IDS peak 2.8.0 / uEye+ firmware 3.33
Binning is a technique to reduce image resolution by typically summarizing or averaging a certain amount of pixels in rows, columns, or both columns and rows. The field of view (FOV) is retained. For example, a 1x2 binning would halve the resolution by combining 2 neighboring pixels in a row. Other factor combinations are possible, such as 2x2, 2x1, 1x4, ...
•If the pixel values are added, the image brightness increases.
•If the pixel values are averaged, the image noise is reduced.
Binning distinguishes whether a camera performs monochrome or color binning:
Monochrome binning
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Additive binning |
Averaging binning |
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Mono |
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Fig. 21: Binning with factor 2 on monochrome sensors
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Some color sensors combine neighboring Bayer pattern pixels; in this case, the color information gets lost (mono binning). |
Color binning
With color cameras, binning is possible too and is usually applied when the image still is in RAW Bayer format. In this case, binning works on each color separately, such that red pixels are combined with red pixels (R), blue with blue (B) and green with green in the red-green row (Gr) and in the green-blue row (Gb) separately. This way, color is preserved.
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Additive binning |
Averaging binning |
Weighted binning |
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Color |
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Fig. 22: Binning with factor 2 on color sensors
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For some monochrome sensors, the camera also performs color binning. If you imagine that a Bayer pattern is placed in front of the monochrome sensor, then only the pixels that have the same color in the Bayer pattern would be added together. This means that the odd pixels of each row or column are combined and the even pixels of each row or column are combined. Color binning on monochrome sensors results in slight artifacts. |
Binning options on the camera
•Sensor binning:
Some sensors support binning on the sensor, some in both directions, some just in vertical direction. Binning reduces the amount of data. After binning, the image is processed in the camera and transferred to the host PC. This usually increases the maximum frame rate.
•FPGA binning:
Most uEye+ cameras support binning, even if the sensor does not support it. The FPGA in the camera combines the pixels and the reduced resolution is transferred to the host PC. The maximum frame rate can only be increased, if the limiting factor is the bandwidth.
Refer to the "List of supported features" for GigE Vision cameras and USB3 Vision cameras for more information on a specific camera model.
Depending on the model, the cameras support different binning factors that can be configured in horizontal and vertical direction independently. Exception is sensor binning for some sensors, where binning factors can only be applied in combination, e.g. as 2x2 binning. Binning can be used e.g. as fast preview for high-resolution cameras. Binning also improves the signal-to-noise ratio (SNR). With respect to SNR, sensor binning can outperform FPGA binning, if read out noise is improved, too. Additive binning increases image brightness, which is beneficial for visualization.
Debayering and binning/decimation
Debayering (see Color sensors) may cause image artifacts such as edge effects ("aliasing") or false colors at object edges. The use of binning or decimation can increase the occurrence of Bayer artifacts, such as false colors. These false colors can be more or less intense depending on the debayering method used.
 Fig. 23: Image data without debayering (RAW) |
 Fig. 24: Image data with debayering and without binning |
 Fig. 25: Image data with debayering and 2x2 binning |
