text: /*
   * Copyright (c) 2001-2003 The ffmpeg Project
   *
   * This file is part of FFmpeg.
   *
   * FFmpeg is free software; you can redistribute it and/or
   * modify it under the terms of the GNU Lesser General Public
   * License as published by the Free Software Foundation; either
   * version 2.1 of the License, or (at your option) any later version.
   *
   * FFmpeg 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
   * Lesser General Public License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with FFmpeg; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
   */
  
  /**
   * @file
   * ADPCM tables
   */
  
  #include <stdint.h>
  
  /* ff_adpcm_step_table[] and ff_adpcm_index_table[] are from the ADPCM
     reference source */
  /* This is the index table: */
  const int8_t ff_adpcm_index_table[16] = {
      -1, -1, -1, -1, 2, 4, 6, 8,
      -1, -1, -1, -1, 2, 4, 6, 8,
  };
  
  /**
   * This is the step table. Note that many programs use slight deviations from
   * this table, but such deviations are negligible:
   */
  const int16_t ff_adpcm_step_table[89] = {
          7,     8,     9,    10,    11,    12,    13,    14,    16,    17,
         19,    21,    23,    25,    28,    31,    34,    37,    41,    45,
         50,    55,    60,    66,    73,    80,    88,    97,   107,   118,
        130,   143,   157,   173,   190,   209,   230,   253,   279,   307,
        337,   371,   408,   449,   494,   544,   598,   658,   724,   796,
        876,   963,  1060,  1166,  1282,  1411,  1552,  1707,  1878,  2066,
       2272,  2499,  2749,  3024,  3327,  3660,  4026,  4428,  4871,  5358,
       5894,  6484,  7132,  7845,  8630,  9493, 10442, 11487, 12635, 13899,
      15289, 16818, 18500, 20350, 22385, 24623, 27086, 29794, 32767
  };
  
  const int16_t ff_adpcm_oki_step_table[49] = {
       16,  17,  19,  21,   23,   25,   28,   31,   34,  37,
       41,  45,  50,  55,   60,   66,   73,   80,   88,  97,
      107, 118, 130, 143,  157,  173,  190,  209,  230, 253,
      279, 307, 337, 371,  408,  449,  494,  544,  598, 658,
      724, 796, 876, 963, 1060, 1166, 1282, 1411, 1552
  };
  
  /* These are for MS-ADPCM */
  /* ff_adpcm_AdaptationTable[], ff_adpcm_AdaptCoeff1[], and
     ff_adpcm_AdaptCoeff2[] are from libsndfile */
  const int16_t ff_adpcm_AdaptationTable[] = {
      230, 230, 230, 230, 307, 409, 512, 614,
      768, 614, 512, 409, 307, 230, 230, 230
  };
  
  /** Divided by 4 to fit in 8-bit integers */
  const uint8_t ff_adpcm_AdaptCoeff1[] = {
      64, 128, 0, 48, 60, 115, 98
  };
  
  /** Divided by 4 to fit in 8-bit integers */
  const int8_t ff_adpcm_AdaptCoeff2[] = {
      0, -64, 0, 16, 0, -52, -58
  };
  
  const int16_t ff_adpcm_yamaha_indexscale[] = {
      230, 230, 230, 230, 307, 409, 512, 614,
      230, 230, 230, 230, 307, 409, 512, 614
  };
  
  const int8_t ff_adpcm_yamaha_difflookup[] = {
       1,  3,  5,  7,  9,  11,  13,  15,
      -1, -3, -5, -7, -9, -11, -13, -15
  };
  
  const int16_t ff_adpcm_afc_coeffs[2][16] = {
      { 0, 2048, 0, 1024, 4096, 3584, 3072, 4608, 4200, 4800, 5120, 2048, 1024, 64512, 64512, 63488 },
      { 0, 0, 2048, 1024, 63488, 64000, 64512, 62976, 63288, 63236, 62464, 63488, 64512, 1024, 0, 0 }
  };
  