Piper

struct StaticOutputDescriptor {

    # Properties of an output, that is, a single stream of features

    # produced in response to process and finish requests. A feature

    # extractor may have any number of outputs, and it always

    # calculates and returns features from all of them when

    # processing; this is useful in cases where more than one feature

    # can be easily calculated using a single method.

    # 

    # This structure contains the properties of an output that are

    # static, i.e. that do not depend on the parameter values provided

    # at configuration, excluding the Basic struct parameters like id

    # and description.  The Basic struct properties are not included

    # for historical reasons: they were already referenced separately

    # in the OutputDescriptor and ExtractorStaticData before this

    # struct was introduced.

    typeURI            @0  :Text;                 # URI indicating the sort of feature that this output returns (see docs).

}

    # All the properties of an output, both static (the basic metadata and static

    # descriptor) and potentially dependent on configuration parameters (the

    # configured descriptor).

    static             @2  :StaticOutputDescriptor;        # Properties (other than Basic) that do not depend on parameters.

    struct SOPair {

        # A mapping between output identifier and static descriptor for

	# that output.

        output         @0  :Text;                 # Output id, matching the output's descriptor's basic identifier.

        static         @1  :StaticOutputDescriptor;

    }

    staticOutputInfo   @12 :List(SOPair);         # Static descriptors for all outputs that have any static metadata.