libavcodec/acelp_vectors.c

   1 /*
   2  * adaptive and fixed codebook vector operations for ACELP-based codecs
   3  *
   4  * Copyright (c) 2008 Vladimir Voroshilov
   5  *
   6  * This file is part of FFmpeg.
   7  *
   8  * FFmpeg is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2.1 of the License, or (at your option) any later version.
  12  *
  13  * FFmpeg is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with FFmpeg; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  21  */
  22
  23 #include <inttypes.h>
  24 #include "avcodec.h"
  25 #include "acelp_vectors.h"
  26
  27 const uint8_t ff_fc_2pulses_9bits_track1[16] =
  28 {
  29     1,  3,
  30     6,  8,
  31     11, 13,
  32     16, 18,
  33     21, 23,
  34     26, 28,
  35     31, 33,
  36     36, 38
  37 };
  38 const uint8_t ff_fc_2pulses_9bits_track1_gray[16] =
  39 {
  40   1,  3,
  41   8,  6,
  42   18, 16,
  43   11, 13,
  44   38, 36,
  45   31, 33,
  46   21, 23,
  47   28, 26,
  48 };
  49
  50 const uint8_t ff_fc_2pulses_9bits_track2_gray[32] =
  51 {
  52   0,  2,
  53   5,  4,
  54   12, 10,
  55   7,  9,
  56   25, 24,
  57   20, 22,
  58   14, 15,
  59   19, 17,
  60   36, 31,
  61   21, 26,
  62   1,  6,
  63   16, 11,
  64   27, 29,
  65   32, 30,
  66   39, 37,
  67   34, 35,
  68 };
  69
  70 const uint8_t ff_fc_4pulses_8bits_tracks_13[16] =
  71 {
  72   0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75,
  73 };
  74
  75 const uint8_t ff_fc_4pulses_8bits_track_4[32] =
  76 {
  77     3,  4,
  78     8,  9,
  79     13, 14,
  80     18, 19,
  81     23, 24,
  82     28, 29,
  83     33, 34,
  84     38, 39,
  85     43, 44,
  86     48, 49,
  87     53, 54,
  88     58, 59,
  89     63, 64,
  90     68, 69,
  91     73, 74,
  92     78, 79,
  93 };
  94
  95 #if 0
  96 static uint8_t gray_decode[32] =
  97 {
  98     0,  1,  3,  2,  7,  6,  4,  5,
  99    15, 14, 12, 13,  8,  9, 11, 10,
 100    31, 30, 28, 29, 24, 25, 27, 26,
 101    16, 17, 19, 18, 23, 22, 20, 21
 102 };
 103 #endif
 104
 105 void ff_acelp_fc_pulse_per_track(
 106         int16_t* fc_v,
 107         const uint8_t *tab1,
 108         const uint8_t *tab2,
 109         int pulse_indexes,
 110         int pulse_signs,
 111         int pulse_count,
 112         int bits)
 113 {
 114     int mask = (1 << bits) - 1;
 115     int i;
 116
 117     for(i=0; i<pulse_count; i++)
 118     {
 119         fc_v[i + tab1[pulse_indexes & mask]] +=
 120                 (pulse_signs & 1) ? 8191 : -8192; // +/-1 in (2.13)
 121
 122         pulse_indexes >>= bits;
 123         pulse_signs >>= 1;
 124     }
 125
 126     fc_v[tab2[pulse_indexes]] += (pulse_signs & 1) ? 8191 : -8192;
 127 }
 128
 129 void ff_acelp_weighted_vector_sum(
 130         int16_t* out,
 131         const int16_t *in_a,
 132         const int16_t *in_b,
 133         int16_t weight_coeff_a,
 134         int16_t weight_coeff_b,
 135         int16_t rounder,
 136         int shift,
 137         int length)
 138 {
 139     int i;
 140
 141     // Clipping required here; breaks OVERFLOW test.
 142     for(i=0; i<length; i++)
 143         out[i] = av_clip_int16((
 144                  in_a[i] * weight_coeff_a +
 145                  in_b[i] * weight_coeff_b +
 146                  rounder) >> shift);
 147 }