IMAGING APPARATUS, FLASH DETERMINATION METHOD, AND RECORDING MEDIUM

• US 20110001849A1
• Filed: 07/01/2010
• Published: 01/06/2011
• Est. Priority Date: 07/03/2009
• Status: Active Grant

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: FURUKAWA, Yutaka, WADA, Noriaki
• Granted Patent: US 8,502,893 B2
• Time in Patent Office: Days
• US Class Current: 348/241
• CPC Class Codes: H04N 23/73 by influencing the exposure time
• CPC Class Codes: H04N 23/74 by influencing the scene brightness using illuminating means
• CPC Class Codes: H04N 25/531 by controlling rolling shutters in CMOS SSIS

Abstract

An imaging apparatus capable of increasing the accuracy of detection of an outside flash of light.

The imaging apparatus includes an imaging unit that sequentially captures images using a CMOS-type image sensor, and a flash determination unit that determines the presence/absence of a flash based on the images captured by the imaging unit. The flash determination unit monitors an amount of change in the average luminance level of a predetermined region in the lower area of the screen in the images captured by the imaging unit, and determines the presence/absence of a flash based on the amount of change in the average luminance level.

Claims

1. An imaging apparatus comprising:

an imaging unit that includes a CMOS-type image sensor and obtains an image by converting light from a subject into an electrical signal; and

a determination unit that sets a predetermined region in the lower portion of the image obtained by the imaging unit as a flash detection monitoring region, calculates an evaluation value from the flash detection monitoring region, and determines that the influence of a flash is present within the image when the calculated evaluation value has changed by greater than or equal to a predetermined value.

2. The imaging apparatus according to claim 1,

wherein the determination unit sets a region configured of a predetermined number of lines that includes the lowermost line of the image as the flash detection monitoring region.

3. The imaging apparatus according to claim 1,

wherein the determination unit divides the flash detection monitoring region into n regions (where n is an integer greater than or equal to 2), calculates a dividing region evaluation value for each of the n regions obtained through the dividing, monitors an amount of change in all or some of the calculated n dividing region evaluation values, and determines the presence/absence of the influence of a flash within the image based on the amount of change in the dividing region evaluation values in all of the dividing regions among the dividing regions that are being monitored.

4. The imaging apparatus according to claim 1, further comprising:

a correction unit that performs a process for correcting the influence of a flash in the image obtained by the imaging unit in the case where the determination unit has determined that the influence of a flash is present within the image.

5. A flash determination method comprising:

(a) obtaining an image by converting light from a subject into an electrical signal using a CMOS-type image sensor; and

(b) setting a predetermined region in the lower portion of the image obtained in the step (a) as a flash detection monitoring region, calculating an evaluation value from the flash detection monitoring region, and determining that the influence of a flash is present within the image when the calculated evaluation value has changed by greater than or equal to a predetermined value.

6. The flash determination method according to claim 5,

wherein in the step (b), a region configured of a predetermined number of lines that includes the lowermost line of the image is set as the flash detection monitoring region.

7. The flash determination method according to claim 5,

wherein in the step (b), the flash detection monitoring region is divided into n regions (where n is an integer greater than or equal to 2), a dividing region evaluation value is calculated for each of the n regions obtained through the dividing, an amount of change in all or some of the calculated n dividing region evaluation values is monitored, and the presence/absence of the influence of a flash within the image is determined based on the amount of change in the dividing region evaluation values in all of the dividing regions among the dividing regions that are being monitored.

8. The flash determination method according to claim 5, further comprising:

(c) performing a process for correcting the influence of a flash in the image obtained by the imaging unit in the case where it has been determined in the step (b) that the influence of a flash is present within the image.

9. A recording medium in which is recorded a program for causing a computer to execute a flash determination method, the method comprising:

(a) obtaining an image by converting light from a subject into an electrical signal using a CMOS-type image sensor; and

(b) setting a predetermined region in the lower portion of the image obtained in the step (a) as a flash detection monitoring region, calculating an evaluation value from the flash detection monitoring region, and determining that the influence of a flash is present within the image when the calculated evaluation value has changed by greater than or equal to a predetermined value.