Festo SBSC-EN, Manual

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Page 142 Vision Sensor SBSI/SBSC-EN, 8062650 - 1607b - 13/09/2016
Vision Sensor Manual
4.6.3.10.4 Barcode detector, tab Lines
Fig. 138: Detector Barcode, tab Lines
Settings in tab Lines
Parameters Functions
Minimum Size
Minimal size of bar code elements, i.e. the minimal width of bars and spaces. For
small bar codes the value should be reduced to 1.5. In the case of huge bar codes the
value should be increased, which results in a shorter execution time.
Maximum Size
Maximal size of bar code elements, i.e. the maximal width of bars and spaces. This
value should be adequate low such that two neighbouring bar codes are not fused
into a single one. On this other hand the value should be sufficiently high in order to
find the complete bar code region.
Minimum height
Minimal bar code height. In the case of a bar code with a height of less than 16 pixels
the respective height should be set by the user. Note, that the minimal value is 8
pixels. If the bar code is very high, i.e. 70 pixels and more, manually adjusting to the
respective height can lead to a speed-up of the subsequent finding and reading
operation.
Orientation
Expected bar code orientation. If the bar codes are expected to appear only in
certain orientations in the processed images, one can reduce the orientation range
adequately. This enables an early identification of false candidates and hence shorter
execution times. This adjustment can be used for images with a lot of texture, which
includes fragments tending to result in false bar code candidates.
Orientation
tolerance
Orientation tolerance. See the explanation of ’orientation’ parameter.
Measuring
threshold
The bar-space-sequence of a bar code is determined with a scan line measuring the
position of the edges. In the case of disturbances in the bar code region or a high
noise level, this value should be increased.
Max. diff
orientation
A potential bar code region contains bars, and hence edges, with a similar
orientation. This value denotes the maximal difference in this orientation between
adjacent pixels and is given in degree. If a bar code is of bad quality with jagged edges
this parameter should be set to bigger values. If the bar code is of good it can be set
to smaller values, thus reducing the number of potential but false bar code
candidates.