Digital photographing device

• US 20030223007A1
• Filed: 06/03/2003
• Published: 12/04/2003
• Est. Priority Date: 06/03/2002
• Status: Active Grant

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Inventors: Takane, Yasuo
• Granted Patent: US 7,265,787 B2
• Time in Patent Office: Days
• US Class Current: 348/335
• CPC Class Codes: H04N 23/633 for displaying additional information relating to control or operation of the camera
• CPC Class Codes: H04N 23/673 based on contrast or high frequency components of image signals, e.g. hill climbing method
• CPC Class Codes: H04N 25/61 the noise originating only from the lens unit, e.g. flare, shading, vignetting or "cos4"

Abstract

A digital photographing device in which processing time for correcting optical distortion is shortened. A first distortion correction circuit, which can carry out processing at a low correction accuracy but in a short time, and a second distortion correction circuit, which carries out processing at a high correction accuracy but requires time for processing, are provided at an image processing circuit for processing digital image data. Control is carried out such that the second distortion correction circuit is selected and carries out optical distortion correction at a high accuracy only at a time of actually photographing a still image (i.e., when the still image photographing mode is selected and a release button is depressed fully). In other cases, control is carried out such that the first distortion correction circuit is selected.

Claims

1. A digital photographing device photographing a subject via an optical lens and acquiring digital image data expressing the subject, the digital photographing device comprising:

a plurality of correction sections correcting optical distortion included in the digital image data, and having different correction accuracies and different processing speeds corresponding to the correction accuracies;

a photographing mode selecting section for selecting at least which of a still image photographing mode and a dynamic image photographing mode the subject is to be photographed in; and

a control section which, on the basis of results of selection by the photographing mode selecting section, selects the correction section, and carries out control such that the optical distortion of the digital image data is corrected by the selected correction section.

2. The digital photographing device of claim 1, wherein, during a series of photographing processings from selection of the photographing mode by the photographing mode selecting section to completion of photographing in accordance with that photographing mode, the control section switches selection of the correction section at each predetermined processing stage.

3. The digital photographing device of claim 1, further comprising a correction execution selecting section for setting whether or not the correction is to be executed,

wherein the control section discontinues correction by the correction section when it is selected by the correction execution selecting section that correction is not to be executed.

4. The digital photographing device of claim 2, further comprising a correction execution selecting section for setting whether or not the correction is to be executed,

wherein the control section discontinues correction by the correction section when it is selected by the correction execution selecting section that correction is not to be executed.

5. The digital photographing device of claim 3, wherein, when correction is discontinued, correction information relating to the discontinued correction is stored in a storing section.

6. The digital photographing device of claim 5, wherein the correction information includes at least one of information expressing that correction has not been carried out, and a polynomial approximating the optical distortion which polynomial is needed at a time of carrying out correction later.

7. The digital photographing device of claim 6, wherein the correction information is stored in the storing section together with digital image data for which correction was discontinued.

8. The digital photographing device of claim 4, wherein, when correction is discontinued, correction information relating to the discontinued correction is stored in a storing section.

9. The digital photographing device of claim 8, wherein the correction information includes at least one of information expressing that correction has not been carried out, and a polynomial approximating the optical distortion which polynomial is needed at a time of carrying out correction later.

10. The digital photographing device of claim 9, wherein the correction information is stored in the storing section together with digital image data for which correction was discontinued.

11. The digital photographing device of claim 1, wherein the correction section having a relatively low correction accuracy corrects optical distortion with respect to only a predetermined one direction.

12. The digital photographing device of claim 1, wherein, at at least one of the correction sections, an image size of an object of correction is fixed.

13. The digital photographing device of claim 1, wherein, for each of the plurality of correction sections, an output destination of digital image data after correction is fixed.

14. The digital photographing device of claim 1, wherein the correction sections approximate the optical distortion by a polynomial, and correct the optical distortion by interpolating each pixel after correction from digital image data before correction.

15. The digital photographing device of claim 2, wherein the correction section having a relatively low correction accuracy corrects optical distortion with respect to only a predetermined one direction.

16. The digital photographing device of claim 2, wherein, at at least one of the correction sections, an image size of an object of correction is fixed.

17. The digital photographing device of claim 2, wherein, for each of the plurality of correction sections, an output destination of digital image data after correction is fixed.

18. The digital photographing device of claim 2, wherein the correction sections approximate the optical distortion by a polynomial, and correct the optical distortion by interpolating each pixel after correction from digital image data before correction.