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8.1.4 Fixed Pattern Noise Correction (FPNC)
CMOS sensors exhibit nonuniformities that are often called fixed pattern noise (FPN).
However it is no noise but a fixed variation from pixel to pixel that can be corrected. The
advantage of using this correction is a more homogeneous picture which may simplify the
image analysis. Variations from pixel to pixel of the dark signal are called dark signal non-
uniformity (DSNU) whereas photo response nonuniformity (PRNU) describes variations
of the sensitivity. DNSU is corrected via an offset while PRNU is corrected by a factor.
The correction is based on columns. It is important that the correction values are comput-
ed for the used sensor readout configuration. During camera production this is derived for
the factory defaults. If other settings are used (e.g. different number of readout channels)
using this correction with the default data set may degrade the image quality. In this case
the user may derive a specific data set for the used setup.
FPN Correction Off
FPN Correction On
8.1.4.1 VEXG
Camera Type
FPNC
Monochrome
VEXG-02M
■
VEXG-13M
■
VEXG-25M
■
VEXG-52M.R
■
VEXG-100M.R
■
Color
VEXG-02C
■
VEXG-13C
■
VEXG-25C
■
VEXG-52C.R
■
VEXG-100C.R
■
8.1.4.2 VEXU
Notice
On cameras with Sony sensors additional FPN correction is not necessary.
Camera Type
FPNC
Monochrome
VEXU-24M
□
Color
VEXU-24C
□
Содержание VEXG
Страница 2: ...2 ...
Страница 39: ...39 8 1 2 3 Pixel Formats VEXU Camera Type Mono8 Mono12 Bayer RG8 Bayer RG12 Monochrome VEXU 24M Color VEXU 24C ...
Страница 67: ...67 ...