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3 General features
3.1 Camera features
3.1.1 ROIs – Region of interest
ROI , also called area-of-interest (AOI) or windowing, allows the user to specify a sub-area of the original sensor size for read-out. ROI can
be set by specifying the size (width and height) as well as the position (based on upper left corner) of the of the sub-area.
3.1.2 Downsampling modes
Downsampling describes the possibility of reducing the image resolution without affecting the sensors physical size, i.e. without reducing
the physical size of the sensing area. This feature is useful when optics are used, that are particularly fitted to a certain sensor size and if
it is necessary to maintain the full image circle on the sensor.
Downsampling can be achieved in two ways: binning and decimation.
Binning/decimation selector selects which binning/decimation engine is used (Sensor,
FPGA , CPU). After setting of selector, multiple pa-
rameters could be get or set for the selected unit.
They can be divided into:
Patterns define the horizontal/vertical pattern how photo-sensitive cells are combined (mono or bayer)
Values reduce the horizontal or vertical resolution of the image by the specified horizontal/vertical downsampling factor
Modes in case of binning set the mode used to combine horizontal/vertical photo-sensitive cells together (sum or average)
Binning
When binning is applied, the image is divided into cluster of k*l pixels, where all pixels in each cluster are interpolated and result in the
value of one output pixel. For example, a 2*2 binning produces 2*2-pixel clusters and results in images with ¼ of the original resolution.
Decimation – Skipping
When decimation is chosen, only every n-th pixel is used to create the output image. For example, with a 2x1 vertical skipping, every odd
number line is used and every even number line is skipped, resulting in an image with half its original vertical resolution. Skipping is a
faster downsampling mode, but also introduces more aliasing effects.
XIMEA Technical Manual, Version: v240108 63