A system and method for automatically determining a set of default settings
(with respect to a blank image) so that a uniform and high contrast image
results when, for example, a finger is present on a sensor device. A
background noise image and other diagnostic data, such as non-functional
areas, are also automatically determined with respect to the blank image
and stored for future reference. The above processing is performed each
time the sensor device is initialized. Once the initialization process is
complete, the individual places the required biometric feature, for
example, a finger on the sensor device. The methodology adjusts the set of
default settings to account for the condition of the biometric feature
being imaged by increasing or decreasing the sensitivity level of the
sensor device. The determination of optimum sets is achieved by analyzing
specific regions of the image data rather than the entire image. The
present invention then captures multiple images at different sensitivity
levels since a specific region may be optimized with respect to one set of
settings and another region may be optimized with respect to another set
of settings. The diagnostic data is then used to correct the captured
images by substituting any non-functional areas in the sensor device with
average intensity values from neighboring regions. The multiple images are
then combined to form a resultant image by using a weighted and
intensity-transformed combination of regions from the different images.