[2434] | 1 | //fader.c: |
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| 2 | |
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| 3 | /* |
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| 4 | * Copyright (C) Philipp 'ph3-der-loewe' Schafft - 2009 |
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| 5 | * |
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| 6 | * This file is part of libroardsp a part of RoarAudio, |
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| 7 | * a cross-platform sound system for both, home and professional use. |
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| 8 | * See README for details. |
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| 9 | * |
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| 10 | * This file is free software; you can redistribute it and/or modify |
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| 11 | * it under the terms of the GNU General Public License version 3 |
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| 12 | * as published by the Free Software Foundation. |
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| 13 | * |
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| 14 | * libroardsp is distributed in the hope that it will be useful, |
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| 15 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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| 17 | * GNU General Public License for more details. |
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| 18 | * |
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| 19 | * You should have received a copy of the GNU General Public License |
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| 20 | * along with this software; see the file COPYING. If not, write to |
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| 21 | * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. |
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| 22 | * |
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| 23 | */ |
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| 24 | |
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| 25 | #include "libroardsp.h" |
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| 26 | |
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[2438] | 27 | #define _CHECK_BASIC() if ( state == NULL ) return -1 |
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| 28 | #define _CHECK_CALCPCM() _CHECK_BASIC(); if ( frames == 0 ) return 0; if ( data == NULL ) return -1; |
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| 29 | |
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| 30 | int roar_fader_init (struct roar_fader_state * state, float * poly, int coeff) { |
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| 31 | _CHECK_BASIC(); |
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| 32 | |
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| 33 | if ( poly == NULL ) |
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| 34 | return -1; |
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| 35 | |
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| 36 | if ( coeff < 2 ) |
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| 37 | return -1; |
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| 38 | |
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| 39 | if ( coeff > ROAR_FADER_MAX_COEFF ) |
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| 40 | return -1; |
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| 41 | |
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| 42 | memset(state, 0, sizeof(struct roar_fader_state)); |
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| 43 | |
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| 44 | state->rate = -1; |
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| 45 | state->coeff = coeff; |
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| 46 | |
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[2440] | 47 | state->start = -1; |
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| 48 | state->stop = -1; |
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| 49 | |
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[2443] | 50 | memcpy(state->poly, poly, sizeof(float)*coeff); |
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[2438] | 51 | |
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| 52 | return 0; |
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| 53 | } |
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| 54 | |
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| 55 | int roar_fader_set_rate (struct roar_fader_state * state, int rate) { |
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| 56 | _CHECK_BASIC(); |
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| 57 | |
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| 58 | state->rate = rate; |
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| 59 | |
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| 60 | return 0; |
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| 61 | } |
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| 62 | |
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| 63 | int roar_fader_set_startstop(struct roar_fader_state * state, ssize_t start, ssize_t stop) { |
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| 64 | _CHECK_BASIC(); |
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| 65 | |
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| 66 | if ( start >= 0 ) |
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| 67 | state->start = start; |
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| 68 | |
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| 69 | if ( stop >= 0 ) |
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| 70 | state->stop = stop; |
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| 71 | |
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| 72 | return 0; |
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| 73 | } |
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| 74 | |
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| 75 | int roar_fader_calcpcm_i16n(struct roar_fader_state * state, int16_t * data, size_t frames, int channels) { |
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| 76 | _CHECK_CALCPCM(); |
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| 77 | |
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| 78 | switch (channels) { |
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| 79 | case 1: return roar_fader_calcpcm_i161(state, data, frames); |
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| 80 | } |
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| 81 | |
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| 82 | return -1; |
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| 83 | } |
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| 84 | |
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| 85 | int roar_fader_calcpcm_i161(struct roar_fader_state * state, int16_t * data, size_t frames) { |
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[2441] | 86 | size_t start, stop, cur; |
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| 87 | int i, i_s, i_e; |
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| 88 | float t_cur, t_step; |
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| 89 | float g_cur; |
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| 90 | |
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| 91 | _CHECK_BASIC(); |
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| 92 | |
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| 93 | if ( state->start == -1 ) { |
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| 94 | start = state->pcmoffset; |
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| 95 | } else { |
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| 96 | start = state->start; |
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| 97 | } |
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| 98 | |
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| 99 | if ( state->stop == -1 ) { |
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| 100 | stop = state->pcmoffset + frames; |
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| 101 | } else { |
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| 102 | stop = state->stop; |
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| 103 | } |
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| 104 | |
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| 105 | cur = state->pcmoffset; |
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| 106 | |
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| 107 | i_s = 0; |
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| 108 | i_e = frames; |
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| 109 | |
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| 110 | if ( start > cur ) |
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| 111 | i_s = start - cur; |
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| 112 | |
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| 113 | if ( stop < (cur + frames) ) |
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| 114 | i_e = stop - cur; |
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| 115 | |
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[2443] | 116 | t_step = (float)(state->coeff - 1)/(float)(stop - start); |
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[2441] | 117 | |
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| 118 | if ( start < cur ) { |
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| 119 | t_cur = (cur - start)*t_step; |
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| 120 | } else { |
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| 121 | t_cur = 0; |
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| 122 | } |
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| 123 | |
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[2443] | 124 | ROAR_DBG("roar_fader_calcpcm_i161(*): i_s->i_e: %i->%i", i_s, i_e); |
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| 125 | |
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[2441] | 126 | for (i = i_s; i < i_e; i++, cur++) { |
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| 127 | t_cur += t_step; |
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[2443] | 128 | g_cur = roar_math_cvpoly(state->poly, t_cur, state->coeff); |
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| 129 | // ROAR_DBG("roar_fader_calcpcm_i161(*): i=%i, g_cur=%f", i, g_cur); |
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[2441] | 130 | data[i] = (float)data[i] * g_cur; |
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| 131 | } |
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| 132 | |
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| 133 | state->pcmoffset = cur; |
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| 134 | |
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[2438] | 135 | return -1; |
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| 136 | } |
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[2434] | 137 | |
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| 138 | //ll |
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