Patent ID: 8462229

Claim:
A method comprising: setting a readout frequency of a sensor of a digital image capturing device based on a frequency of alternating current (AC) mains so that a readout period of the sensor of the digital image capturing device is not an integer multiple of a flicker period, the flicker period equal to half of a period of the AC mains; capturing a first image frame and a second image frame using the sensor of the digital image capturing device, the second image frame captured later in time than the first image frame; and, detecting whether flicker has occurred in the first image frame and the second image frame due to a periodic fluctuation of light emitted by a light source powered by the AC mains, by: determining a first brightness of an area of the first image frame, the area having a size less than a size of the first image frame; determining a second brightness of an area of the second image frame corresponding to the area of the first image frame; in response to determining that the first brightness is equal to the second brightness, determining that the first brightness and the second brightness are naturally occurring and that no flicker from the light source has occurred; in response to determining that the first brightness is unequal to the second brightness, determining that the first brightness and the second brightness are not naturally occurring and that flicker from the light source has occurred.