LV_SRE_Decode

Processes the voice channel audio data against the active grammar. This is the manual process of telling the Engine to perform a recognition. The two most common reasons to use this function are to perform off-line decodes on existing audio or to programatically control whether to decode after a streaming process.

Function

• int LV_SRE_Decode(HPORT hport,int VoiceChannel,int GrammarSet,unsigned int flags)

Parameters

hport

The port's handle.

VoiceChannel

The audio channel holding the decode audio.

GrammarSet

The grammar to use for the decode. When using SRGS grammars this value should be set to LV_ACTIVE_GRAMMAR_SET. This tells the decoder to use every SRGS grammar which has been loaded and activated. Other values indicate the Engine should use a concept/phrase grammar set.

flags (bitwise OR flags to set desired options)

LV_DECODE_BLOCK - Decode will not return until it has finished.

LV_DECODE_SEMANTIC_INTERPRETATION - Deprecated

Return Values

Positive Number

A positive number will be returned if you have set LV_DECODE_BLOCK. This number indicates how many interpretations the ASR was able to decode.

LV_SUCCESS

LV_SUCCESS will be returned if the LV_DECODE_BLOCK flag was not set. This return indicates that the port was able to successfully communicate with the server.

LV_ACTIVE_GRAMMAR_INVALID_LANGUAGE

Indicates that the language specified in the grammar is either invalid or is not available on the ASR server.

LV_ACTIVE_GRAMMAR_LANGUAGE_CONFLICT

Indicates that more than one language was specified in the active grammar set.

LV_ACTIVE_GRAMMAR_VOCAB_SIZE_EXCEEDS_LIMIT

Indicates that you do not have the right license type for the decode. Either a Lite license was used when the vocabulary size of the active grammar set exceeded 500, or an SLM decode operation was attempted with a non-SLM license.

LV_BAD_SOUND_DATA

Sound sample was < 1/8 of a second.

LV_FAILURE

This grammar could not be activated, because the port was shutting down.

LV_GRAMMAR_LOADING_ERROR

Indicates an error in using an active grammar for the decode operation (eg: there were no words in the compiled grammar).

LV_INVALID_LICENSE

Indicates License used is not valid.

LV_INVALID_HPORT

The input hport is not a valid one.

LV_INVALID_SOUND_CHANNEL

The input VoiceChannel is not a valid one.

LV_LICENSES_EXPIRED

Indicates that the license acquired for the decode operation does not permit the use of the current version of the ASR server.

LV_NO_SERVER_AVAILABLE

Indicates that no ASR servers were available to perform the decode.

LV_TIME_OUT

Indicates that the preceeding decode operation timed out.

LV_EXCEPTION

An exception occured while processing the request.

When not blocking the function, LV_SRE_GetLastDecodeError should be called to check for additional grammar / language issues which may have occurred during the recognition process.

Remarks

If LV_DECODE_BLOCK is set, LV_SRE_Decode will not return until it has finished processing the data.

If LV_DECODE_BLOCK is not set, LV_SRE_Decode returns immediately (but continues processing the data on a separate thread); the client application can continue its own work. Calling other LVSpeechPort methods may block until the Decode is finished. Once the client application is ready to check for results, call LV_SRE_WaitForEngineToIdle. If any function which requests the results of the decode is called before the result is ready, the function itself will call LV_SRE_WaitForEngineToIdle with an infinite timeout.

On an error, call LV_SRE_ReturnErrorString with the negative result from LV_SRE_Decode or LV_SRE_GetLastDecodeError to get a description of the error.

Of the error codes listed above, LV_INVALID_HPORT and LV_INVALID_SOUND_CHANNEL are returned due to an error in the inputs to the function.

See Also

• LV_SRE_GetLastDecodeError
• LV_SRE_WaitForEngineToIdle
• LVSpeechPort::Decode (C++ API)