diff options
Diffstat (limited to 'pjmedia/src/pjmedia/plc_common.c')
| -rw-r--r-- | pjmedia/src/pjmedia/plc_common.c | 164 |
1 files changed, 164 insertions, 0 deletions
diff --git a/pjmedia/src/pjmedia/plc_common.c b/pjmedia/src/pjmedia/plc_common.c new file mode 100644 index 0000000..6849836 --- /dev/null +++ b/pjmedia/src/pjmedia/plc_common.c @@ -0,0 +1,164 @@ +/* $Id: plc_common.c 3553 2011-05-05 06:14:19Z nanang $ */ +/* + * Copyright (C) 2008-2011 Teluu Inc. (http://www.teluu.com) + * Copyright (C) 2003-2008 Benny Prijono <benny@prijono.org> + * + * 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/plc.h> +#include <pjmedia/errno.h> +#include <pjmedia/wsola.h> +#include <pj/assert.h> +#include <pj/pool.h> +#include <pj/string.h> + + +static void* plc_wsola_create(pj_pool_t*, unsigned c, unsigned f); +static void plc_wsola_save(void*, pj_int16_t*); +static void plc_wsola_generate(void*, pj_int16_t*); + +/** + * This struct is used internally to represent a PLC backend. + */ +struct plc_alg +{ + void* (*plc_create)(pj_pool_t*, unsigned c, unsigned f); + void (*plc_save)(void*, pj_int16_t*); + void (*plc_generate)(void*, pj_int16_t*); +}; + + +static struct plc_alg plc_wsola = +{ + &plc_wsola_create, + &plc_wsola_save, + &plc_wsola_generate +}; + + +struct pjmedia_plc +{ + void *obj; + struct plc_alg *op; +}; + + +/* + * Create PLC session. This function will select the PLC algorithm to + * use based on the arguments. + */ +PJ_DEF(pj_status_t) pjmedia_plc_create( pj_pool_t *pool, + unsigned clock_rate, + unsigned samples_per_frame, + unsigned options, + pjmedia_plc **p_plc) +{ + pjmedia_plc *plc; + + PJ_ASSERT_RETURN(pool && clock_rate && samples_per_frame && p_plc, + PJ_EINVAL); + PJ_ASSERT_RETURN(options == 0, PJ_EINVAL); + + PJ_UNUSED_ARG(options); + + plc = PJ_POOL_ZALLOC_T(pool, pjmedia_plc); + + plc->op = &plc_wsola; + plc->obj = plc->op->plc_create(pool, clock_rate, samples_per_frame); + + *p_plc = plc; + + return PJ_SUCCESS; +} + + +/* + * Save a good frame to PLC. + */ +PJ_DEF(pj_status_t) pjmedia_plc_save( pjmedia_plc *plc, + pj_int16_t *frame ) +{ + PJ_ASSERT_RETURN(plc && frame, PJ_EINVAL); + + plc->op->plc_save(plc->obj, frame); + return PJ_SUCCESS; +} + + +/* + * Generate a replacement for lost frame. + */ +PJ_DEF(pj_status_t) pjmedia_plc_generate( pjmedia_plc *plc, + pj_int16_t *frame ) +{ + PJ_ASSERT_RETURN(plc && frame, PJ_EINVAL); + + plc->op->plc_generate(plc->obj, frame); + return PJ_SUCCESS; +} + + +////////////////////////////////////////////////////////////////////////////// +/* + * Packet loss concealment based on WSOLA + */ +struct wsola_plc +{ + pjmedia_wsola *wsola; + pj_bool_t prev_lost; +}; + + +static void* plc_wsola_create(pj_pool_t *pool, unsigned clock_rate, + unsigned samples_per_frame) +{ + struct wsola_plc *o; + unsigned flag; + pj_status_t status; + + PJ_UNUSED_ARG(clock_rate); + + o = PJ_POOL_ZALLOC_T(pool, struct wsola_plc); + o->prev_lost = PJ_FALSE; + + flag = PJMEDIA_WSOLA_NO_DISCARD; + if (PJMEDIA_WSOLA_PLC_NO_FADING) + flag |= PJMEDIA_WSOLA_NO_FADING; + + status = pjmedia_wsola_create(pool, clock_rate, samples_per_frame, 1, + flag, &o->wsola); + if (status != PJ_SUCCESS) + return NULL; + + return o; +} + +static void plc_wsola_save(void *plc, pj_int16_t *frame) +{ + struct wsola_plc *o = (struct wsola_plc*) plc; + + pjmedia_wsola_save(o->wsola, frame, o->prev_lost); + o->prev_lost = PJ_FALSE; +} + +static void plc_wsola_generate(void *plc, pj_int16_t *frame) +{ + struct wsola_plc *o = (struct wsola_plc*) plc; + + pjmedia_wsola_generate(o->wsola, frame); + o->prev_lost = PJ_TRUE; +} + + |