CHAPTER 2 FUNCTIONS & OPERATION
Analog signals proportionate to the
density of each picture element are output
as 4 parallel lines from the image sensor on
the CIS unit to the analog processor. The
analog processor carries out offset
adjustment, gain adjustment, and A/D
conversion. Analog signals are converted
into 16 bit digital signals in the analog
processor.
This image data is sent to the scanner
controller on the control PCB where shading
correction and one-dimensional gamma
correction are performed, and the data is
simultaneously converted into 8-bit data.
After this, data reordering, resolution
conversion, three-dimensional gamma
correction, and JPEG compression are
performed, and the data is output to the
computer via the USB interface.
Inside the computer, the various image
processing is executed according to the
user settings by the driver for this machine.
Whether to perform processing inside the
machine or on the computer varies
depending on the settings, even for the
same processing, in consideration of the
overall efficiency.
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CANON ELECTRONICS INC. 2011 CANON DR-M140 FIRST EDITION
