QgsProcessingParameterField|column|Name of column to use for buffer distances|None|input|-1|False|True
QgsProcessingParameterNumber|scale|Scaling factor for attribute column values|QgsProcessingParameterNumber.Double|1.0|True|None|None
QgsProcessingParameterNumber|tolerance|Maximum distance between theoretical arc and polygon segments as multiple of buffer|QgsProcessingParameterNumber.Double|0.01|True|None|None