Automated extended depth of field imaging apparatus and method

• US 10,154,203 B2
• Filed: 04/11/2016
• Issued: 12/11/2018
• Est. Priority Date: 03/05/2008
• Status: Active Grant

• Current Assignee: Applied Minds LLC
• Original Assignee: Applied Minds LLC
• Inventors: Ferren, Bran
• Primary Examiner(s): Aggarwal, Yogesh
• Application Number:
  US15/095,597
• Publication Number:
  US 20160227094A1
• Time in Patent Office: 974 Days
• Field of Search: 348335, 348340, 348345, 348348, 348350, 348352
• CPC Class Codes: G03B 13/36 Autofocus systems
• CPC Class Codes: H04N 23/62 Control of parameters via user interfaces
• CPC Class Codes: H04N 23/64 Computer-aided capture of images, e.g. transfer from script file into camera, check of taken image quality, advice or proposal for image composition or decision on when to take image
• CPC Class Codes: H04N 23/743 Bracketing, i.e. taking a series of images with varying exposure conditions
• CPC Class Codes: H04N 23/951 by using two or more images to influence resolution, frame rate or aspect ratio
• CPC Class Codes: H04N 23/959 by adjusting depth of field during image capture, e.g. maximising or setting range based on scene characteristics
• CPC Class Codes: H04N 5/2625 for obtaining an image which is composed of images from a temporal image sequence, e.g. for a stroboscopic effect sequence generated by event triggered capturing H04N7/188

Abstract

An imaging apparatus and method enables an automated extended depth of field capability that automates and simplifies the process of creating extended depth of field images. An embodiment automates the acquisition of an image “stack” or sequence and stores metadata at the time of image acquisition that facilitates production of a composite image having an extended depth of field from at least a portion of the images in the acquired sequence. An embodiment allows a user to specify, either at the time of image capture or at the time the composite image is created, a range of distances that the user wishes to have in focus within the composite image. An embodiment provides an on-board capability to produce a composite, extended depth of field image from the image stack. One embodiment allows the user to import the image stack into an image-processing software application that produces the composite image.

Claims

1. A method, comprising:

receiving, at an imaging apparatus, a range of distances external to the imaging apparatus to be in focus for a composite, extended depth-of-field image, wherein the received range of distances are acquired based on a range finding of two or more points of interest;

estimating, at the imaging apparatus, a hyperfocal distance of the imaging apparatus based on features of the imaging apparatus;

iteratively calculating, at the imaging apparatus, a range of focus distances based on the received range of distances and the estimated hyperfocal distance;

acquiring a stack of images with the imaging apparatus by capturing at least one image at each calculated focus distance of the range of focus distances; and

creating the composite, extended depth-of-field image based on the stack of images acquired with the imaging apparatus.

2. The method of claim 1, wherein the received range of distances includes near and far limits specified by an autofocus feature of the imaging apparatus.

3. The method of claim 1, wherein the two or more points of interest are determined by an object detection process.

4. The method of claim 1, wherein the imaging apparatus includes any of a digital camera or a film camera.

5. The method of claim 1, further comprising:

creating the composite, extended depth-of-field image from at least a portion of the stack of images.

6. The method of claim 1, further comprising:

inputting a user specification to have exactly the received range of distances in focus during imaging.

7. The method of claim 6, further comprising:

automatically adjusting a focus distance of a terminal image in the received range of distances so that a depth of field limit for the terminal image corresponds to a specified limit of the received range of distances.

8. The method of claim 1, wherein said acquiring the stack of images is performed by a processor upon activation of a control element.

9. A device, comprising:

an imaging apparatus;

a range finder that enables specification of a range of distances external to the imaging apparatus to be in focus for a composite-depth-of-field image; and

a processor operably coupled to memory that stores executable instructions which when executed by the processor causes the imaging apparatus to;

receive the specified range of distances,

estimate a hyperfocal distance,

iteratively calculate a range of focus distances based on the received specified range of distances and the estimated hyperfocal distance,

capture at least one image at each calculated focus distance of the range of focus distances, and

create the composite-depth-of-field image based on the captured images captured at the calculated focus distances.

10. The device of claim 9, wherein the range finder is a spot-metering range finder and the specified range of distances includes near and far limits specified by the range finder.

11. The device of claim 9, further comprising:

a user interface configured to receive a specification of distance ranges by a user.

12. The device of claim 9, wherein the imaging apparatus includes any of a digital camera or a film camera.

13. The device of claim 9, wherein the memory further includes instructions, which when executed by the processor, causes the processor to create the composite-depth-of-field image from at least a portion of the stack of images.

14. The device of claim 11, wherein the user interface includes manual dials.

15. The device of claim 14, wherein the memory further includes instructions for adjusting a focus distance of an image to be captured based on the received range of distances so that a depth of field limit for the image corresponds to a specified limit of the received range of distances.

16. A non-transitory computer readable medium including instructions for performing, wherein executed by a processor, steps comprising:

receiving a range of distances external to an imaging apparatus to be in focus for a composite, extended depth-of-field image;

estimating, at the imaging apparatus, a hyperfocal distance of the imaging apparatus;

iteratively calculating a range of focus distances based on the received range of distances and the estimated hyperfocal distance; and

acquiring a stack of images with the imaging apparatus by capturing at least one image at each calculated focus distance of the range of focus distances; and

creating the composite, extended depth-of-field image based on the stack of images acquired with the imaging apparatus.