Lattice encoding

A method of generating data defining a speech lattice comprising:

• receiving data defining a first speech lattice comprising a plurality of nodes interconnected by links, said links being associated with data identifying speech units;
• processing said received data to determine a second speech lattice comprising a planar graph having a number of nodes interconnected by links where none of the links cross, said links being associated with data identifying speech units, the nodes and links of said planar graph defining vertices and edges of areas in a two dimensional plane;
• generating as data defining said planar graph, identifying data identifying the number of links bounding each said area defined by said planar graph and the location of said areas within said planar graph;
• and
• outputting as data defining said second speech lattice said identifying data and data identifying speech units associated with links of the planar graph defined by said identifying data.

A method of generating a lattice comprising:

• receiving shape data defining a number of areas in a two dimensional plane having vertices and edges corresponding the nodes and links in a planar graph where none of said links cross;
• receiving items of hypothesis data associating links of the planar graph defined by shape data with data identifying units;
• and
• generating a lattice comprising a plurality of nodes connected via links by:
• determining the planar graph defined by said shape data;
• and
• associating the links of said determined planar graph with units utilising said hypothesis data.

A method of generating data defining a lattice structure comprising:

• receiving data defining a lattice structure comprising a plurality of nodes interconnected by links;
• processing the received data to determine the differences between an embedding of said lattice structure in a two dimensional plane and a planar graph comprising a number of nodes interconnected by links where none of the links cross, the nodes and links of said planar graph defining edges and vertices of areas in a two dimensional plane;
• generating difference data identifying said determined differences;
• generating for said areas of said two dimensional plane defined by said planar graph, identifying data identifying the number of links bounding each said area and data identifying of the location of the said area within said planar graph;
• and
• outputting as data defining said lattice structure, said generated identifying data and said generated difference data.

Apparatus for generating recognition data, comprising:

• a receiver operable to receive lattice data defining a lattice structure comprising a plurality of nodes connected by links, said links being associated with data identifying units;
• a determinator operable to determine for at least part of the lattice structure defined by lattice data received by said receiver a plurality of areas having edges and vertices defined by the nodes and links of at least part of said lattice structure;
• a generator operable to generate for said areas determined by said determinator, data identifying the number of links bounding each area and data identifying the location of said areas within at least part of said lattice structure;
• and
• an output unit operable to output as recognition data:
• data identifying said units associated with links and said data defining areas.

Apparatus for generating data defining a speech lattice comprising:

• a receiver operable to receive data defining a first speech lattice comprising a plurality of nodes interconnected by links, said links being associated with data identifying speech units;
• a processing unit operable to process data received by said receiver to determine a second speech lattice comprising a planar graph having a number of nodes interconnected by links where none of the links cross, said links being associated with data identifying speech units, the nodes and links of said planar graph defining vertices and edges of areas in a two dimensional plane;
• a generator operable to generate as data defining a planar graph determined by said processing unit, identifying data identifying the number of links bounding each said area defined by said planar graph and the location of said areas within said planar graph;
• and
• an output unit operable to output as data defining said second speech lattice said identifying data generated by said generator and data identifying speech units associated with links of the planar graph defined by said identifying data received by said receiver.

Apparatus for generating a lattice comprising:

• a receiver operable to receive shape data defining a number of areas in a two dimensional plane having vertices and edges corresponding the nodes and links in a planar graph where none of said links cross;
• and
• items of hypothesis data associating links of the planar graph defined by shape data with data identifying units;
• a generator operable to generate a lattice comprising a plurality of nodes connected via links by:
• determining the planar graph defined by said shape data received by said receiver;
• and
• associating the links of said determined planar graph with units utilising said hypothesis data received by said receiver.

Apparatus for generating data defining a lattice structure comprising:

• a receiver operable to receive data defining a lattice structure comprising a plurality of nodes interconnected by links;
• a processing unit operable to process data received by said receiver to determine the differences between an embedding of said lattice structure in a two dimensional plane and a planar graph comprising a number of nodes interconnected by links where none of the links cross, the nodes and links of said planar graph defining edges and vertices of areas in a two dimensional plane;
• a difference generator operable to generate difference data identifying differences;
• a shape encoder operable to generate for said areas of a two dimensional plane defined by a planar graph, identifying data identifying the number of links bounding each said area and data identifying of the location of the said area within said planar graph;
• and
• an output unit operable to output as data defining said lattice structure, said identifying data generated by said shape encoder and said difference data generated by said difference generator.