Focus-based shuttering

Patent metadata

Field	Value
Publication number	US-9516237-B1
Application number	US-201514842674-A
Country	US
Kind code	B1
Filing date	Sep 1, 2015
Priority date	Sep 1, 2015
Publication date	Dec 6, 2016
Grant date	Dec 6, 2016

Abstract

Blur metrics may be calculated for each of the image pixels of a digital image of a scene captured using an imaging device. The blur metrics may be indicative of the level of blur expressed in the digital image, and a blur image representative of the blur metrics may be generated. Subsequently, when another digital image is to be captured using the imaging device, pixel sensors corresponding to high blur metrics may be digitized at a high level of priority, or at a high rate, compared to pixel sensors corresponding to low blur metrics, which may be digitized at a low level of priority, or at a low rate. The blur images may be updated based on changes in blur observed in subsequent images, and different pixel sensors may be digitized at higher or lower levels of priority, or at higher or lower rates, based on the changes in blur.

First claim

What is claimed is:

1. An imaging device comprising:
an imaging sensor having a photosensitive surface with a plurality of pixel sensors;
at least one memory device; and
at least one computer processor,
wherein the at least one computer processor is configured to at least:
identify a first color image captured using the imaging sensor, wherein the first color image comprises a first plurality of image pixels;
determine a blur metric for each of the first plurality of image pixels;
define a blur image based at least in part on the blur metrics of the first plurality of image pixels;
define a plurality of regions of image pixels within the blur image, wherein each of the regions comprises image pixels having a substantially similar blur metric;
select a first region of the plurality of regions of image pixels of the blur image, the first region comprising image pixels having blur metrics higher than other regions of the plurality of regions;
identify a first subset of the plurality of pixel sensors of the photosensitive surface corresponding to the first region of the blur image;
expose the first subset of the plurality of pixel sensors to light for a first predetermined period of time;
digitize a first set of signals generated in response to the exposure of the first subset of the pixel sensors to light for the first predetermined period of time; and
store a second color image comprising the digitized first set of signals in the at least one memory device.

2. The imaging device of claim 1 , wherein the at least one computer processor is further configured to at least:
determine the first predetermined period of time based at least in part on the blur metrics of the image pixels of the first region of the blur image.

3. The imaging device of claim 1 , wherein the at least one computer processor is further configured to at least:
select a second region of the plurality of regions of image pixels of the blur image;
identify a second subset of the plurality of pixel sensors of the photosensitive surface corresponding to the second region of the blur image;
expose the second subset of the plurality of pixel sensors to light for a second predetermined period of time; and
digitize a second set of signals generated in response to the exposure of the second subset of the pixel sensors to light for the second predetermined period of time,
wherein the second color image further comprises the digitized second set of signals.

4. The imaging device of claim 3 , wherein the at least one computer processor is further configured to at least:
determine a first frequency for digitizing signals generated in response to exposure of the first subset of the plurality of pixel sensors to light; and
determine a second frequency for digitizing signals generated in response to the exposure of the second subset of the plurality of pixel sensors to light,
wherein the first set of signals generated in response to the exposure of the first subset of the pixel sensors to light for the first predetermined period of time are digitized in accordance with the first frequency, and
wherein the second set of signals generated in response to the exposure of the second subset of the pixel sensors to light for the second predetermined period of time are digitized in accordance with the second frequency.

5. The imaging device of claim 1 , wherein the at least one computer processor is further configured to at least:
provide information regarding the first color image as an input to at least one of a Laplacian operator, a Sobel operator or a Tenengrad operator; and
determine the blur metric for each of the first plurality of image pixels based at least in part on an output from the Laplacian operator, the Sobel operator or the Tenengrad operator.

6. A computer-implemented method comprising:
identifying a first digital image captured using a first imaging device, wherein the first digital image comprises a first plurality of image pixels, and wherein the first imaging device comprises a data store and a photosensitive surface having an array of pixel sensors;
determining a first blur metric for each of the first plurality of image pixels of the first digital image;
identifying a first subset of the first plurality of image pixels, wherein each of the image pixels of the first subset has a substantially similar first blur metric;
selecting a first subset of the array of pixel sensors corresponding to the first subset of the first plurality of image pixels, wherein the first subset of the array of pixel sensors is selected based at least in part on the substantially similar first blur metric of the first subset of the first plurality of image pixels;
exposing at least the first subset of the array of pixel sensors to light for a first predetermined period of time;
converting a first set of analog signals to a second plurality of image pixels, wherein each of the first set of analog signals is generated in response to the exposure of the first subset of the array of pixel sensors to light; and
storing a second digital image comprising the second plurality of image pixels in the data store.

7. The computer-implemented method of claim 6 , further comprising:
after converting the first set of analog signals to the second plurality of image pixels, converting a second set of analog signals to a third plurality of image pixels,
wherein each of the second set of analog signals is generated in response to the exposure of a second subset of the array of pixel sensors to light,
wherein the second digital image comprises the second plurality of image pixels and the third plurality of image pixels.

8. The computer-implemented method of claim 6 , further comprising:
generating a blur image based at least in part on the first blur metric for each of the first plurality of image pixels of the first digital image; and
storing the blur image in the data store.

9. The computer-implemented method of claim 8 , wherein identifying the first subset of the first plurality of image pixels further comprises:
defining a plurality of subsets of the first plurality of image pixels of the first digital image based at least in part on the blur image, wherein each of the subsets of the first plurality of image pixels of the first digital image comprises image pixels having a substantially similar first blur metric, and wherein the first subset of the first plurality of image pixels is one of the plurality of subsets of the first plurality of image pixels of the first digital image.

10. The computer-implemented method of claim 9 , wherein the first subset of the array of pixel sensors is selected based at least in part on the blur image.

11. The computer-implemented method of claim 9 , further comprising:
determining a ranking of at least some of the plurality of subsets of the first plurality of image pixels of the first digital image based at least in part on the blur image; and
defining a digitization priority for the at least some of the plurality of subsets based at least in part on the ranking,
wherein the first subset of the array of pixel sensors is selected based at least in part on the digitization priority.

12. The computer-implemented method of claim 8 , further comprising:
determining a second blur metric for each of the second plurality of image pixels of the second digital image; and
updating the blur image based at least in part on the second blur metrics for each of the second plurality of image pixels of the second digital image,
wherein the first subset of the array of pixel sensors is selected based at least in part on a difference between the first blur metrics and the s

Assignees

• Amazon Tech Inc

Inventors

• Goyal Dushyant
• Mishra Pragyana K

Classifications

• H04N23/67 Primary

  Focus control based on electronic image sensor signals · CPC title

• H04N23/73

  by influencing the exposure time · CPC title

• H04N9/045

  Electricity · mapped topic

• H04N5/23212

  Electricity · mapped topic

• G06K2009/4666

  Physics · mapped topic