xiB & xiB-64 - Technical Manual Version 1.06
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4.2.
Video Formats
4.2.1.
Full Resolution
By default, each camera outputs a full resolution image based on its sensor specification.
4.2.2.
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.
Depending on the sensor inside xiB & xiB-64 cameras support the definition of one single ROI by specifying the size (width and
height) as well as the position (based on upper left corner) of the of the sub-area.
3.6 Model Specific Characteristics
4.2.3.
Downsampling Modes
Downsampling describes the possibility of reducing the image resolution without affecting the sensors physical size, ie. 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 skipping.
4.2.3.1.
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.
4.2.3.2.
Skipping
When skipping 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 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.