2d splines to tangential arcs

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I need to convert 2d splines to arcs, before I send the file out to a laser cutter.
Tangential arcs would be great.
Is there a stand-alone software package that I am able to open a DXF file with splines and then simply convert the splines to a series of tangential arcs.
I would like to be able to control the length of the smallest entity and or the accuracy.
thanks

Rhino. You can specifythe fit tolerance.