Method and apparatus for correcting tilt of subject ocuured in photographing, mobile terminal, and storage medium

• US 10,313,596 B2
• Filed: 05/21/2015
• Issued: 06/04/2019
• Est. Priority Date: 12/22/2014
• Status: Active Grant

• Current Assignee: ZTE Corporation
• Original Assignee: ZTE Corporation
• Inventors: Zhang, Yu, Zhou, Jie
• Primary Examiner(s): Vu, Kim Y
• Assistant Examiner(s): Bloom, Nathan J
• Application Number:
  US15/538,502
• Publication Number:
  US 20170352132A1
• Time in Patent Office: 1,475 Days
• Field of Search: None
• CPC Class Codes: G06T 2207/10024 Color image
• CPC Class Codes: G06T 3/60 Rotation of whole images or parts thereof
• CPC Class Codes: G06T 5/80 Geometric correction
• CPC Class Codes: G06T 7/194 involving foreground-background segmentation
• CPC Class Codes: H04N 2201/0084 Digital still camera
• CPC Class Codes: H04N 23/63 by using electronic viewfinders
• CPC Class Codes: H04N 23/632 for displaying or modifying preview images prior to image capturing, e.g. variety of image resolutions or capturing parameters
• CPC Class Codes: H04N 23/67 Focus control based on electronic image sensor signals
• CPC Class Codes: H04N 23/69 Control of means for changing angle of the field of view, e.g. optical zoom objectives or electronic zooming
• CPC Class Codes: H04N 23/80 Camera processing pipelines; Components thereof
• CPC Class Codes: H04N 5/2621 Cameras specially adapted for the electronic generation of special effects during image pickup, e.g. digital cameras, camcorders, video cameras having integrated special effects capability
• CPC Class Codes: H04N 5/2628 Alteration of picture size, shape, position or orientation, e.g. zooming, rotation, rolling, perspective, translation

Abstract

A method and an apparatus for correcting a tilt of a subject occurred in photographing, as well as a mobile terminal and a computer storage medium are provided. In some embodiments, the method includes: after it is detected by a mobile terminal that the subject enters a viewfinder interface, identifying a boundary of a profile of the subject to obtain the profile of the subject; analyzing the profile of the subject to determine whether the subject is tilted; and performing a process for straightening and photographing on the subject to obtain a picture in which the subject is straightened if the subject is determined to be tilted.

Claims

1. A method for correcting a tilt of a subject occurred in photographing, comprising:

in response to detecting, by a mobile terminal, the subject entering a viewfinder interface displayed on the mobile terminal, identifying a boundary of a profile of the subject to obtain the profile of the subject;

analyzing the profile of the subject to determine whether the subject is tilted; and

performing straightening and photographing on the subject to obtain a picture in which the subject is straightened in response to determining that the subject is tilted, wherein the performing comprises;

after performing a first operation on the subject in response to determining to perform straightening and photographing, obtaining a picture in which the subject is tilted according to a received photographing instruction; and

performing a second operation on the picture in which the subject is tilted to obtain the picture in which the subject is straightened;

wherein performing the first operation on the subject in response to determining to perform straightening and photographing comprises;

providing auxiliary lines, wherein the auxiliary lines are perpendicular to a longer side in the parallel sides of the profile of the subject, and the auxiliary lines pass through two corner points of the longer side in the parallel sides respectively; and

providing arrows, wherein the arrows are directed to the auxiliary lines from two corner points of a shorter side in the parallel sides of the profile of the subject respectively, and are indicative of movement directions of the two corner points of the shorter side in the parallel sides.

2. The method according to claim 1, wherein identifying the boundary of the profile of the subject to obtain the profile of the subject comprises:

comparing the subject with a background based on color and brightness, and identifying the boundary of the profile of the subject in accordance with differences between the subject and the background based on color and brightness and obtaining the profile of the subject.

3. The method according to claim 2, wherein analyzing the profile of the subject to determine whether the subject is tilted comprises:

determining whether the subject is photographed as a trapezoidal subject by determining whether the profile of the subject includes parallel sides and determining that a total number of the parallel sides is two; and

further determining whether to perform straightening and photographing in response to determining that the subject is photographed as the trapezoidal subject.

4. The method according to claim 3, wherein further determining whether to perform straightening and photographing in response to determining that the subject is photographed as the trapezoidal subject comprises:

determining whether the subject is at a center position of the viewfinder interface and whether an area of the subject exceeds a preset percentage of the viewfinder interface; and

determining to perform straightening and photographing on the trapezoidal subject in response to determining that the subject is at the center position of the viewfinder interface and the area of the subject exceeds the preset percentage of the viewfinder interface.

5. The method according to claim 1, wherein performing the second operation on the picture in which the subject is tilted to obtain the picture in which the subject is straightened comprises:

based on the profile of the subject, separating the subject from the background to obtain an image in which the subject is tilted; and

straightening the image in which the subject is tilted according to the arrows indicative of the movement directions of the two corner points of the shorter side in the parallel sides and obtaining the picture in which the subject is straightened.

9. A non-transitory computer storage medium storing a plurality of computer-executable instructions, wherein the plurality of computer-executable instructions are used for executing the method according to claim 1.

10. The non-transitory computer storage medium according to claim 9, wherein identifying the boundary of the profile of the subject to obtain the profile of the subject comprises:

comparing the subject with a background based on color and brightness, and identifying the boundary of the profile of the subject in accordance with differences between the subject and the background based on color and brightness and obtaining the profile of the subject.

11. The non-transitory computer storage medium according to claim 10, wherein analyzing the profile of the subject to determine whether the subject is tilted comprises:

determining whether the subject is photographed as a trapezoidal subject by determining whether the profile of the subject includes parallel sides and determining that a total number of the parallel sides as two; and

further determining whether to perform straightening and photographing in response to determining that the subject is photographed as the trapezoidal subject.

12. The non-transitory computer storage medium according to claim 11, wherein further determining whether to perform straightening and photographing in response to determining that the subject is photographed as the trapezoidal subject comprises:

determining whether the subject is at a center position of the viewfinder interface and whether an area of the subject exceeds a preset percentage of the viewfinder interface; and

determining to perform straightening and photographing on the trapezoidal subject in response to determining that the subject is at the center position of the viewfinder interface and the area of the subject exceeds the preset percentage of the viewfinder interface.

13. The non-transitory computer storage medium according to claim 9, wherein performing the second operation on the picture in which the subject is tilted to obtain the picture in which the subject is straightened comprises:

based on the profile of the subject, separating the subject from the background to obtain an image in which the subject is tilted; and

straightening the image in which the subject is tilted according to the arrows indicative of the movement directions of the two corner points of the shorter side in the parallel sides and obtaining the picture in which the subject is straightened.

6. An apparatus for correcting a tilt of a subject occurred in photographing, comprising a processor configured to:

identify, in response to detecting, by a mobile terminal, the subject entering a viewfinder interface displayed on the mobile terminal, a boundary of a profile of the subject to obtain the profile of the subject;

analyze the profile of the subject to determine whether the subject is tilted; and

perform straightening and photographing on the subject to obtain a picture in which the subject is straightened in response to determining that the subject is tilted;

obtain, after performing a first operation on the subject in response to determining to perform straightening and photographing, a picture in which the subject is tilted according to a received photographing instruction; and

perform a second operation on the picture in which the subject is tilted and obtain the picture in which the subject is straightened;

wherein the processor is configured to perform the first operation on the subject in response to determining to perform straightening and photographing by;

providing auxiliary lines, wherein the auxiliary lines are perpendicular to a longer side in the parallel sides of the profile of the subject, and the auxiliary lines pass through two corner points of the longer side in the parallel sides respectively; and

providing arrows, wherein the arrows are directed to the auxiliary lines from two corner points of a shorter side in the parallel sides of the profile of the subject respectively, and are indicative of movement directions of the two corner points of the shorter side in the parallel sides.

7. The apparatus according to claim 6, wherein the processor is further configured to:

determine whether the subject is photographed as a trapezoidal subject by determining whether the profile of the subject includes parallel sides and determining that a total number of the parallel sides is two; and

further determine whether to perform straightening and photographing in response to determining that the subject is photographed as the trapezoidal subject.

8. A mobile terminal, comprising a camera and a processor,

wherein the processor is configured to:

identify, in response to detecting, by the processor, a subject entering a viewfinder interface of the camera, a boundary of a profile of the subject to obtain the profile of the subject;

to analyze the profile of the subject to determine whether the subject is tilted;

perform straightening and photographing on the subject to obtain a picture in which the subject is straightened in response to determining that the subject is tilted;

obtain, after performing a first operation on the subject in response to determining to perform straightening and photographing, a picture in which the subject is tilted according to a received photographing instruction; and

perform a second operation on the picture in which the subject is tilted and obtain the picture in which the subject is straightened;

wherein the processor is further configured to perform the first operation on the subject in response to determining to perform straightening and photographing by;

providing auxiliary lines, wherein the auxiliary lines are perpendicular to a longer side in the parallel sides of the profile of the subject, and the auxiliary lines pass through two corner points of the longer side in the parallel sides respectively; and

providing arrows, wherein the arrows are directed to the auxiliary lines from two corner points of a shorter side in the parallel sides of the profile of the subject respectively, and are indicative of movement directions of the two corner points of the shorter side in the parallel sides.