The LVSpeechPort DLL exports a set of "C" API functions.  This functionality is wrapped in a C++ class called LVSpeechPort.  Each LVSpeechPort instance represents one speech recognition port and processes its sound data into text; all port instances can process their data in parallel.  If the client application is multi-threaded, every thread that needs to process audio data should have its own LVSpeechPort.

Each port has multiple voice channels and grammar sets.

• Each voice channel holds raw audio data.  Before processing any data, the client application must call LoadVoiceChannel to load the channel.  The channel keeps its own copy of this sound data, so the client application can free its copy after the call to LoadVoiceChannel.  The voice channel will store the data until the client application loads new data into the channel.  This allows the client application to decode the same sound data against different grammars without reloading the data.  
• The Decode method processes a voice channel against a grammar set, returning the concepts from the grammar set recognized in the channel’s audio data.  Multiple voice channels are provided as a convenience, but only one voice channel can decode concurrently per port.

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