ilbc.c

基于sip协议的网络电话源码

/* $Id: ilbc.c 974 2007-02-19 01:13:53Z bennylp $ */
/* 
 * Copyright (C)2003-2007 Benny Prijono <[e-mail]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA 
 */
#include <pjmedia-codec/ilbc.h>
#include <pjmedia-codec/types.h>
#include <pjmedia/codec.h>
#include <pjmedia/errno.h>
#include <pjmedia/endpoint.h>
#include <pjmedia/plc.h>
#include <pjmedia/port.h>
#include <pjmedia/silencedet.h>
#include <pj/assert.h>
#include <pj/log.h>
#include <pj/pool.h>
#include <pj/string.h>
#include <pj/os.h>
#include "ilbc/iLBC_encode.h"
#include "ilbc/iLBC_decode.h"


/*
 * Only build this file if PJMEDIA_HAS_ILBC_CODEC != 0
 */
#if defined(PJMEDIA_HAS_ILBC_CODEC) && PJMEDIA_HAS_ILBC_CODEC != 0


#define THIS_FILE	"ilbc.c"
#define CLOCK_RATE	8000
#define DEFAULT_MODE	30


/* Prototypes for iLBC factory */
static pj_status_t ilbc_test_alloc(pjmedia_codec_factory *factory, 
				   const pjmedia_codec_info *id );
static pj_status_t ilbc_default_attr(pjmedia_codec_factory *factory, 
				     const pjmedia_codec_info *id, 
				     pjmedia_codec_param *attr );
static pj_status_t ilbc_enum_codecs(pjmedia_codec_factory *factory, 
				    unsigned *count, 
				    pjmedia_codec_info codecs[]);
static pj_status_t ilbc_alloc_codec(pjmedia_codec_factory *factory, 
				    const pjmedia_codec_info *id, 
				    pjmedia_codec **p_codec);
static pj_status_t ilbc_dealloc_codec(pjmedia_codec_factory *factory, 
				      pjmedia_codec *codec );

/* Prototypes for iLBC implementation. */
static pj_status_t  ilbc_codec_init(pjmedia_codec *codec, 
				    pj_pool_t *pool );
static pj_status_t  ilbc_codec_open(pjmedia_codec *codec, 
				    pjmedia_codec_param *attr );
static pj_status_t  ilbc_codec_close(pjmedia_codec *codec );
static pj_status_t  ilbc_codec_modify(pjmedia_codec *codec, 
				      const pjmedia_codec_param *attr );
static pj_status_t  ilbc_codec_parse(pjmedia_codec *codec,
				     void *pkt,
				     pj_size_t pkt_size,
				     const pj_timestamp *ts,
				     unsigned *frame_cnt,
				     pjmedia_frame frames[]);
static pj_status_t  ilbc_codec_encode(pjmedia_codec *codec, 
				      const struct pjmedia_frame *input,
				      unsigned output_buf_len, 
				      struct pjmedia_frame *output);
static pj_status_t  ilbc_codec_decode(pjmedia_codec *codec, 
				      const struct pjmedia_frame *input,
				      unsigned output_buf_len, 
				      struct pjmedia_frame *output);
static pj_status_t  ilbc_codec_recover(pjmedia_codec *codec,
				       unsigned output_buf_len,
				       struct pjmedia_frame *output);

/* Definition for iLBC codec operations. */
static pjmedia_codec_op ilbc_op = 
{
    &ilbc_codec_init,
    &ilbc_codec_open,
    &ilbc_codec_close,
    &ilbc_codec_modify,
    &ilbc_codec_parse,
    &ilbc_codec_encode,
    &ilbc_codec_decode,
    &ilbc_codec_recover
};

/* Definition for iLBC codec factory operations. */
static pjmedia_codec_factory_op ilbc_factory_op =
{
    &ilbc_test_alloc,
    &ilbc_default_attr,
    &ilbc_enum_codecs,
    &ilbc_alloc_codec,
    &ilbc_dealloc_codec
};

/* iLBC factory */
static struct ilbc_factory
{
    pjmedia_codec_factory    base;
    pjmedia_endpt	    *endpt;

    int			     mode;
    int			     bps;
} ilbc_factory;


/* iLBC codec private data. */
struct ilbc_codec
{
    pjmedia_codec	 base;
    pj_pool_t		*pool;
    char		 obj_name[PJ_MAX_OBJ_NAME];
    pjmedia_silence_det	*vad;
    pj_bool_t		 vad_enabled;
    pj_bool_t		 plc_enabled;
    pj_timestamp	 last_tx;

    pj_bool_t		 enc_ready;
    iLBC_Enc_Inst_t	 enc;
    unsigned		 enc_frame_size;
    unsigned		 enc_samples_per_frame;
    float		 enc_block[BLOCKL_MAX];

    pj_bool_t		 dec_ready;
    iLBC_Dec_Inst_t	 dec;
    unsigned		 dec_frame_size;
    unsigned		 dec_samples_per_frame;
    float		 dec_block[BLOCKL_MAX];
};



/*
 * Initialize and register iLBC codec factory to pjmedia endpoint.
 */
PJ_DEF(pj_status_t) pjmedia_codec_ilbc_init( pjmedia_endpt *endpt,
					     int mode )
{
    pjmedia_codec_mgr *codec_mgr;
    pj_status_t status;

    PJ_ASSERT_RETURN(endpt != NULL, PJ_EINVAL);
    PJ_ASSERT_RETURN(mode==0 || mode==20 || mode==30, PJ_EINVAL);

    /* Create iLBC codec factory. */
    ilbc_factory.base.op = &ilbc_factory_op;
    ilbc_factory.base.factory_data = NULL;
    ilbc_factory.endpt = endpt;

    if (mode == 0)
	mode = DEFAULT_MODE;

    ilbc_factory.mode = mode;

    if (mode == 20) {
	ilbc_factory.bps = 15200;	
    } else {
	ilbc_factory.bps = 13333;
    }

    /* Get the codec manager. */
    codec_mgr = pjmedia_endpt_get_codec_mgr(endpt);
    if (!codec_mgr)
	return PJ_EINVALIDOP;

    /* Register codec factory to endpoint. */
    status = pjmedia_codec_mgr_register_factory(codec_mgr, 
						&ilbc_factory.base);
    if (status != PJ_SUCCESS)
	return status;


    /* Done. */
    return PJ_SUCCESS;
}



/*
 * Unregister iLBC codec factory from pjmedia endpoint and deinitialize
 * the iLBC codec library.
 */
PJ_DEF(pj_status_t) pjmedia_codec_ilbc_deinit(void)
{
    pjmedia_codec_mgr *codec_mgr;
    pj_status_t status;


    /* Get the codec manager. */
    codec_mgr = pjmedia_endpt_get_codec_mgr(ilbc_factory.endpt);
    if (!codec_mgr)
	return PJ_EINVALIDOP;

    /* Unregister iLBC codec factory. */
    status = pjmedia_codec_mgr_unregister_factory(codec_mgr,
						  &ilbc_factory.base);
    
    return status;
}

/* 
 * Check if factory can allocate the specified codec. 
 */
static pj_status_t ilbc_test_alloc( pjmedia_codec_factory *factory, 
				   const pjmedia_codec_info *info )
{
    const pj_str_t ilbc_tag = { "iLBC", 4};

    PJ_UNUSED_ARG(factory);
    PJ_ASSERT_RETURN(factory==&ilbc_factory.base, PJ_EINVAL);


    /* Type MUST be audio. */
    if (info->type != PJMEDIA_TYPE_AUDIO)
	return PJMEDIA_CODEC_EUNSUP;

    /* Check encoding name. */
    if (pj_stricmp(&info->encoding_name, &ilbc_tag) != 0)
	return PJMEDIA_CODEC_EUNSUP;

    /* Check clock-rate */
    if (info->clock_rate != CLOCK_RATE)
	return PJMEDIA_CODEC_EUNSUP;
    
    /* Channel count must be one */
    if (info->channel_cnt != 1)
	return PJMEDIA_CODEC_EUNSUP;

    /* Yes, this should be iLBC! */
    return PJ_SUCCESS;
}


/*
 * Generate default attribute.
 */
static pj_status_t ilbc_default_attr (pjmedia_codec_factory *factory, 
				      const pjmedia_codec_info *id, 
				      pjmedia_codec_param *attr )
{
    PJ_UNUSED_ARG(factory);
    PJ_ASSERT_RETURN(factory==&ilbc_factory.base, PJ_EINVAL);

    PJ_UNUSED_ARG(id);
    PJ_ASSERT_RETURN(pj_stricmp2(&id->encoding_name, "iLBC")==0, PJ_EINVAL);

    pj_bzero(attr, sizeof(pjmedia_codec_param));

    attr->info.clock_rate = CLOCK_RATE;
    attr->info.channel_cnt = 1;
    attr->info.avg_bps = ilbc_factory.bps;
    attr->info.pcm_bits_per_sample = 16;
    attr->info.frm_ptime = (short)ilbc_factory.mode;
    attr->info.pt = PJMEDIA_RTP_PT_ILBC;

    attr->setting.frm_per_pkt = 1;
    attr->setting.vad = 1;
    attr->setting.plc = 1;
    attr->setting.penh = 1;
    attr->setting.dec_fmtp_mode = (pj_uint8_t)ilbc_factory.mode;

    return PJ_SUCCESS;
}

/*
 * Enum codecs supported by this factory (i.e. only iLBC!).
 */
static pj_status_t ilbc_enum_codecs(pjmedia_codec_factory *factory, 
				    unsigned *count, 
				    pjmedia_codec_info codecs[])
{
    PJ_UNUSED_ARG(factory);
    PJ_ASSERT_RETURN(factory==&ilbc_factory.base, PJ_EINVAL);

    PJ_ASSERT_RETURN(codecs && *count > 0, PJ_EINVAL);

    pj_bzero(&codecs[0], sizeof(pjmedia_codec_info));

    codecs[0].encoding_name = pj_str("iLBC");
    codecs[0].pt = PJMEDIA_RTP_PT_ILBC;
    codecs[0].type = PJMEDIA_TYPE_AUDIO;
    codecs[0].clock_rate = 8000;
    codecs[0].channel_cnt = 1;

    *count = 1;

    return PJ_SUCCESS;
}

/*
 * Allocate a new iLBC codec instance.
 */
static pj_status_t ilbc_alloc_codec(pjmedia_codec_factory *factory, 
				    const pjmedia_codec_info *id,
				    pjmedia_codec **p_codec)
{
    pj_pool_t *pool;
    struct ilbc_codec *codec;

    PJ_ASSERT_RETURN(factory && id && p_codec, PJ_EINVAL);
    PJ_ASSERT_RETURN(factory == &ilbc_factory.base, PJ_EINVAL);

    pool = pjmedia_endpt_create_pool(ilbc_factory.endpt, "iLBC%p",