1. A set of application program interfaces embodied on a computer readable medium for execution on a processor in conjunction with an application program for determining a direct hydrocarbon indicator from seismic data comprising: a first interface for receiving a hydrocarbon associated exemplar data group and a non-hydrocarbon associated exemplar data group from seismic data associated with a plurality of data sensor locations to obtain hydrocarbon exemplar group members and non-hydrocarbon exemplar group members, a second interface for calculating hydrocarbon exemplar data group probability density function values and non-hydrocarbon exemplar data group probability density function values over an attribute space based on selected distribution values of seismic data attributes of the hydrocarbon exemplar group members and non-hydrocarbon exemplar group members and a third interface for applying a Bayesian inversion to determine exemplar data group membership probability for seismic data associated with at least one of the plurality of seismic data sensor locations by distribution values of the seismic attribute values of the seismic data associated with at least one of the plurality of seismic data sensor locations to at least one of the calculated hydrocarbon exemplar data group probability density function values and non-hydrocarbon exemplar data group probability density function values.