Patent ID: 7667765
Filing Date: 2010-02-23
Classification: H04N

Abstract:
1. A method for calibrating a shutter of a digital imaging device, comprising: capturing, throughout a total exposure period, first and second exposures from a field of an imaging sensor of the digital imaging device, the shutter remaining open for the total exposure period, the first exposure starting when the shutter opens and being terminated under electronic control before the total exposure period has elapsed, the first exposure having a known duration, the second exposure starting immediately following terminating of the first exposure and being terminated upon closing of the shutter; and comparing a characteristic of the first and second exposures, respectively, to obtain the actual duration of the total exposure period; wherein comparing the characteristic of the first and second exposures, respectively, to obtain the actual duration of the total exposure period comprises computing a ratio of accumulated pixel values from the first exposure to accumulated pixel values of the second exposure or computing a ratio of accumulated pixel values from the second exposure to accumulated pixel values of the first exposure.