Focusing method

• US 9,832,359 B2
• Filed: 01/08/2014
• Issued: 11/28/2017
• Est. Priority Date: 10/16/2013
• Status: Expired due to Fees

• Current Assignee: Novatek Microelectronics Corporation (Novatek Microelectronics Corp Limited)
• Original Assignee: Novatek Microelectronics Corporation (Novatek Microelectronics Corp Limited)
• Inventors: Hsu, Wei
• Primary Examiner(s): Hogue, Dennis
• Assistant Examiner(s): Morehead, III, John H
• Application Number:
  US14/149,840
• Publication Number:
  US 20150103231A1
• Time in Patent Office: 1,420 Days
• CPC Class Codes: H04N 23/61 based on recognised objects
• 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 23/959 by adjusting depth of field during image capture, e.g. maximising or setting range based on scene characteristics

Abstract

A focusing method for an image capturing device includes determining a first focus distance according to a first focus frame of the plurality of focus frames; capturing a first image according to the first focus frame, determining a second focus distance according to a second focus frame of the plurality of focus frames, and detecting whether a second depth of field corresponding to the second focus distance is overlapping with a first depth of field corresponding to the first focus distance, for determining whether to capture a second image according to the second focus distance.

Claims

1. A focusing method for an image capturing device, comprising:

detecting a plurality of focus frames of a plurality of characteristic points in a capturing area;

determining a first focus distance according to a first focus frame of the plurality of focus frames;

capturing a first image according to the first focus distance;

determining a second focus distance according to a second focus frame of the plurality of focus frames;

detecting whether a second depth of field corresponding to the second focus distance is overlapping with a first depth of field corresponding to the first focus distance, for determining whether to capture a second image according to the second focus distance; and

capturing the second image according to the second focus distance after determining that the second depth of field corresponding to the second focus distance is not overlapping with the first depth of field corresponding to the first focus distance.

2. The focusing method of claim 1, wherein the plurality of characteristic points is a plurality of face positions in the capturing area.

3. The focusing method of claim 1, wherein the step of detecting whether the second depth of field corresponding to the second focus distance is overlapping with the first depth of field corresponding to the first focus distance, for determining whether to capture the second image according to the second focus distance comprises:

determining not to capture the second image when the second depth of field corresponding to the second focus distance is overlapping with the first depth of field corresponding to the first focus distance.

4. A focusing method for an image capturing device, comprising:

detecting a plurality of focus frames of a plurality of characteristic points in a capturing area;

determining a plurality of focus distances and a plurality of depths of field of the plurality of focus distances according to the plurality of focus frames;

generating at least one overlapped group by classifying the plurality of focus distances according to the plurality of depths of field, each overlapped group comprising a number of the plurality of focus distances, wherein a depth of field corresponding to each focus distance in the overlapped group overlaps with depths of field of other focus distances in the overlapped group; and

capturing a plurality of images according to focus distances included in each overlapped group after generating the at least one overlapped group.

5. The focusing method of claim 4, wherein the plurality of characteristic points is a plurality of face positions in the capturing area.

6. The focusing method of claim 4, wherein the step of capturing the plurality of images-according to the focus distances included in each overlapped group after generating the at least one overlapped group comprises:

calculating a focus distance average according to the focus distances included in each overlapping group; and

capturing the plurality of images according to the focus distance average of each overlapping group.