Resampling Algorithm

Sample rate conversion algorithm. More...

Typedefs
typedef struct pjmedia_resample	pjmedia_resample

Functions
pj_status_t	pjmedia_resample_create (pj_pool_t *pool, pj_bool_t high_quality, pj_bool_t large_filter, unsigned channel_count, unsigned rate_in, unsigned rate_out, unsigned samples_per_frame, pjmedia_resample **p_resample)
void	pjmedia_resample_run (pjmedia_resample *resample, const pj_int16_t *input, pj_int16_t *output)
unsigned	pjmedia_resample_get_input_size (pjmedia_resample *resample)
void	pjmedia_resample_destroy (pjmedia_resample *resample)

Detailed Description

This section describes the base resampling functions. In addition to this, application can use the Resample Port which provides media port abstraction for the base resampling algorithm.

Typedef Documentation

pjmedia_resample

typedef struct pjmedia_resample pjmedia_resample

Opaque resample session.

Function Documentation

pjmedia_resample_create()

pj_status_t pjmedia_resample_create	(	pj_pool_t *	pool,
		pj_bool_t	high_quality,
		pj_bool_t	large_filter,
		unsigned	channel_count,
		unsigned	rate_in,
		unsigned	rate_out,
		unsigned	samples_per_frame,
		pjmedia_resample **	p_resample
	)

Create a frame based resample session.

Parameters

pool	Pool to allocate the structure and buffers.
high_quality	If true, then high quality conversion will be used, at the expense of more CPU and memory, because temporary buffer needs to be created.
large_filter	If true, large filter size will be used.
channel_count	Number of channels.
rate_in	Clock rate of the input samples.
rate_out	Clock rate of the output samples.
samples_per_frame	Number of samples per frame in the input.
p_resample	Pointer to receive the resample session.

Returns

PJ_SUCCESS on success.

pjmedia_resample_run()

void pjmedia_resample_run	(	pjmedia_resample *	resample,
		const pj_int16_t *	input,
		pj_int16_t *	output
	)

Use the resample session to resample a frame. The frame must have the same size and settings as the resample session, or otherwise the behavior is undefined.

Parameters

resample	The resample session.
input	Buffer containing the input samples.
output	Buffer to store the output samples.

pjmedia_resample_get_input_size()

unsigned pjmedia_resample_get_input_size

(

pjmedia_resample *

resample

)

Get the input frame size of a resample session.

Parameters

resample

The resample session.

Returns

The frame size, in number of samples.

pjmedia_resample_destroy()

void pjmedia_resample_destroy

(

pjmedia_resample *

resample

)

Destroy the resample.

Parameters

resample

The resample session.