Ryujinx/src/Ryujinx.Graphics.Nvdec.Vp9/QuantCommon.cs

using System;
using System.Diagnostics;

namespace Ryujinx.Graphics.Nvdec.Vp9
{
    internal static class QuantCommon
    {
        public const int MaxQ = 255;
        public const int QindexBits = 8;

        private static readonly short[] _dcQlookup =
        [
            4, 8, 8, 9, 10, 11, 12, 12, 13, 14, 15, 16, 17, 18, 19, 19, 20, 21, 22, 23, 24, 25, 26, 26, 27, 28, 29,
            30, 31, 32, 32, 33, 34, 35, 36, 37, 38, 38, 39, 40, 41, 42, 43, 43, 44, 45, 46, 47, 48, 48, 49, 50, 51,
            52, 53, 53, 54, 55, 56, 57, 57, 58, 59, 60, 61, 62, 62, 63, 64, 65, 66, 66, 67, 68, 69, 70, 70, 71, 72,
            73, 74, 74, 75, 76, 77, 78, 78, 79, 80, 81, 81, 82, 83, 84, 85, 85, 87, 88, 90, 92, 93, 95, 96, 98, 99,
            101, 102, 104, 105, 107, 108, 110, 111, 113, 114, 116, 117, 118, 120, 121, 123, 125, 127, 129, 131, 134,
            136, 138, 140, 142, 144, 146, 148, 150, 152, 154, 156, 158, 161, 164, 166, 169, 172, 174, 177, 180, 182,
            185, 187, 190, 192, 195, 199, 202, 205, 208, 211, 214, 217, 220, 223, 226, 230, 233, 237, 240, 243, 247,
            250, 253, 257, 261, 265, 269, 272, 276, 280, 284, 288, 292, 296, 300, 304, 309, 313, 317, 322, 326, 330,
            335, 340, 344, 349, 354, 359, 364, 369, 374, 379, 384, 389, 395, 400, 406, 411, 417, 423, 429, 435, 441,
            447, 454, 461, 467, 475, 482, 489, 497, 505, 513, 522, 530, 539, 549, 559, 569, 579, 590, 602, 614, 626,
            640, 654, 668, 684, 700, 717, 736, 755, 775, 796, 819, 843, 869, 896, 925, 955, 988, 1022, 1058, 1098,
            1139, 1184, 1232, 1282, 1336
        ];

        private static readonly short[] _dcQlookup10 =
        [
            4, 9, 10, 13, 15, 17, 20, 22, 25, 28, 31, 34, 37, 40, 43, 47, 50, 53, 57, 60, 64, 68, 71, 75, 78, 82,
            86, 90, 93, 97, 101, 105, 109, 113, 116, 120, 124, 128, 132, 136, 140, 143, 147, 151, 155, 159, 163,
            166, 170, 174, 178, 182, 185, 189, 193, 197, 200, 204, 208, 212, 215, 219, 223, 226, 230, 233, 237, 241,
            244, 248, 251, 255, 259, 262, 266, 269, 273, 276, 280, 283, 287, 290, 293, 297, 300, 304, 307, 310, 314,
            317, 321, 324, 327, 331, 334, 337, 343, 350, 356, 362, 369, 375, 381, 387, 394, 400, 406, 412, 418, 424,
            430, 436, 442, 448, 454, 460, 466, 472, 478, 484, 490, 499, 507, 516, 525, 533, 542, 550, 559, 567, 576,
            584, 592, 601, 609, 617, 625, 634, 644, 655, 666, 676, 687, 698, 708, 718, 729, 739, 749, 759, 770, 782,
            795, 807, 819, 831, 844, 856, 868, 880, 891, 906, 920, 933, 947, 961, 975, 988, 1001, 1015, 1030, 1045,
            1061, 1076, 1090, 1105, 1120, 1137, 1153, 1170, 1186, 1202, 1218, 1236, 1253, 1271, 1288, 1306, 1323,
            1342, 1361, 1379, 1398, 1416, 1436, 1456, 1476, 1496, 1516, 1537, 1559, 1580, 1601, 1624, 1647, 1670,
            1692, 1717, 1741, 1766, 1791, 1817, 1844, 1871, 1900, 1929, 1958, 1990, 2021, 2054, 2088, 2123, 2159,
            2197, 2236, 2276, 2319, 2363, 2410, 2458, 2508, 2561, 2616, 2675, 2737, 2802, 2871, 2944, 3020, 3102,
            3188, 3280, 3375, 3478, 3586, 3702, 3823, 3953, 4089, 4236, 4394, 4559, 4737, 4929, 5130, 5347
        ];

        private static readonly short[] _dcQlookup12 =
        [
            4, 12, 18, 25, 33, 41, 50, 60, 70, 80, 91, 103, 115, 127, 140, 153, 166, 180, 194, 208, 222, 237, 251,
            266, 281, 296, 312, 327, 343, 358, 374, 390, 405, 421, 437, 453, 469, 484, 500, 516, 532, 548, 564, 580,
            596, 611, 627, 643, 659, 674, 690, 706, 721, 737, 752, 768, 783, 798, 814, 829, 844, 859, 874, 889, 904,
            919, 934, 949, 964, 978, 993, 1008, 1022, 1037, 1051, 1065, 1080, 1094, 1108, 1122, 1136, 1151, 1165,
            1179, 1192, 1206, 1220, 1234, 1248, 1261, 1275, 1288, 1302, 1315, 1329, 1342, 1368, 1393, 1419, 1444,
            1469, 1494, 1519, 1544, 1569, 1594, 1618, 1643, 1668, 1692, 1717, 1741, 1765, 1789, 1814, 1838, 1862,
            1885, 1909, 1933, 1957, 1992, 2027, 2061, 2096, 2130, 2165, 2199, 2233, 2267, 2300, 2334, 2367, 2400,
            2434, 2467, 2499, 2532, 2575, 2618, 2661, 2704, 2746, 2788, 2830, 2872, 2913, 2954, 2995, 3036, 3076,
            3127, 3177, 3226, 3275, 3324, 3373, 3421, 3469, 3517, 3565, 3621, 3677, 3733, 3788, 3843, 3897, 3951,
            4005, 4058, 4119, 4181, 4241, 4301, 4361, 4420, 4479, 4546, 4612, 4677, 4742, 4807, 4871, 4942, 5013,
            5083, 5153, 5222, 5291, 5367, 5442, 5517, 5591, 5665, 5745, 5825, 5905, 5984, 6063, 6149, 6234, 6319,
            6404, 6495, 6587, 6678, 6769, 6867, 6966, 7064, 7163, 7269, 7376, 7483, 7599, 7715, 7832, 7958, 8085,
            8214, 8352, 8492, 8635, 8788, 8945, 9104, 9275, 9450, 9639, 9832, 10031, 10245, 10465, 10702, 10946,
            11210, 11482, 11776, 12081, 12409, 12750, 13118, 13501, 13913, 14343, 14807, 15290, 15812, 16356, 16943,
            17575, 18237, 18949, 19718, 20521, 21387
        ];

        private static readonly short[] _acQlookup =
        [
            4, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,
            34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59,
            60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85,
            86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 104, 106, 108, 110, 112, 114,
            116, 118, 120, 122, 124, 126, 128, 130, 132, 134, 136, 138, 140, 142, 144, 146, 148, 150, 152, 155, 158,
            161, 164, 167, 170, 173, 176, 179, 182, 185, 188, 191, 194, 197, 200, 203, 207, 211, 215, 219, 223, 227,
            231, 235, 239, 243, 247, 251, 255, 260, 265, 270, 275, 280, 285, 290, 295, 300, 305, 311, 317, 323, 329,
            335, 341, 347, 353, 359, 366, 373, 380, 387, 394, 401, 408, 416, 424, 432, 440, 448, 456, 465, 474, 483,
            492, 501, 510, 520, 530, 540, 550, 560, 571, 582, 593, 604, 615, 627, 639, 651, 663, 676, 689, 702, 715,
            729, 743, 757, 771, 786, 801, 816, 832, 848, 864, 881, 898, 915, 933, 951, 969, 988, 1007, 1026, 1046,
            1066, 1087, 1108, 1129, 1151, 1173, 1196, 1219, 1243, 1267, 1292, 1317, 1343, 1369, 1396, 1423, 1451,
            1479, 1508, 1537, 1567, 1597, 1628, 1660, 1692, 1725, 1759, 1793, 1828
        ];

        private static readonly short[] _acQlookup10 =
        [
            4, 9, 11, 13, 16, 18, 21, 24, 27, 30, 33, 37, 40, 44, 48, 51, 55, 59, 63, 67, 71, 75, 79, 83, 88, 92,
            96, 100, 105, 109, 114, 118, 122, 127, 131, 136, 140, 145, 149, 154, 158, 163, 168, 172, 177, 181, 186,
            190, 195, 199, 204, 208, 213, 217, 222, 226, 231, 235, 240, 244, 249, 253, 258, 262, 267, 271, 275, 280,
            284, 289, 293, 297, 302, 306, 311, 315, 319, 324, 328, 332, 337, 341, 345, 349, 354, 358, 362, 367, 371,
            375, 379, 384, 388, 392, 396, 401, 409, 417, 425, 433, 441, 449, 458, 466, 474, 482, 490, 498, 506, 514,
            523, 531, 539, 547, 555, 563, 571, 579, 588, 596, 604, 616, 628, 640, 652, 664, 676, 688, 700, 713, 725,
            737, 749, 761, 773, 785, 797, 809, 825, 841, 857, 873, 889, 905, 922, 938, 954, 970, 986, 1002, 1018,
            1038, 1058, 1078, 1098, 1118, 1138, 1158, 1178, 1198, 1218, 1242, 1266, 1290, 1314, 1338, 1362, 1386,
            1411, 1435, 1463, 1491, 1519, 1547, 1575, 1603, 1631, 1663, 1695, 1727, 1759, 1791, 1823, 1859, 1895,
            1931, 1967, 2003, 2039, 2079, 2119, 2159, 2199, 2239, 2283, 2327, 2371, 2415, 2459, 2507, 2555, 2603,
            2651, 2703, 2755, 2807, 2859, 2915, 2971, 3027, 3083, 3143, 3203, 3263, 3327, 3391, 3455, 3523, 3591,
            3659, 3731, 3803, 3876, 3952, 4028, 4104, 4184, 4264, 4348, 4432, 4516, 4604, 4692, 4784, 4876, 4972,
            5068, 5168, 5268, 5372, 5476, 5584, 5692, 5804, 5916, 6032, 6148, 6268, 6388, 6512, 6640, 6768, 6900,
            7036, 7172, 7312
        ];

        private static readonly short[] _acQlookup12 =
        [
            4, 13, 19, 27, 35, 44, 54, 64, 75, 87, 99, 112, 126, 139, 154, 168, 183, 199, 214, 230, 247, 263, 280,
            297, 314, 331, 349, 366, 384, 402, 420, 438, 456, 475, 493, 511, 530, 548, 567, 586, 604, 623, 642, 660,
            679, 698, 716, 735, 753, 772, 791, 809, 828, 846, 865, 884, 902, 920, 939, 957, 976, 994, 1012, 1030,
            1049, 1067, 1085, 1103, 1121, 1139, 1157, 1175, 1193, 1211, 1229, 1246, 1264, 1282, 1299, 1317, 1335,
            1352, 1370, 1387, 1405, 1422, 1440, 1457, 1474, 1491, 1509, 1526, 1543, 1560, 1577, 1595, 1627, 1660,
            1693, 1725, 1758, 1791, 1824, 1856, 1889, 1922, 1954, 1987, 2020, 2052, 2085, 2118, 2150, 2183, 2216,
            2248, 2281, 2313, 2346, 2378, 2411, 2459, 2508, 2556, 2605, 2653, 2701, 2750, 2798, 2847, 2895, 2943,
            2992, 3040, 3088, 3137, 3185, 3234, 3298, 3362, 3426, 3491, 3555, 3619, 3684, 3748, 3812, 3876, 3941,
            4005, 4069, 4149, 4230, 4310, 4390, 4470, 4550, 4631, 4711, 4791, 4871, 4967, 5064, 5160, 5256, 5352,
            5448, 5544, 5641, 5737, 5849, 5961, 6073, 6185, 6297, 6410, 6522, 6650, 6778, 6906, 7034, 7162, 7290,
            7435, 7579, 7723, 7867, 8011, 8155, 8315, 8475, 8635, 8795, 8956, 9132, 9308, 9484, 9660, 9836, 10028,
            10220, 10412, 10604, 10812, 11020, 11228, 11437, 11661, 11885, 12109, 12333, 12573, 12813, 13053, 13309,
            13565, 13821, 14093, 14365, 14637, 14925, 15213, 15502, 15806, 16110, 16414, 16734, 17054, 17390, 17726,
            18062, 18414, 18766, 19134, 19502, 19886, 20270, 20670, 21070, 21486, 21902, 22334, 22766, 23214, 23662,
            24126, 24590, 25070, 25551, 26047, 26559, 27071, 27599, 28143, 28687, 29247
        ];

        public static short DcQuant(int qindex, int delta, BitDepth bitDepth)
        {
            switch (bitDepth)
            {
                case BitDepth.Bits8: return _dcQlookup[Math.Clamp(qindex + delta, 0, MaxQ)];
                case BitDepth.Bits10: return _dcQlookup10[Math.Clamp(qindex + delta, 0, MaxQ)];
                case BitDepth.Bits12: return _dcQlookup12[Math.Clamp(qindex + delta, 0, MaxQ)];
                default:
                    Debug.Assert(false, "bitDepth should be Bits8, Bits10 or Bits12");
                    return -1;
            }
        }

        public static short AcQuant(int qindex, int delta, BitDepth bitDepth)
        {
            switch (bitDepth)
            {
                case BitDepth.Bits8: return _acQlookup[Math.Clamp(qindex + delta, 0, MaxQ)];
                case BitDepth.Bits10: return _acQlookup10[Math.Clamp(qindex + delta, 0, MaxQ)];
                case BitDepth.Bits12: return _acQlookup12[Math.Clamp(qindex + delta, 0, MaxQ)];
                default:
                    Debug.Assert(false, "bitDepth should be Bits8, Bits10 or Bits12");
                    return -1;
            }
        }
    }
}