Alexandre Lision | 8af73cb | 2013-12-10 14:11:20 -0500 | [diff] [blame] | 1 | /* $Id$ */ |
| 2 | /* |
| 3 | * Copyright (C) 2008-2011 Teluu Inc. (http://www.teluu.com) |
| 4 | * Copyright (C) 2003-2008 Benny Prijono <benny@prijono.org> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License as published by |
| 8 | * the Free Software Foundation; either version 2 of the License, or |
| 9 | * (at your option) any later version. |
| 10 | * |
| 11 | * This program is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | * GNU General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU General Public License |
| 17 | * along with this program; if not, write to the Free Software |
| 18 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 19 | */ |
| 20 | #include <pjmedia/plc.h> |
| 21 | #include <pjmedia/errno.h> |
| 22 | #include <pjmedia/wsola.h> |
| 23 | #include <pj/assert.h> |
| 24 | #include <pj/pool.h> |
| 25 | #include <pj/string.h> |
| 26 | |
| 27 | |
| 28 | static void* plc_wsola_create(pj_pool_t*, unsigned c, unsigned f); |
| 29 | static void plc_wsola_save(void*, pj_int16_t*); |
| 30 | static void plc_wsola_generate(void*, pj_int16_t*); |
| 31 | |
| 32 | /** |
| 33 | * This struct is used internally to represent a PLC backend. |
| 34 | */ |
| 35 | struct plc_alg |
| 36 | { |
| 37 | void* (*plc_create)(pj_pool_t*, unsigned c, unsigned f); |
| 38 | void (*plc_save)(void*, pj_int16_t*); |
| 39 | void (*plc_generate)(void*, pj_int16_t*); |
| 40 | }; |
| 41 | |
| 42 | |
| 43 | static struct plc_alg plc_wsola = |
| 44 | { |
| 45 | &plc_wsola_create, |
| 46 | &plc_wsola_save, |
| 47 | &plc_wsola_generate |
| 48 | }; |
| 49 | |
| 50 | |
| 51 | struct pjmedia_plc |
| 52 | { |
| 53 | void *obj; |
| 54 | struct plc_alg *op; |
| 55 | }; |
| 56 | |
| 57 | |
| 58 | /* |
| 59 | * Create PLC session. This function will select the PLC algorithm to |
| 60 | * use based on the arguments. |
| 61 | */ |
| 62 | PJ_DEF(pj_status_t) pjmedia_plc_create( pj_pool_t *pool, |
| 63 | unsigned clock_rate, |
| 64 | unsigned samples_per_frame, |
| 65 | unsigned options, |
| 66 | pjmedia_plc **p_plc) |
| 67 | { |
| 68 | pjmedia_plc *plc; |
| 69 | |
| 70 | PJ_ASSERT_RETURN(pool && clock_rate && samples_per_frame && p_plc, |
| 71 | PJ_EINVAL); |
| 72 | PJ_ASSERT_RETURN(options == 0, PJ_EINVAL); |
| 73 | |
| 74 | PJ_UNUSED_ARG(options); |
| 75 | |
| 76 | plc = PJ_POOL_ZALLOC_T(pool, pjmedia_plc); |
| 77 | |
| 78 | plc->op = &plc_wsola; |
| 79 | plc->obj = plc->op->plc_create(pool, clock_rate, samples_per_frame); |
| 80 | |
| 81 | *p_plc = plc; |
| 82 | |
| 83 | return PJ_SUCCESS; |
| 84 | } |
| 85 | |
| 86 | |
| 87 | /* |
| 88 | * Save a good frame to PLC. |
| 89 | */ |
| 90 | PJ_DEF(pj_status_t) pjmedia_plc_save( pjmedia_plc *plc, |
| 91 | pj_int16_t *frame ) |
| 92 | { |
| 93 | PJ_ASSERT_RETURN(plc && frame, PJ_EINVAL); |
| 94 | |
| 95 | plc->op->plc_save(plc->obj, frame); |
| 96 | return PJ_SUCCESS; |
| 97 | } |
| 98 | |
| 99 | |
| 100 | /* |
| 101 | * Generate a replacement for lost frame. |
| 102 | */ |
| 103 | PJ_DEF(pj_status_t) pjmedia_plc_generate( pjmedia_plc *plc, |
| 104 | pj_int16_t *frame ) |
| 105 | { |
| 106 | PJ_ASSERT_RETURN(plc && frame, PJ_EINVAL); |
| 107 | |
| 108 | plc->op->plc_generate(plc->obj, frame); |
| 109 | return PJ_SUCCESS; |
| 110 | } |
| 111 | |
| 112 | |
| 113 | ////////////////////////////////////////////////////////////////////////////// |
| 114 | /* |
| 115 | * Packet loss concealment based on WSOLA |
| 116 | */ |
| 117 | struct wsola_plc |
| 118 | { |
| 119 | pjmedia_wsola *wsola; |
| 120 | pj_bool_t prev_lost; |
| 121 | }; |
| 122 | |
| 123 | |
| 124 | static void* plc_wsola_create(pj_pool_t *pool, unsigned clock_rate, |
| 125 | unsigned samples_per_frame) |
| 126 | { |
| 127 | struct wsola_plc *o; |
| 128 | unsigned flag; |
| 129 | pj_status_t status; |
| 130 | |
| 131 | PJ_UNUSED_ARG(clock_rate); |
| 132 | |
| 133 | o = PJ_POOL_ZALLOC_T(pool, struct wsola_plc); |
| 134 | o->prev_lost = PJ_FALSE; |
| 135 | |
| 136 | flag = PJMEDIA_WSOLA_NO_DISCARD; |
| 137 | if (PJMEDIA_WSOLA_PLC_NO_FADING) |
| 138 | flag |= PJMEDIA_WSOLA_NO_FADING; |
| 139 | |
| 140 | status = pjmedia_wsola_create(pool, clock_rate, samples_per_frame, 1, |
| 141 | flag, &o->wsola); |
| 142 | if (status != PJ_SUCCESS) |
| 143 | return NULL; |
| 144 | |
| 145 | return o; |
| 146 | } |
| 147 | |
| 148 | static void plc_wsola_save(void *plc, pj_int16_t *frame) |
| 149 | { |
| 150 | struct wsola_plc *o = (struct wsola_plc*) plc; |
| 151 | |
| 152 | pjmedia_wsola_save(o->wsola, frame, o->prev_lost); |
| 153 | o->prev_lost = PJ_FALSE; |
| 154 | } |
| 155 | |
| 156 | static void plc_wsola_generate(void *plc, pj_int16_t *frame) |
| 157 | { |
| 158 | struct wsola_plc *o = (struct wsola_plc*) plc; |
| 159 | |
| 160 | pjmedia_wsola_generate(o->wsola, frame); |
| 161 | o->prev_lost = PJ_TRUE; |
| 162 | } |
| 163 | |
| 164 | |