. The image sensor may capture an image from a scene. The processing circuitry may extract image statistics and exposure levels from the image. The processing circuitry may use the image statistics and the exposure levels to generate a first exposure time, a second exposure time, and gain settings for the image sensor. The image sensor may capture additional images from the scene having long-exposure image pixel values that are captured using the first exposure time and short-exposure image pixel values that are captured using the second exposure time. The processing circuitry may generate a long-exposure image and a short-exposure image from the second image. The processing circuitry may generate auto-exposed high-dynamic-range images of the scene using the long-exposure image and the short-exposure image.

Claims

13. A method of using an image sensor and processing circuitry in an electronic device to generate an auto-exposed high-dynamic-range image of a scene, the method comprising:

with the image sensor, capturing image data from the scene;

with the processing circuitry, determining an auto-exposed short integration time and an auto-exposed long integration time based on the image data;

with the image sensor, capturing a first image having long-exposure image pixel values and a second image having short-exposure image pixel values, wherein the short-exposure image pixel values are captured using the auto-exposed short integration time, and wherein the long-exposure image pixel values are captured using the auto-exposed long integration time; and

with the processing circuitry, generating the auto-exposed high-dynamic-range image using the first and second images.

14-1. The method defined in claim 14, wherein determining the auto-exposed short integration time and the auto-exposed long integration time comprises:

generating image statistics from the initial long-exposure image pixel values and the initial short-exposure image pixel values.

17. A system, comprising:

a central processing unit;

memory;

input-output circuitry; and

an imaging device, wherein the imaging device comprises;

a pixel array;

a lens that focuses an image on the pixel array; and

an image sensor configured to capture image data from a scene and configured to capture long-exposure image pixel values using an auto-exposed long integration time and short-exposure image pixel values using an auto-exposed short integration time; and

processing circuitry configured to determine the auto-exposed short integration time and the auto-exposed long integration time based on the captured image data and configured to generate an auto-exposed high-dynamic-range image using the long-exposure image pixel values and the short-exposure image pixel values.

18. The system defined in claim 17, wherein the processing circuitry is further configured to generate a first interpolated image using the long-exposure image pixel values.

19. The system defined in claim 18, wherein the processing circuitry is further configured to generate a second interpolated image using the short-exposure image pixel values.

20. The system defined in claim 17, wherein the image sensor is configured to supply the image data to the processing circuitry, wherein the processing circuitry is configured to supply image sensor configuration data to the image sensor, and wherein the image sensor configuration data includes the auto-exposed long integration time and the auto-exposed short integration time.