A digital image acquisition system includes a portable apparatus for
capturing digital images and a digital processing component for
detecting, analyzing, invoking subsequent image captures and informing
the photographer regarding motion blur, and for reducing camera motion
blur in an image captured by the apparatus. The digital processing
component operates by comparing the image with at least one other image,
for example a preview image, of nominally the same scene taken outside
the exposure period of the main image. In one embodiment the digital
processing component identifies at least one feature in a single preview
image which is relatively less blurred than the corresponding feature in
the main image, calculates a point spread function (PSF) in respect of
such feature, and initiates a subsequent capture if determined that the
motion blur exceeds a certain threshold. In another embodiment the
digital processing determines the degree of blur by analyzing the motion
blur in the captured image itself, and initiates a subsequent capture if
determined that the motion blur exceeds a certain threshold. Such real
time analysis may use the auto focusing mechanism to qualitatively
determine the PSF.