FFmpeg/libavcodec/ac3tab.h

/**
 * @file ac3tab.h
 * tables taken directly from AC3 spec.
 */

/* possible frequencies */
static const uint16_t ac3_freqs[3] = { 48000, 44100, 32000 };

/* possible bitrates */
static const uint16_t ac3_bitratetab[19] = {
    32, 40, 48, 56, 64, 80, 96, 112, 128,
    160, 192, 224, 256, 320, 384, 448, 512, 576, 640
};

static uint8_t masktab[253];

static const uint8_t latab[260]= {
0x0040,0x003f,0x003e,0x003d,0x003c,0x003b,0x003a,0x0039,0x0038,0x0037,
0x0036,0x0035,0x0034,0x0034,0x0033,0x0032,0x0031,0x0030,0x002f,0x002f,
0x002e,0x002d,0x002c,0x002c,0x002b,0x002a,0x0029,0x0029,0x0028,0x0027,
0x0026,0x0026,0x0025,0x0024,0x0024,0x0023,0x0023,0x0022,0x0021,0x0021,
0x0020,0x0020,0x001f,0x001e,0x001e,0x001d,0x001d,0x001c,0x001c,0x001b,
0x001b,0x001a,0x001a,0x0019,0x0019,0x0018,0x0018,0x0017,0x0017,0x0016,
0x0016,0x0015,0x0015,0x0015,0x0014,0x0014,0x0013,0x0013,0x0013,0x0012,
0x0012,0x0012,0x0011,0x0011,0x0011,0x0010,0x0010,0x0010,0x000f,0x000f,
0x000f,0x000e,0x000e,0x000e,0x000d,0x000d,0x000d,0x000d,0x000c,0x000c,
0x000c,0x000c,0x000b,0x000b,0x000b,0x000b,0x000a,0x000a,0x000a,0x000a,
0x000a,0x0009,0x0009,0x0009,0x0009,0x0009,0x0008,0x0008,0x0008,0x0008,
0x0008,0x0008,0x0007,0x0007,0x0007,0x0007,0x0007,0x0007,0x0006,0x0006,
0x0006,0x0006,0x0006,0x0006,0x0006,0x0006,0x0005,0x0005,0x0005,0x0005,
0x0005,0x0005,0x0005,0x0005,0x0004,0x0004,0x0004,0x0004,0x0004,0x0004,
0x0004,0x0004,0x0004,0x0004,0x0004,0x0003,0x0003,0x0003,0x0003,0x0003,
0x0003,0x0003,0x0003,0x0003,0x0003,0x0003,0x0003,0x0003,0x0003,0x0002,
0x0002,0x0002,0x0002,0x0002,0x0002,0x0002,0x0002,0x0002,0x0002,0x0002,
0x0002,0x0002,0x0002,0x0002,0x0002,0x0002,0x0002,0x0002,0x0001,0x0001,
0x0001,0x0001,0x0001,0x0001,0x0001,0x0001,0x0001,0x0001,0x0001,0x0001,
0x0001,0x0001,0x0001,0x0001,0x0001,0x0001,0x0001,0x0001,0x0001,0x0001,
0x0001,0x0001,0x0001,0x0001,0x0001,0x0001,0x0001,0x0001,0x0001,0x0001,
0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,
0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,
0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,
0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,
0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,
};

static const uint16_t hth[50][3]= {
{ 0x04d0,0x04f0,0x0580 },
{ 0x04d0,0x04f0,0x0580 },
{ 0x0440,0x0460,0x04b0 },
{ 0x0400,0x0410,0x0450 },
{ 0x03e0,0x03e0,0x0420 },
{ 0x03c0,0x03d0,0x03f0 },
{ 0x03b0,0x03c0,0x03e0 },
{ 0x03b0,0x03b0,0x03d0 },
{ 0x03a0,0x03b0,0x03c0 },
{ 0x03a0,0x03a0,0x03b0 },
{ 0x03a0,0x03a0,0x03b0 },
{ 0x03a0,0x03a0,0x03b0 },
{ 0x03a0,0x03a0,0x03a0 },
{ 0x0390,0x03a0,0x03a0 },
{ 0x0390,0x0390,0x03a0 },
{ 0x0390,0x0390,0x03a0 },
{ 0x0380,0x0390,0x03a0 },
{ 0x0380,0x0380,0x03a0 },
{ 0x0370,0x0380,0x03a0 },
{ 0x0370,0x0380,0x03a0 },
{ 0x0360,0x0370,0x0390 },
{ 0x0360,0x0370,0x0390 },
{ 0x0350,0x0360,0x0390 },
{ 0x0350,0x0360,0x0390 },
{ 0x0340,0x0350,0x0380 },
{ 0x0340,0x0350,0x0380 },
{ 0x0330,0x0340,0x0380 },
{ 0x0320,0x0340,0x0370 },
{ 0x0310,0x0320,0x0360 },
{ 0x0300,0x0310,0x0350 },
{ 0x02f0,0x0300,0x0340 },
{ 0x02f0,0x02f0,0x0330 },
{ 0x02f0,0x02f0,0x0320 },
{ 0x02f0,0x02f0,0x0310 },
{ 0x0300,0x02f0,0x0300 },
{ 0x0310,0x0300,0x02f0 },
{ 0x0340,0x0320,0x02f0 },
{ 0x0390,0x0350,0x02f0 },
{ 0x03e0,0x0390,0x0300 },
{ 0x0420,0x03e0,0x0310 },
{ 0x0460,0x0420,0x0330 },
{ 0x0490,0x0450,0x0350 },
{ 0x04a0,0x04a0,0x03c0 },
{ 0x0460,0x0490,0x0410 },
{ 0x0440,0x0460,0x0470 },
{ 0x0440,0x0440,0x04a0 },
{ 0x0520,0x0480,0x0460 },
{ 0x0800,0x0630,0x0440 },
{ 0x0840,0x0840,0x0450 },
{ 0x0840,0x0840,0x04e0 },
};

static const uint8_t baptab[64]= {
    0, 1, 1, 1, 1, 1, 2, 2, 3, 3,
    3, 4, 4, 5, 5, 6, 6, 6, 6, 7,
    7, 7, 7, 8, 8, 8, 8, 9, 9, 9,
    9, 10, 10, 10, 10, 11, 11, 11, 11, 12,
    12, 12, 12, 13, 13, 13, 13, 14, 14, 14,
    14, 14, 14, 14, 14, 15, 15, 15, 15, 15,
    15, 15, 15, 15,
};

static const uint8_t sdecaytab[4]={
    0x0f, 0x11, 0x13, 0x15,
};

static const uint8_t fdecaytab[4]={
    0x3f, 0x53, 0x67, 0x7b,
};

static const uint16_t sgaintab[4]= {
    0x540, 0x4d8, 0x478, 0x410,
};

static const uint16_t dbkneetab[4]= {
    0x000, 0x700, 0x900, 0xb00,
};

static const uint16_t floortab[8]= {
    0x2f0, 0x2b0, 0x270, 0x230, 0x1f0, 0x170, 0x0f0, 0xf800,
};

static const uint16_t fgaintab[8]= {
    0x080, 0x100, 0x180, 0x200, 0x280, 0x300, 0x380, 0x400,
};

static const uint8_t bndsz[50]={
    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 3, 3, 3, 3, 3,
    3, 6, 6, 6, 6, 6, 6, 12, 12, 12, 12, 24, 24, 24, 24, 24
};

static uint8_t bndtab[51];

/* AC3 MDCT window */
static int16_t ac3_window[256];

/* fft & mdct sin cos tables */
static int16_t costab[64];
static int16_t sintab[64];
static int16_t fft_rev[512];
static int16_t xcos1[128];
static int16_t xsin1[128];