Patent ID: 7965321

Claim:
An imaging device, comprising: an imaging unit that takes an image of a subject, to acquire image data; a compression unit that compresses in frame units the image data acquired by the imaging unit; a light quantity information calculation unit that calculates light quantity information including a shutter speed and a gain value, based on the image data acquired by the imaging unit; a compression ratio determination unit that determines a compression ratio for compression in frame units by the compression unit, based on the light quantity information calculated by the light quantity information calculation unit; a light quantity value calculation unit that calculates a light quantity value for determination of the compression ratio, based on the light quantity information; and a reference table for managing a threshold value and the compression ratio by association with each other, characterized in that: the compression unit compresses the image data in frame units based upon the compression ratio determined by the compression ratio determination unit, a threshold value suitable for the light quantity value calculated by the light quantity value calculation unit is selected, the reference table is referenced based on the selected threshold value, a compression ratio associated with the threshold value suitable for the light quantity value is acquired, a compression ratio for compression in frame units by the compression unit is determined, and the light quantity value calculation unit calculates the light quantity value A by: light quantity value A=shutter speed×gain value.