8.Features
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On color cameras, if you specify a horizontal Decimation factor of n, the camera transmits only every n
th
pair of columns. For example, if you specify a horizontal Decimation factor of 2, the camera skips columns
1 and 2, transmits columns 3 and 4, skips columns 5 and 6, and so on.
Figure 8-38 Mono camera horizontal Decimation
Figure 8-39 Color camera horizontal Decimation
As a result, the image width is reduced. For example, enabling horizontal Decimation by 2 halves the
image width. The camera automatically adjusts the image ROI settings.
Horizontal Decimation does not (or only to a very small extent) increase the camera's frame rate.
Configuring Decimation
To configure vertical Decimation, enter a value for the DecimationVertical parameter. To configure
horizontal Decimation, enter a value for the DecimationHorizontal parameter.
The value of the parameters defines the Decimation factor. Depending on your camera model, the following
values are available:
1: Disable Decimation.
2: Enable Decimation.
Considerations When Using Decimation
1) Effect on ROI settings
When you are using Decimation, the settings for your image ROI refer to the resulting number of rows and
columns. Taking MER-502-79U3M/C(-L) as an example, the camera's default resolution is 2448×2048.
When horizontal Decimation by 4 and vertical Decimation by 4 are enabled, the maximum ROI width would
be 612, and the maximum ROI height would be 512.
2) Reduced resolution
Using Decimation effectively reduces the resolution of the camera's imaging sensor. Taking MER-502-
79U3M/C(-L) as an example, the camera's default resolution is 2448×2048. When horizontal Decimation
by 4 and vertical Decimation by 4 are enabled, the effective resolution of the sensor is reduced to 612×512.
3) Possible image distortion
