gapk/libgsmhr/libgsmhr.c

146 lines
3.0 KiB
C

/* HR (GSM 06.20) codec wrapper */
/*
* This file is part of gapk (GSM Audio Pocket Knife).
*
* gapk 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 3 of the License, or
* (at your option) any later version.
*
* gapk 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 gapk. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <dlfcn.h>
#include <gsmhr/gsmhr.h>
#include "refsrc/typedefs.h"
#include "refsrc/homing.h"
#include "refsrc/sp_dec.h"
#include "refsrc/sp_enc.h"
#define EXPORT __attribute__((visibility("default")))
struct gsmhr {
int dec_reset_flg;
void *bss_base;
void *bss_save;
unsigned bss_len;
};
EXPORT struct gsmhr *
gsmhr_init(void)
{
struct gsmhr *state;
void *lib;
lib = dlopen("libgsmhr.so.0", RTLD_NOW | RTLD_NOLOAD);
if (!lib)
return NULL;
state = calloc(1, sizeof(struct gsmhr));
if (!state)
return NULL;
state->dec_reset_flg = 1;
state->bss_base = dlsym(lib, "__bss_start");
state->bss_len = dlsym(lib, "_end") - state->bss_base;
state->bss_save = malloc(state->bss_len);
if (!state->bss_save)
{
free(state);
return NULL;
}
resetDec();
resetEnc();
memcpy(state->bss_save, state->bss_base, state->bss_len);
return state;
}
EXPORT void
gsmhr_exit(struct gsmhr *state)
{
free(state->bss_save);
free(state);
}
EXPORT int
gsmhr_encode(struct gsmhr *state, int16_t *hr_params, const int16_t *pcm)
{
int enc_reset_flg;
Shortword pcm_b[F_LEN];
memcpy(state->bss_base, state->bss_save, state->bss_len);
memcpy(pcm_b, pcm, F_LEN*sizeof(int16_t));
enc_reset_flg = encoderHomingFrameTest(pcm_b);
speechEncoder(pcm_b, hr_params);
if (enc_reset_flg)
resetEnc();
memcpy(state->bss_save, state->bss_base, state->bss_len);
return 0;
}
EXPORT int
gsmhr_decode(struct gsmhr *state, int16_t *pcm, const int16_t *hr_params)
{
#define WHOLE_FRAME 18
#define TO_FIRST_SUBFRAME 9
int dec_reset_flg;
Shortword hr_params_b[22];
memcpy(state->bss_base, state->bss_save, state->bss_len);
memcpy(hr_params_b, hr_params, 22*sizeof(int16_t));
if (state->dec_reset_flg)
dec_reset_flg = decoderHomingFrameTest(hr_params_b, TO_FIRST_SUBFRAME);
else
dec_reset_flg = 0;
if (dec_reset_flg && state->dec_reset_flg) {
int i;
for (i=0; i<F_LEN; i++)
pcm[i] = EHF_MASK;
} else {
speechDecoder(hr_params_b, pcm);
}
if (!state->dec_reset_flg)
dec_reset_flg = decoderHomingFrameTest(hr_params_b, WHOLE_FRAME);
if (dec_reset_flg)
resetDec();
state->dec_reset_flg = dec_reset_flg;
memcpy(state->bss_save, state->bss_base, state->bss_len);
return 0;
}