MT9V135L12STCES Micron Technology Inc, MT9V135L12STCES Datasheet - Page 13

• Manufacturer Part Number: MT9V135L12STCES
• Manufacturer: Micron Technology Inc

Specifications of MT9V135L12STCES

• Lead Free Status / RoHS Status: Compliant

Defect Correction
Color Correction
Color Saturation Control
Automatic White Balance
Auto Exposure
PDF: 09005aef82c99cd/Source:09005aef824c99db
MT9V135_LDS_2.fm - Rev. B 3/07 EN
This device supports 2D defect correction. In 2D defect detection/correction, pixels with
values different from their neighbors by greater than a defined threshold are considered
defects unless near the image boundary. The approach is termed 2D, as pixels on neigh-
boring lines as well as neighboring pixels on the same line are considered in both detec-
tion and correction.
To obtain good color rendition and saturation, it is necessary to compensate for the
differences between the spectral characteristics of the imager color filter array and the
spectral response of the human eye. This compensation, also known as color separation,
is achieved through linear transformation of the image with a 3 x 3 element color correc-
tion matrix. The optimal values for the color correction coefficients depend on the
spectra of the incident illumination and can be programmed by the user.
Both color saturation and sharpness enhancement can be set by the user, or adjusted
automatically by tracking the magnitude of the gains used by the auto exposure algo-
rithm.
The MT9V135 has a built-in AWB algorithm designed to compensate for the effects of
changing scene illumination on the quality of the color rendition. This sophisticated
algorithm consists of two major submodules:
• A measurement engine (ME) performing statistical analysis of the image.
• A module selecting the optimal color correction matrix and analog color channel
While the default algorithm settings are adequate in most situations, the user can repro-
gram base color correction matrices and limit color channel gains. The AWB does not
attempt to locate the brightest or grayest elements in the image; it performs in-depth
image analysis to differentiate between changes in predominant spectra of illumination
and changes in predominant scene colors. Factory defaults are suitable for most appli-
cations; however, a wide range of algorithm parameters can be overwritten by the user
through the serial interface.
The auto exposure algorithm performs automatic adjustments to image brightness by
controlling exposure time and analog gains in the sensor core, as well as digital gain
applied to the image. The algorithm relies on the auto exposure measurement engine
that tracks speed and amplitude changes in the overall luminance of selected windows
in the image.
Back light compensation is achieved by weighting the luminance in the center of the
image higher than the luminance on the periphery. Other algorithm features include
fast-fluctuating illumination rejection (time averaging), response-speed control, and
controlled sensitivity to small changes.
While the default settings are adequate in most situations, the user can program target
brightness, measurement window, and other parameters as described above. The auto
exposure algorithm enables compensation for a broad range of illumination intensities.
gains in the sensor core.
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MT9V135: SOC VGA Digital Image Sensor
Micron Technology, Inc., reserves the right to change products or specifications without notice.
Detailed Architecture Overview
©2006 Micron Technology, Inc. All rights reserved.
Preliminary