Please cite SAGA whenever you use it for your publications:

Vectorising grid classes.

Name	Type	Identifier	Constraints
Input
Grid	grid, input	GRID
Output
Polygons	shapes, output	POLYGONS
Options
Class Selection	choice	CLASS_ALL	Available Choices: [0] one single class specified by class identifier [1] all classes Default: 1
Class Identifier	floating point number	CLASS_ID	Default: 1
Split Distinct Polygon Parts	choice	SPLIT	Available Choices: [0] no [1] yes Default: 0
Vertices	choice	VERTICES	Available Choices: [0] cell corners [1] smoothed cell corners [2] cell edge centers [3] cell edge center with less smoothed cell corners [4] cell edge center with smoothed cell corners Default: 0