From 4a53b83691ac1c1feefe8749756b149c31ad4ccb Mon Sep 17 00:00:00 2001 From: foo86 Date: Fri, 8 Jan 2016 00:48:57 +0300 Subject: avcodec/dca: add math helpers and fixed point DCT --- libavcodec/dcadct.c | 362 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 362 insertions(+) create mode 100644 libavcodec/dcadct.c (limited to 'libavcodec/dcadct.c') diff --git a/libavcodec/dcadct.c b/libavcodec/dcadct.c new file mode 100644 index 0000000000..1082aa884d --- /dev/null +++ b/libavcodec/dcadct.c @@ -0,0 +1,362 @@ +/* + * Copyright (C) 2016 foo86 + * + * 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 + */ + +#include "libavutil/common.h" + +#include "dcadct.h" +#include "dcamath.h" + +static void sum_a(const int *input, int *output, int len) +{ + int i; + + for (i = 0; i < len; i++) + output[i] = input[2 * i] + input[2 * i + 1]; +} + +static void sum_b(const int *input, int *output, int len) +{ + int i; + + output[0] = input[0]; + for (i = 1; i < len; i++) + output[i] = input[2 * i] + input[2 * i - 1]; +} + +static void sum_c(const int *input, int *output, int len) +{ + int i; + + for (i = 0; i < len; i++) + output[i] = input[2 * i]; +} + +static void sum_d(const int *input, int *output, int len) +{ + int i; + + output[0] = input[1]; + for (i = 1; i < len; i++) + output[i] = input[2 * i - 1] + input[2 * i + 1]; +} + +static void dct_a(const int *input, int *output) +{ + static const int cos_mod[8][8] = { + { 8348215, 8027397, 7398092, 6484482, 5321677, 3954362, 2435084, 822227 }, + { 8027397, 5321677, 822227, -3954362, -7398092, -8348215, -6484482, -2435084 }, + { 7398092, 822227, -6484482, -8027397, -2435084, 5321677, 8348215, 3954362 }, + { 6484482, -3954362, -8027397, 822227, 8348215, 2435084, -7398092, -5321677 }, + { 5321677, -7398092, -2435084, 8348215, -822227, -8027397, 3954362, 6484482 }, + { 3954362, -8348215, 5321677, 2435084, -8027397, 6484482, 822227, -7398092 }, + { 2435084, -6484482, 8348215, -7398092, 3954362, 822227, -5321677, 8027397 }, + { 822227, -2435084, 3954362, -5321677, 6484482, -7398092, 8027397, -8348215 } + }; + + int i, j; + + for (i = 0; i < 8; i++) { + int64_t res = 0; + for (j = 0; j < 8; j++) + res += (int64_t)cos_mod[i][j] * input[j]; + output[i] = norm23(res); + } +} + +static void dct_b(const int *input, int *output) +{ + static const int cos_mod[8][7] = { + { 8227423, 7750063, 6974873, 5931642, 4660461, 3210181, 1636536 }, + { 6974873, 3210181, -1636536, -5931642, -8227423, -7750063, -4660461 }, + { 4660461, -3210181, -8227423, -5931642, 1636536, 7750063, 6974873 }, + { 1636536, -7750063, -4660461, 5931642, 6974873, -3210181, -8227423 }, + { -1636536, -7750063, 4660461, 5931642, -6974873, -3210181, 8227423 }, + { -4660461, -3210181, 8227423, -5931642, -1636536, 7750063, -6974873 }, + { -6974873, 3210181, 1636536, -5931642, 8227423, -7750063, 4660461 }, + { -8227423, 7750063, -6974873, 5931642, -4660461, 3210181, -1636536 } + }; + + int i, j; + + for (i = 0; i < 8; i++) { + int64_t res = input[0] * (INT64_C(1) << 23); + for (j = 0; j < 7; j++) + res += (int64_t)cos_mod[i][j] * input[1 + j]; + output[i] = norm23(res); + } +} + +static void mod_a(const int *input, int *output) +{ + static const int cos_mod[16] = { + 4199362, 4240198, 4323885, 4454708, + 4639772, 4890013, 5221943, 5660703, + -6245623, -7040975, -8158494, -9809974, + -12450076, -17261920, -28585092, -85479984 + }; + + int i, k; + + for (i = 0; i < 8; i++) + output[i] = mul23(cos_mod[i], input[i] + input[8 + i]); + + for (i = 8, k = 7; i < 16; i++, k--) + output[i] = mul23(cos_mod[i], input[k] - input[8 + k]); +} + +static void mod_b(int *input, int *output) +{ + static const int cos_mod[8] = { + 4214598, 4383036, 4755871, 5425934, + 6611520, 8897610, 14448934, 42791536 + }; + + int i, k; + + for (i = 0; i < 8; i++) + input[8 + i] = mul23(cos_mod[i], input[8 + i]); + + for (i = 0; i < 8; i++) + output[i] = input[i] + input[8 + i]; + + for (i = 8, k = 7; i < 16; i++, k--) + output[i] = input[k] - input[8 + k]; +} + +static void mod_c(const int *input, int *output) +{ + static const int cos_mod[32] = { + 1048892, 1051425, 1056522, 1064244, + 1074689, 1087987, 1104313, 1123884, + 1146975, 1173922, 1205139, 1241133, + 1282529, 1330095, 1384791, 1447815, + -1520688, -1605358, -1704360, -1821051, + -1959964, -2127368, -2332183, -2587535, + -2913561, -3342802, -3931480, -4785806, + -6133390, -8566050, -14253820, -42727120 + }; + + int i, k; + + for (i = 0; i < 16; i++) + output[i] = mul23(cos_mod[i], input[i] + input[16 + i]); + + for (i = 16, k = 15; i < 32; i++, k--) + output[i] = mul23(cos_mod[i], input[k] - input[16 + k]); +} + +static void clp_v(int *input, int len) +{ + int i; + + for (i = 0; i < len; i++) + input[i] = clip23(input[i]); +} + +static void imdct_half_32(int32_t *output, const int32_t *input) +{ + int buf_a[32], buf_b[32]; + int i, k, mag, shift, round; + + mag = 0; + for (i = 0; i < 32; i++) + mag += abs(input[i]); + + shift = mag > 0x400000 ? 2 : 0; + round = shift > 0 ? 1 << (shift - 1) : 0; + + for (i = 0; i < 32; i++) + buf_a[i] = (input[i] + round) >> shift; + + sum_a(buf_a, buf_b + 0, 16); + sum_b(buf_a, buf_b + 16, 16); + clp_v(buf_b, 32); + + sum_a(buf_b + 0, buf_a + 0, 8); + sum_b(buf_b + 0, buf_a + 8, 8); + sum_c(buf_b + 16, buf_a + 16, 8); + sum_d(buf_b + 16, buf_a + 24, 8); + clp_v(buf_a, 32); + + dct_a(buf_a + 0, buf_b + 0); + dct_b(buf_a + 8, buf_b + 8); + dct_b(buf_a + 16, buf_b + 16); + dct_b(buf_a + 24, buf_b + 24); + clp_v(buf_b, 32); + + mod_a(buf_b + 0, buf_a + 0); + mod_b(buf_b + 16, buf_a + 16); + clp_v(buf_a, 32); + + mod_c(buf_a, buf_b); + + for (i = 0; i < 32; i++) + buf_b[i] = clip23(buf_b[i] * (1 << shift)); + + for (i = 0, k = 31; i < 16; i++, k--) { + output[ i] = clip23(buf_b[i] - buf_b[k]); + output[16 + i] = clip23(buf_b[i] + buf_b[k]); + } +} + +static void mod64_a(const int *input, int *output) +{ + static const int cos_mod[32] = { + 4195568, 4205700, 4226086, 4256977, + 4298755, 4351949, 4417251, 4495537, + 4587901, 4695690, 4820557, 4964534, + 5130115, 5320382, 5539164, 5791261, + -6082752, -6421430, -6817439, -7284203, + -7839855, -8509474, -9328732, -10350140, + -11654242, -13371208, -15725922, -19143224, + -24533560, -34264200, -57015280, -170908480 + }; + + int i, k; + + for (i = 0; i < 16; i++) + output[i] = mul23(cos_mod[i], input[i] + input[16 + i]); + + for (i = 16, k = 15; i < 32; i++, k--) + output[i] = mul23(cos_mod[i], input[k] - input[16 + k]); +} + +static void mod64_b(int *input, int *output) +{ + static const int cos_mod[16] = { + 4199362, 4240198, 4323885, 4454708, + 4639772, 4890013, 5221943, 5660703, + 6245623, 7040975, 8158494, 9809974, + 12450076, 17261920, 28585092, 85479984 + }; + + int i, k; + + for (i = 0; i < 16; i++) + input[16 + i] = mul23(cos_mod[i], input[16 + i]); + + for (i = 0; i < 16; i++) + output[i] = input[i] + input[16 + i]; + + for (i = 16, k = 15; i < 32; i++, k--) + output[i] = input[k] - input[16 + k]; +} + +static void mod64_c(const int *input, int *output) +{ + static const int cos_mod[64] = { + 741511, 741958, 742853, 744199, + 746001, 748262, 750992, 754197, + 757888, 762077, 766777, 772003, + 777772, 784105, 791021, 798546, + 806707, 815532, 825054, 835311, + 846342, 858193, 870912, 884554, + 899181, 914860, 931667, 949686, + 969011, 989747, 1012012, 1035941, + -1061684, -1089412, -1119320, -1151629, + -1186595, -1224511, -1265719, -1310613, + -1359657, -1413400, -1472490, -1537703, + -1609974, -1690442, -1780506, -1881904, + -1996824, -2128058, -2279225, -2455101, + -2662128, -2909200, -3208956, -3579983, + -4050785, -4667404, -5509372, -6726913, + -8641940, -12091426, -20144284, -60420720 + }; + + int i, k; + + for (i = 0; i < 32; i++) + output[i] = mul23(cos_mod[i], input[i] + input[32 + i]); + + for (i = 32, k = 31; i < 64; i++, k--) + output[i] = mul23(cos_mod[i], input[k] - input[32 + k]); +} + +static void imdct_half_64(int32_t *output, const int32_t *input) +{ + int buf_a[64], buf_b[64]; + int i, k, mag, shift, round; + + mag = 0; + for (i = 0; i < 64; i++) + mag += abs(input[i]); + + shift = mag > 0x400000 ? 2 : 0; + round = shift > 0 ? 1 << (shift - 1) : 0; + + for (i = 0; i < 64; i++) + buf_a[i] = (input[i] + round) >> shift; + + sum_a(buf_a, buf_b + 0, 32); + sum_b(buf_a, buf_b + 32, 32); + clp_v(buf_b, 64); + + sum_a(buf_b + 0, buf_a + 0, 16); + sum_b(buf_b + 0, buf_a + 16, 16); + sum_c(buf_b + 32, buf_a + 32, 16); + sum_d(buf_b + 32, buf_a + 48, 16); + clp_v(buf_a, 64); + + sum_a(buf_a + 0, buf_b + 0, 8); + sum_b(buf_a + 0, buf_b + 8, 8); + sum_c(buf_a + 16, buf_b + 16, 8); + sum_d(buf_a + 16, buf_b + 24, 8); + sum_c(buf_a + 32, buf_b + 32, 8); + sum_d(buf_a + 32, buf_b + 40, 8); + sum_c(buf_a + 48, buf_b + 48, 8); + sum_d(buf_a + 48, buf_b + 56, 8); + clp_v(buf_b, 64); + + dct_a(buf_b + 0, buf_a + 0); + dct_b(buf_b + 8, buf_a + 8); + dct_b(buf_b + 16, buf_a + 16); + dct_b(buf_b + 24, buf_a + 24); + dct_b(buf_b + 32, buf_a + 32); + dct_b(buf_b + 40, buf_a + 40); + dct_b(buf_b + 48, buf_a + 48); + dct_b(buf_b + 56, buf_a + 56); + clp_v(buf_a, 64); + + mod_a(buf_a + 0, buf_b + 0); + mod_b(buf_a + 16, buf_b + 16); + mod_b(buf_a + 32, buf_b + 32); + mod_b(buf_a + 48, buf_b + 48); + clp_v(buf_b, 64); + + mod64_a(buf_b + 0, buf_a + 0); + mod64_b(buf_b + 32, buf_a + 32); + clp_v(buf_a, 64); + + mod64_c(buf_a, buf_b); + + for (i = 0; i < 64; i++) + buf_b[i] = clip23(buf_b[i] * (1 << shift)); + + for (i = 0, k = 63; i < 32; i++, k--) { + output[ i] = clip23(buf_b[i] - buf_b[k]); + output[32 + i] = clip23(buf_b[i] + buf_b[k]); + } +} + +av_cold void ff_dcadct_init(DCADCTContext *c) +{ + c->imdct_half[0] = imdct_half_32; + c->imdct_half[1] = imdct_half_64; +} -- cgit v1.2.3