ad.h File Reference

generic live audio interface for recording and playback More...

#include <sphinx_config.h>
#include <sphinxbase/sphinxbase_export.h>
#include <sphinxbase/prim_type.h>

Go to the source code of this file.

Data Structures
struct	ad_rec_t
struct	ad_play_t

Macros
#define	AD_SAMPLE_SIZE   (sizeof(int16))
#define	DEFAULT_SAMPLES_PER_SEC   16000
#define	AD_OK   0
#define	AD_EOF   -1
#define	AD_ERR_GEN   -1
#define	AD_ERR_NOT_OPEN   -2
#define	AD_ERR_WAVE   -3
#define	DEFAULT_DEVICE   NULL

Functions
SPHINXBASE_EXPORT ad_rec_t *	ad_open_dev (const char *dev, int32 samples_per_sec)
	Open a specific audio device for recording.
SPHINXBASE_EXPORT ad_rec_t *	ad_open_sps (int32 samples_per_sec)
	Open the default audio device with a given sampling rate.
SPHINXBASE_EXPORT ad_rec_t *	ad_open (void)
	Open the default audio device.
SPHINXBASE_EXPORT int32	ad_start_rec (ad_rec_t *)
SPHINXBASE_EXPORT int32	ad_stop_rec (ad_rec_t *)
SPHINXBASE_EXPORT int32	ad_close (ad_rec_t *)
SPHINXBASE_EXPORT int32	ad_read (ad_rec_t *, int16 *buf, int32 max)
SPHINXBASE_EXPORT ad_play_t *	ad_open_play_sps (int32 samples_per_sec)
SPHINXBASE_EXPORT ad_play_t *	ad_open_play (void)
SPHINXBASE_EXPORT int32	ad_start_play (ad_play_t *)
SPHINXBASE_EXPORT int32	ad_stop_play (ad_play_t *)
SPHINXBASE_EXPORT int32	ad_close_play (ad_play_t *)
SPHINXBASE_EXPORT int32	ad_write (ad_play_t *, int16 *buf, int32 len)
	Queue a block of audio samples for playback.
SPHINXBASE_EXPORT void	ad_mu2li (int16 *outbuf, unsigned char *inbuf, int32 n_samp)
	Convert mu-law data to int16 linear PCM format.

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Detailed Description

generic live audio interface for recording and playback

Definition in file ad.h.

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Function Documentation

SPHINXBASE_EXPORT ad_rec_t* ad_open_dev	(	const char *	dev,
		int32	samples_per_sec
	)

Open a specific audio device for recording.

The device is opened in non-blocking mode and placed in idle state.

Returns:

pointer to read-only ad_rec_t structure if successful, NULL otherwise. The return value to be used as the first argument to other recording functions.

Parameters:

dev	Device name (platform-specific)
samples_per_sec	Samples per second

Definition at line 252 of file ad_alsa.c.

References ad_open_dev(), ad_rec_t::bps, and ad_rec_t::sps.

Referenced by ad_open_dev(), and ad_open_sps().

SPHINXBASE_EXPORT ad_rec_t* ad_open_sps

(

int32

samples_per_sec

)

Open the default audio device with a given sampling rate.

Parameters:

samples_per_sec

Samples per second

Definition at line 290 of file ad_alsa.c.

References ad_open_dev(), and ad_open_sps().

Referenced by ad_open(), and ad_open_sps().

SPHINXBASE_EXPORT int32 ad_write	(	ad_play_t *	,
		int16 *	buf,
		int32	len
	)

Queue a block of audio samples for playback.

Write the next block of [len] samples from rawbuf to the A/D device for playback. The device may queue less than len samples, possibly 0, since it is non-blocking. The application should resubmit the remaining data to be played. Return value: # samples accepted for playback; -1 if error.

Definition at line 373 of file play_win32.c.

References ad_write().

Referenced by ad_write().