include/pv_rhino.h File Reference

#include <stdbool.h>
#include <stdint.h>
#include "picovoice.h"

Include dependency graph for include/pv_rhino.h:

Go to the source code of this file.

Typedefs
typedef struct pv_rhino	pv_rhino_t

Functions
PV_API pv_status_t	pv_rhino_context_info (const pv_rhino_t *object, const char **context_info)
PV_API void	pv_rhino_delete (pv_rhino_t *object)
PV_API int32_t	pv_rhino_frame_length (void)
PV_API pv_status_t	pv_rhino_free_slots_and_values (const pv_rhino_t *object, const char **slots, const char **values)
PV_API pv_status_t	pv_rhino_get_intent (const pv_rhino_t *object, const char **intent, int32_t *num_slots, const char ***slots, const char ***values)
PV_API pv_status_t	pv_rhino_init (const char *access_key, const char *model_path, const char *context_path, float sensitivity, bool require_endpoint, pv_rhino_t **object)
PV_API pv_status_t	pv_rhino_is_understood (const pv_rhino_t *object, bool *is_understood)
PV_API pv_status_t	pv_rhino_process (pv_rhino_t *object, const int16_t *pcm, bool *is_finalized)
PV_API pv_status_t	pv_rhino_reset (pv_rhino_t *object)
const PV_API char *	pv_rhino_version (void)

Typedef Documentation

pv_rhino_t

typedef struct pv_rhino pv_rhino_t

Forward declaration for Rhino Speech-to-Intent engine. It directly infers the user's intent from spoken commands in real-time. Rhino processes incoming audio in consecutive frames and indicates if the inference is finalized. When finalized, the inferred intent can be retrieved as structured data in the form of an intent string and pairs of slots and values. The number of samples per frame can be attained by calling 'pv_rhino_frame_length()'. The incoming audio needs to have a sample rate equal to 'pv_sample_rate()' and be 16-bit linearly-encoded. Rhino operates on single-channel audio.

Definition at line 34 of file include/pv_rhino.h.

Function Documentation

pv_rhino_context_info()

PV_API pv_status_t pv_rhino_context_info	(	const pv_rhino_t *	object,
		const char **	context_info
	)

Getter for context information.

Parameters

	object	Speech-to-Intent object.
[out]	context_info	Context information.

Returns

Status code. Returns 'PV_STATUS_INVALID_ARGUMENT' on failure.

pv_rhino_delete()

PV_API void pv_rhino_delete

(

pv_rhino_t *

object

)

Destructor.

Parameters

object

Speech-to-Intent object.

pv_rhino_frame_length()

PV_API int32_t pv_rhino_frame_length

(

void

)

Getter for number of audio samples per frame.

Returns

Frame length.

pv_rhino_free_slots_and_values()

PV_API pv_status_t pv_rhino_free_slots_and_values	(	const pv_rhino_t *	object,
		const char **	slots,
		const char **	values
	)

Frees memory resources allocated to slots and values after calling 'pv_rhino_get_intent()'. One shouldn't free these resources via standard C library 'free()'.

Parameters

object	Speech-to-Intent object.
slots	Slots.
values	Slot values.

Returns

Returns 'PV_STATUS_INVALID_ARGUMENT' on failure.

pv_rhino_get_intent()

PV_API pv_status_t pv_rhino_get_intent	(	const pv_rhino_t *	object,
		const char **	intent,
		int32_t *	num_slots,
		const char ***	slots,
		const char ***	values
	)

Getter for the intent. The intent is stored as an intent string and pairs of slots and values. It should be called only after intent inference is finalized and it is verified that the spoken command is understood via calling 'pv_rhino_is_understood()'.

Parameters

	object	Speech-to-Intent object.
[out]	intent	Inferred intent.
[out]	num_slots	Number of slots.
[out]	slots	Array of inferred slots. Its memory needs to be freed by calling 'pv_rhino_free_slots_and_values()'.
[out]	values	Array of inferred slot values. Its memory needs to be freed by calling 'pv_rhino_free_slots_and_values()'.

Returns

State code. Returns 'PV_STATUS_INVALID_ARGUMENT', 'PV_STATUS_INVALID_STATE', or 'PV_STATUS_OUT_OF_MEMORY' on failure.

pv_rhino_init()

PV_API pv_status_t pv_rhino_init	(	const char *	access_key,
		const char *	model_path,
		const char *	context_path,
		float	sensitivity,
		bool	require_endpoint,
		pv_rhino_t **	object
	)

Constructor.

Parameters

	access_key	AccessKey obtained from Picovoice Console (https://console.picovoice.ai/).
	model_path	Absolute path to file containing model parameters.
	context_path	Absolute path to file containing context parameters. A context represents the set of expressions (spoken commands), intents, and intent arguments (slots) within a domain of interest.
	sensitivity	Inference sensitivity. It should be a number within [0, 1]. A higher sensitivity value results in fewer misses at the cost of (potentially) increasing the erroneous inference rate.
	require_endpoint	If set to true, Rhino requires an endpoint (chunk of silence) before finishing inference.
[out]	object	Constructed Speech-to-Intent object.

Returns

Status code. Returns 'PV_STATUS_INVALID_ARGUMENT', 'PV_STATUS_IO_ERROR', or 'PV_STATUS_OUT_OF_MEMORY' on failure.

pv_rhino_is_understood()

PV_API pv_status_t pv_rhino_is_understood	(	const pv_rhino_t *	object,
		bool *	is_understood
	)

Indicates if the spoken command is valid, is within the domain of interest (context), and the engine understood it. Upon success 'pv_rhino_get_intent()' may be called to retrieve inferred intent. If not understood, 'pv_rhino_reset()' should be called.

Parameters

	object	Speech-to-Intent object.
[out]	is_understood	Flag indicating if the spoken command is understood.

Returns

Status code. Returns 'PV_STATUS_INVALID_ARGUMENT' on failure.

pv_rhino_process()

PV_API pv_status_t pv_rhino_process	(	pv_rhino_t *	object,
		const int16_t *	pcm,
		bool *	is_finalized
	)

Processes a frame of audio and emits a flag indicating if the inference is finalized. When finalized, 'pv_rhino_is_understood()' should be called to check if the spoken command is considered valid.

Parameters

	object	Speech-to-Intent object.
	pcm	A frame of audio samples. The number of samples per frame can be attained by calling 'pv_rhino_frame_length()'. The incoming audio needs to have a sample rate equal to 'pv_sample_rate()' and be 16-bit linearly-encoded. Rhino operates on single-channel audio.
[out]	is_finalized	Flag indicating if the inference is finalized.

Returns

Status code. Returns 'PV_STATUS_INVALID_ARGUMENT' or 'PV_STATUS_OUT_OF_MEMORY' on failure.

pv_rhino_reset()

PV_API pv_status_t pv_rhino_reset

(

pv_rhino_t *

object

)

Resets the internal state of the engine. It should be called before the engine can be used to infer intent from a new stream of audio.

Parameters

object

Speech-to-Intent object.

Returns

Status code. Returns 'PV_STATUS_INVALID_ARGUMENT' on failure.

pv_rhino_version()

const PV_API char* pv_rhino_version

(

void

)

Getter for version.

Returns

Version.